Create a top-level "third_party" directory

This directory now contains third_party software that is vendored into
the Servo source tree. The idea is that it would eventually hold
webrender and other crates from mozilla-central as well with a standard
patch management approach for each.

75 files changed, 0 insertions, 11670 deletions

diff --git a/components/script/dom/bindings/codegen/parser/tests/test_any_null.py b/components/script/dom/bindings/codegen/parser/tests/test_any_null.py
deleted file mode 100644
index f9afdacb02f..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_any_null.py
+++ /dev/null
@@ -1,16 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DoubleNull {
-              attribute any? foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_argument_identifier_conflicts.py b/components/script/dom/bindings/codegen/parser/tests/test_argument_identifier_conflicts.py
deleted file mode 100644
index 3f50cb05158..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_argument_identifier_conflicts.py
+++ /dev/null
@@ -1,16 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface ArgumentIdentifierConflict {
-              undefined foo(boolean arg1, boolean arg1);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_argument_keywords.py b/components/script/dom/bindings/codegen/parser/tests/test_argument_keywords.py
deleted file mode 100644
index bbed33df926..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_argument_keywords.py
+++ /dev/null
@@ -1,22 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-    interface Foo {
-      undefined foo(object constructor);
-    };
-    """
-    )
-
-    results = parser.finish()
-    harness.check(len(results), 1, "Should have an interface")
-    iface = results[0]
-    harness.check(len(iface.members), 1, "Should have an operation")
-    operation = iface.members[0]
-    harness.check(len(operation.signatures()), 1, "Should have one signature")
-    (retval, args) = operation.signatures()[0]
-    harness.check(len(args), 1, "Should have an argument")
-    harness.check(
-        args[0].identifier.name,
-        "constructor",
-        "Should have an identifier named 'constructor'",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_arraybuffer.py b/components/script/dom/bindings/codegen/parser/tests/test_arraybuffer.py
deleted file mode 100644
index b762d06ac29..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_arraybuffer.py
+++ /dev/null
@@ -1,95 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestArrayBuffer {
-          attribute ArrayBuffer bufferAttr;
-          undefined bufferMethod(ArrayBuffer arg1, ArrayBuffer? arg2, sequence<ArrayBuffer> arg3);
-
-          attribute ArrayBufferView viewAttr;
-          undefined viewMethod(ArrayBufferView arg1, ArrayBufferView? arg2, sequence<ArrayBufferView> arg3);
-
-          attribute Int8Array int8ArrayAttr;
-          undefined int8ArrayMethod(Int8Array arg1, Int8Array? arg2, sequence<Int8Array> arg3);
-
-          attribute Uint8Array uint8ArrayAttr;
-          undefined uint8ArrayMethod(Uint8Array arg1, Uint8Array? arg2, sequence<Uint8Array> arg3);
-
-          attribute Uint8ClampedArray uint8ClampedArrayAttr;
-          undefined uint8ClampedArrayMethod(Uint8ClampedArray arg1, Uint8ClampedArray? arg2, sequence<Uint8ClampedArray> arg3);
-
-          attribute Int16Array int16ArrayAttr;
-          undefined int16ArrayMethod(Int16Array arg1, Int16Array? arg2, sequence<Int16Array> arg3);
-
-          attribute Uint16Array uint16ArrayAttr;
-          undefined uint16ArrayMethod(Uint16Array arg1, Uint16Array? arg2, sequence<Uint16Array> arg3);
-
-          attribute Int32Array int32ArrayAttr;
-          undefined int32ArrayMethod(Int32Array arg1, Int32Array? arg2, sequence<Int32Array> arg3);
-
-          attribute Uint32Array uint32ArrayAttr;
-          undefined uint32ArrayMethod(Uint32Array arg1, Uint32Array? arg2, sequence<Uint32Array> arg3);
-
-          attribute Float32Array float32ArrayAttr;
-          undefined float32ArrayMethod(Float32Array arg1, Float32Array? arg2, sequence<Float32Array> arg3);
-
-          attribute Float64Array float64ArrayAttr;
-          undefined float64ArrayMethod(Float64Array arg1, Float64Array? arg2, sequence<Float64Array> arg3);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    iface = results[0]
-
-    harness.ok(True, "TestArrayBuffer interface parsed without error")
-    harness.check(len(iface.members), 22, "Interface should have twenty two members")
-
-    members = iface.members
-
-    def checkStuff(attr, method, t):
-        harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Expect an IDLAttribute")
-        harness.ok(isinstance(method, WebIDL.IDLMethod), "Expect an IDLMethod")
-
-        harness.check(str(attr.type), t, "Expect an ArrayBuffer type")
-        harness.ok(attr.type.isSpiderMonkeyInterface(), "Should test as a js interface")
-
-        (retType, arguments) = method.signatures()[0]
-        harness.ok(retType.isUndefined(), "Should have an undefined return type")
-        harness.check(len(arguments), 3, "Expect 3 arguments")
-
-        harness.check(str(arguments[0].type), t, "Expect an ArrayBuffer type")
-        harness.ok(
-            arguments[0].type.isSpiderMonkeyInterface(), "Should test as a js interface"
-        )
-
-        harness.check(
-            str(arguments[1].type), t + "OrNull", "Expect an ArrayBuffer type"
-        )
-        harness.ok(
-            arguments[1].type.inner.isSpiderMonkeyInterface(),
-            "Should test as a js interface",
-        )
-
-        harness.check(
-            str(arguments[2].type), t + "Sequence", "Expect an ArrayBuffer type"
-        )
-        harness.ok(
-            arguments[2].type.inner.isSpiderMonkeyInterface(),
-            "Should test as a js interface",
-        )
-
-    checkStuff(members[0], members[1], "ArrayBuffer")
-    checkStuff(members[2], members[3], "ArrayBufferView")
-    checkStuff(members[4], members[5], "Int8Array")
-    checkStuff(members[6], members[7], "Uint8Array")
-    checkStuff(members[8], members[9], "Uint8ClampedArray")
-    checkStuff(members[10], members[11], "Int16Array")
-    checkStuff(members[12], members[13], "Uint16Array")
-    checkStuff(members[14], members[15], "Int32Array")
-    checkStuff(members[16], members[17], "Uint32Array")
-    checkStuff(members[18], members[19], "Float32Array")
-    checkStuff(members[20], members[21], "Float64Array")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_attr.py b/components/script/dom/bindings/codegen/parser/tests/test_attr.py
deleted file mode 100644
index e19689a81a9..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_attr.py
+++ /dev/null
@@ -1,199 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    testData = [
-        ("::TestAttr%s::b", "b", "Byte%s", False),
-        ("::TestAttr%s::rb", "rb", "Byte%s", True),
-        ("::TestAttr%s::o", "o", "Octet%s", False),
-        ("::TestAttr%s::ro", "ro", "Octet%s", True),
-        ("::TestAttr%s::s", "s", "Short%s", False),
-        ("::TestAttr%s::rs", "rs", "Short%s", True),
-        ("::TestAttr%s::us", "us", "UnsignedShort%s", False),
-        ("::TestAttr%s::rus", "rus", "UnsignedShort%s", True),
-        ("::TestAttr%s::l", "l", "Long%s", False),
-        ("::TestAttr%s::rl", "rl", "Long%s", True),
-        ("::TestAttr%s::ul", "ul", "UnsignedLong%s", False),
-        ("::TestAttr%s::rul", "rul", "UnsignedLong%s", True),
-        ("::TestAttr%s::ll", "ll", "LongLong%s", False),
-        ("::TestAttr%s::rll", "rll", "LongLong%s", True),
-        ("::TestAttr%s::ull", "ull", "UnsignedLongLong%s", False),
-        ("::TestAttr%s::rull", "rull", "UnsignedLongLong%s", True),
-        ("::TestAttr%s::str", "str", "String%s", False),
-        ("::TestAttr%s::rstr", "rstr", "String%s", True),
-        ("::TestAttr%s::obj", "obj", "Object%s", False),
-        ("::TestAttr%s::robj", "robj", "Object%s", True),
-        ("::TestAttr%s::object", "object", "Object%s", False),
-        ("::TestAttr%s::f", "f", "Float%s", False),
-        ("::TestAttr%s::rf", "rf", "Float%s", True),
-    ]
-
-    parser.parse(
-        """
-        interface TestAttr {
-          attribute byte b;
-          readonly attribute byte rb;
-          attribute octet o;
-          readonly attribute octet ro;
-          attribute short s;
-          readonly attribute short rs;
-          attribute unsigned short us;
-          readonly attribute unsigned short rus;
-          attribute long l;
-          readonly attribute long rl;
-          attribute unsigned long ul;
-          readonly attribute unsigned long rul;
-          attribute long long ll;
-          readonly attribute long long rll;
-          attribute unsigned long long ull;
-          readonly attribute unsigned long long rull;
-          attribute DOMString str;
-          readonly attribute DOMString rstr;
-          attribute object obj;
-          readonly attribute object robj;
-          attribute object _object;
-          attribute float f;
-          readonly attribute float rf;
-        };
-
-        interface TestAttrNullable {
-          attribute byte? b;
-          readonly attribute byte? rb;
-          attribute octet? o;
-          readonly attribute octet? ro;
-          attribute short? s;
-          readonly attribute short? rs;
-          attribute unsigned short? us;
-          readonly attribute unsigned short? rus;
-          attribute long? l;
-          readonly attribute long? rl;
-          attribute unsigned long? ul;
-          readonly attribute unsigned long? rul;
-          attribute long long? ll;
-          readonly attribute long long? rll;
-          attribute unsigned long long? ull;
-          readonly attribute unsigned long long? rull;
-          attribute DOMString? str;
-          readonly attribute DOMString? rstr;
-          attribute object? obj;
-          readonly attribute object? robj;
-          attribute object? _object;
-          attribute float? f;
-          readonly attribute float? rf;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    def checkAttr(attr, QName, name, type, readonly):
-        harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-        harness.ok(attr.isAttr(), "Attr is an Attr")
-        harness.ok(not attr.isMethod(), "Attr is not an method")
-        harness.ok(not attr.isConst(), "Attr is not a const")
-        harness.check(attr.identifier.QName(), QName, "Attr has the right QName")
-        harness.check(attr.identifier.name, name, "Attr has the right name")
-        harness.check(str(attr.type), type, "Attr has the right type")
-        harness.check(attr.readonly, readonly, "Attr's readonly state is correct")
-
-    harness.ok(True, "TestAttr interface parsed without error.")
-    harness.check(len(results), 2, "Should be two productions.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestAttr", "Interface has the right QName"
-    )
-    harness.check(iface.identifier.name, "TestAttr", "Interface has the right name")
-    harness.check(
-        len(iface.members), len(testData), "Expect %s members" % len(testData)
-    )
-
-    attrs = iface.members
-
-    for i in range(len(attrs)):
-        data = testData[i]
-        attr = attrs[i]
-        (QName, name, type, readonly) = data
-        checkAttr(attr, QName % "", name, type % "", readonly)
-
-    iface = results[1]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestAttrNullable", "Interface has the right QName"
-    )
-    harness.check(
-        iface.identifier.name, "TestAttrNullable", "Interface has the right name"
-    )
-    harness.check(
-        len(iface.members), len(testData), "Expect %s members" % len(testData)
-    )
-
-    attrs = iface.members
-
-    for i in range(len(attrs)):
-        data = testData[i]
-        attr = attrs[i]
-        (QName, name, type, readonly) = data
-        checkAttr(attr, QName % "Nullable", name, type % "OrNull", readonly)
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [SetterThrows] readonly attribute boolean foo;
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should not allow [SetterThrows] on readonly attributes")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throw] readonly attribute boolean foo;
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should spell [Throws] correctly")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [SameObject] readonly attribute boolean foo;
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw, "Should not allow [SameObject] on attributes not of interface type"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [SameObject] readonly attribute A foo;
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(not threw, "Should allow [SameObject] on attributes of interface type")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_attr_sequence_type.py b/components/script/dom/bindings/codegen/parser/tests/test_attr_sequence_type.py
deleted file mode 100644
index f3249de900a..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_attr_sequence_type.py
+++ /dev/null
@@ -1,77 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface AttrSequenceType {
-              attribute sequence<object> foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Attribute type must not be a sequence type")
-
-    parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface AttrUnionWithSequenceType {
-              attribute (sequence<object> or DOMString) foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Attribute type must not be a union with a sequence member type")
-
-    parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface AttrNullableUnionWithSequenceType {
-              attribute (sequence<object>? or DOMString) foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Attribute type must not be a union with a nullable sequence " "member type",
-    )
-
-    parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface AttrUnionWithUnionWithSequenceType {
-              attribute ((sequence<object> or DOMString) or AttrUnionWithUnionWithSequenceType) foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Attribute type must not be a union type with a union member "
-        "type that has a sequence member type",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_attributes_on_types.py b/components/script/dom/bindings/codegen/parser/tests/test_attributes_on_types.py
deleted file mode 100644
index 97a7f47859a..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_attributes_on_types.py
+++ /dev/null
@@ -1,570 +0,0 @@
-# Import the WebIDL module, so we can do isinstance checks and whatnot
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    # Basic functionality
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [EnforceRange] long Foo;
-            typedef [Clamp] long Bar;
-            typedef [LegacyNullToEmptyString] DOMString Baz;
-            dictionary A {
-                required [EnforceRange] long a;
-                required [Clamp] long b;
-                [ChromeOnly, EnforceRange] long c;
-                Foo d;
-            };
-            interface B {
-                attribute Foo typedefFoo;
-                attribute [EnforceRange] long foo;
-                attribute [Clamp] long bar;
-                attribute [LegacyNullToEmptyString] DOMString baz;
-                undefined method([EnforceRange] long foo, [Clamp] long bar,
-                                 [LegacyNullToEmptyString] DOMString baz);
-                undefined method2(optional [EnforceRange] long foo, optional [Clamp] long bar,
-                                  optional [LegacyNullToEmptyString] DOMString baz);
-                undefined method3(optional [LegacyNullToEmptyString] UTF8String foo = "");
-            };
-            interface C {
-                attribute [EnforceRange] long? foo;
-                attribute [Clamp] long? bar;
-                undefined method([EnforceRange] long? foo, [Clamp] long? bar);
-                undefined method2(optional [EnforceRange] long? foo, optional [Clamp] long? bar);
-            };
-            interface Setlike {
-                setlike<[Clamp] long>;
-            };
-            interface Maplike {
-                maplike<[Clamp] long, [EnforceRange] long>;
-            };
-            interface Iterable {
-                iterable<[Clamp] long, [EnforceRange] long>;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(not threw, "Should not have thrown on parsing normal")
-    if not threw:
-        harness.check(
-            results[0].innerType.hasEnforceRange(), True, "Foo is [EnforceRange]"
-        )
-        harness.check(results[1].innerType.hasClamp(), True, "Bar is [Clamp]")
-        harness.check(
-            results[2].innerType.legacyNullToEmptyString,
-            True,
-            "Baz is [LegacyNullToEmptyString]",
-        )
-        A = results[3]
-        harness.check(
-            A.members[0].type.hasEnforceRange(), True, "A.a is [EnforceRange]"
-        )
-        harness.check(A.members[1].type.hasClamp(), True, "A.b is [Clamp]")
-        harness.check(
-            A.members[2].type.hasEnforceRange(), True, "A.c is [EnforceRange]"
-        )
-        harness.check(
-            A.members[3].type.hasEnforceRange(), True, "A.d is [EnforceRange]"
-        )
-        B = results[4]
-        harness.check(
-            B.members[0].type.hasEnforceRange(), True, "B.typedefFoo is [EnforceRange]"
-        )
-        harness.check(
-            B.members[1].type.hasEnforceRange(), True, "B.foo is [EnforceRange]"
-        )
-        harness.check(B.members[2].type.hasClamp(), True, "B.bar is [Clamp]")
-        harness.check(
-            B.members[3].type.legacyNullToEmptyString,
-            True,
-            "B.baz is [LegacyNullToEmptyString]",
-        )
-        method = B.members[4].signatures()[0][1]
-        harness.check(
-            method[0].type.hasEnforceRange(),
-            True,
-            "foo argument of method is [EnforceRange]",
-        )
-        harness.check(
-            method[1].type.hasClamp(), True, "bar argument of method is [Clamp]"
-        )
-        harness.check(
-            method[2].type.legacyNullToEmptyString,
-            True,
-            "baz argument of method is [LegacyNullToEmptyString]",
-        )
-        method2 = B.members[5].signatures()[0][1]
-        harness.check(
-            method2[0].type.hasEnforceRange(),
-            True,
-            "foo argument of method2 is [EnforceRange]",
-        )
-        harness.check(
-            method2[1].type.hasClamp(), True, "bar argument of method2 is [Clamp]"
-        )
-        harness.check(
-            method2[2].type.legacyNullToEmptyString,
-            True,
-            "baz argument of method2 is [LegacyNullToEmptyString]",
-        )
-
-        method3 = B.members[6].signatures()[0][1]
-        harness.check(
-            method3[0].type.legacyNullToEmptyString,
-            True,
-            "bar argument of method2 is [LegacyNullToEmptyString]",
-        )
-        harness.check(
-            method3[0].defaultValue.type.isUTF8String(),
-            True,
-            "default value of bar argument of method2 is correctly coerced to UTF8String",
-        )
-
-        C = results[5]
-        harness.ok(C.members[0].type.nullable(), "C.foo is nullable")
-        harness.ok(C.members[0].type.hasEnforceRange(), "C.foo has [EnforceRange]")
-        harness.ok(C.members[1].type.nullable(), "C.bar is nullable")
-        harness.ok(C.members[1].type.hasClamp(), "C.bar has [Clamp]")
-        method = C.members[2].signatures()[0][1]
-        harness.ok(method[0].type.nullable(), "foo argument of method is nullable")
-        harness.ok(
-            method[0].type.hasEnforceRange(),
-            "foo argument of method has [EnforceRange]",
-        )
-        harness.ok(method[1].type.nullable(), "bar argument of method is nullable")
-        harness.ok(method[1].type.hasClamp(), "bar argument of method has [Clamp]")
-        method2 = C.members[3].signatures()[0][1]
-        harness.ok(method2[0].type.nullable(), "foo argument of method2 is nullable")
-        harness.ok(
-            method2[0].type.hasEnforceRange(),
-            "foo argument of method2 has [EnforceRange]",
-        )
-        harness.ok(method2[1].type.nullable(), "bar argument of method2 is nullable")
-        harness.ok(method2[1].type.hasClamp(), "bar argument of method2 has [Clamp]")
-
-    # Test [AllowShared]
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [AllowShared] ArrayBufferView Foo;
-            dictionary A {
-                required [AllowShared] ArrayBufferView a;
-                [ChromeOnly, AllowShared] ArrayBufferView b;
-                Foo c;
-            };
-            interface B {
-                attribute Foo typedefFoo;
-                attribute [AllowShared] ArrayBufferView foo;
-                undefined method([AllowShared] ArrayBufferView foo);
-                undefined method2(optional [AllowShared] ArrayBufferView foo);
-            };
-            interface C {
-                attribute [AllowShared] ArrayBufferView? foo;
-                undefined method([AllowShared] ArrayBufferView? foo);
-                undefined method2(optional [AllowShared] ArrayBufferView? foo);
-            };
-            interface Setlike {
-                setlike<[AllowShared] ArrayBufferView>;
-            };
-            interface Maplike {
-                maplike<[Clamp] long, [AllowShared] ArrayBufferView>;
-            };
-            interface Iterable {
-                iterable<[Clamp] long, [AllowShared] ArrayBufferView>;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(not threw, "Should not have thrown on parsing normal")
-    if not threw:
-        harness.ok(results[0].innerType.hasAllowShared(), "Foo is [AllowShared]")
-        A = results[1]
-        harness.ok(A.members[0].type.hasAllowShared(), "A.a is [AllowShared]")
-        harness.ok(A.members[1].type.hasAllowShared(), "A.b is [AllowShared]")
-        harness.ok(A.members[2].type.hasAllowShared(), "A.c is [AllowShared]")
-        B = results[2]
-        harness.ok(B.members[0].type.hasAllowShared(), "B.typedefFoo is [AllowShared]")
-        harness.ok(B.members[1].type.hasAllowShared(), "B.foo is [AllowShared]")
-        method = B.members[2].signatures()[0][1]
-        harness.ok(
-            method[0].type.hasAllowShared(), "foo argument of method is [AllowShared]"
-        )
-        method2 = B.members[3].signatures()[0][1]
-        harness.ok(
-            method2[0].type.hasAllowShared(), "foo argument of method2 is [AllowShared]"
-        )
-        C = results[3]
-        harness.ok(C.members[0].type.nullable(), "C.foo is nullable")
-        harness.ok(C.members[0].type.hasAllowShared(), "C.foo is [AllowShared]")
-        method = C.members[1].signatures()[0][1]
-        harness.ok(method[0].type.nullable(), "foo argument of method is nullable")
-        harness.ok(
-            method[0].type.hasAllowShared(), "foo argument of method is [AllowShared]"
-        )
-        method2 = C.members[2].signatures()[0][1]
-        harness.ok(method2[0].type.nullable(), "foo argument of method2 is nullable")
-        harness.ok(
-            method2[0].type.hasAllowShared(), "foo argument of method2 is [AllowShared]"
-        )
-
-    ATTRIBUTES = [
-        ("[Clamp]", "long"),
-        ("[EnforceRange]", "long"),
-        ("[LegacyNullToEmptyString]", "DOMString"),
-        ("[AllowShared]", "ArrayBufferView"),
-    ]
-    TEMPLATES = [
-        (
-            "required dictionary members",
-            """
-            dictionary Foo {
-                %s required %s foo;
-            };
-        """,
-        ),
-        (
-            "optional arguments",
-            """
-            interface Foo {
-                undefined foo(%s optional %s foo);
-            };
-        """,
-        ),
-        (
-            "typedefs",
-            """
-            %s typedef %s foo;
-        """,
-        ),
-        (
-            "attributes",
-            """
-            interface Foo {
-            %s attribute %s foo;
-            };
-        """,
-        ),
-        (
-            "readonly attributes",
-            """
-            interface Foo {
-                readonly attribute %s %s foo;
-            };
-        """,
-        ),
-        (
-            "readonly unresolved attributes",
-            """
-            interface Foo {
-              readonly attribute Bar baz;
-            };
-            typedef %s %s Bar;
-        """,
-        ),
-        (
-            "method",
-            """
-            interface Foo {
-              %s %s foo();
-            };
-        """,
-        ),
-        (
-            "interface",
-            """
-            %s
-            interface Foo {
-              attribute %s foo;
-            };
-        """,
-        ),
-        (
-            "partial interface",
-            """
-            interface Foo {
-              undefined foo();
-            };
-            %s
-            partial interface Foo {
-              attribute %s bar;
-            };
-        """,
-        ),
-        (
-            "interface mixin",
-            """
-            %s
-            interface mixin Foo {
-              attribute %s foo;
-            };
-        """,
-        ),
-        (
-            "namespace",
-            """
-            %s
-            namespace Foo {
-              attribute %s foo;
-            };
-        """,
-        ),
-        (
-            "partial namespace",
-            """
-            namespace Foo {
-              undefined foo();
-            };
-            %s
-            partial namespace Foo {
-              attribute %s bar;
-            };
-        """,
-        ),
-        (
-            "dictionary",
-            """
-            %s
-            dictionary Foo {
-              %s foo;
-            };
-        """,
-        ),
-    ]
-
-    for (name, template) in TEMPLATES:
-        parser = parser.reset()
-        threw = False
-        try:
-            parser.parse(template % ("", "long"))
-            parser.finish()
-        except:
-            threw = True
-        harness.ok(not threw, "Template for %s parses without attributes" % name)
-        for (attribute, type) in ATTRIBUTES:
-            parser = parser.reset()
-            threw = False
-            try:
-                parser.parse(template % (attribute, type))
-                parser.finish()
-            except:
-                threw = True
-            harness.ok(threw, "Should not allow %s on %s" % (attribute, name))
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [Clamp, EnforceRange] long Foo;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow mixing [Clamp] and [EnforceRange]")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [EnforceRange, Clamp] long Foo;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow mixing [Clamp] and [EnforceRange]")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [Clamp] long Foo;
-            typedef [EnforceRange] Foo bar;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow mixing [Clamp] and [EnforceRange] via typedefs")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [EnforceRange] long Foo;
-            typedef [Clamp] Foo bar;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow mixing [Clamp] and [EnforceRange] via typedefs")
-
-    TYPES = [
-        "DOMString",
-        "unrestricted float",
-        "float",
-        "unrestricted double",
-        "double",
-    ]
-
-    for type in TYPES:
-        parser = parser.reset()
-        threw = False
-        try:
-            parser.parse(
-                """
-                typedef [Clamp] %s Foo;
-            """
-                % type
-            )
-            parser.finish()
-        except:
-            threw = True
-
-        harness.ok(threw, "Should not allow [Clamp] on %s" % type)
-
-        parser = parser.reset()
-        threw = False
-        try:
-            parser.parse(
-                """
-                typedef [EnforceRange] %s Foo;
-            """
-                % type
-            )
-            parser.finish()
-        except:
-            threw = True
-
-        harness.ok(threw, "Should not allow [EnforceRange] on %s" % type)
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [LegacyNullToEmptyString] long Foo;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow [LegacyNullToEmptyString] on long")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [LegacyNullToEmptyString] JSString Foo;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow [LegacyNullToEmptyString] on JSString")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [LegacyNullToEmptyString] DOMString? Foo;
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not allow [LegacyNullToEmptyString] on nullable DOMString"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [AllowShared] DOMString Foo;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[AllowShared] only allowed on buffer source types")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            typedef [AllowShared=something] ArrayBufferView Foo;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[AllowShared] must take no arguments")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-               undefined foo([Clamp] Bar arg);
-            };
-            typedef long Bar;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(not threw, "Should allow type attributes on unresolved types")
-    harness.check(
-        results[0].members[0].signatures()[0][1][0].type.hasClamp(),
-        True,
-        "Unresolved types with type attributes should correctly resolve with attributes",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-               undefined foo(Bar arg);
-            };
-            typedef [Clamp] long Bar;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(not threw, "Should allow type attributes on typedefs")
-    harness.check(
-        results[0].members[0].signatures()[0][1][0].type.hasClamp(),
-        True,
-        "Unresolved types that resolve to typedefs with attributes should correctly resolve with attributes",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_builtin_filename.py b/components/script/dom/bindings/codegen/parser/tests/test_builtin_filename.py
deleted file mode 100644
index 6c913bba822..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_builtin_filename.py
+++ /dev/null
@@ -1,14 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface Test {
-          attribute long b;
-        };
-    """
-    )
-
-    attr = parser.finish()[0].members[0]
-    harness.check(attr.type.filename(), "<builtin>", "Filename on builtin type")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_builtins.py b/components/script/dom/bindings/codegen/parser/tests/test_builtins.py
deleted file mode 100644
index a75a12e8143..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_builtins.py
+++ /dev/null
@@ -1,59 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestBuiltins {
-          attribute boolean b;
-          attribute byte s8;
-          attribute octet u8;
-          attribute short s16;
-          attribute unsigned short u16;
-          attribute long s32;
-          attribute unsigned long u32;
-          attribute long long s64;
-          attribute unsigned long long u64;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestBuiltins interface parsed without error.")
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-    iface = results[0]
-    harness.check(
-        iface.identifier.QName(), "::TestBuiltins", "Interface has the right QName"
-    )
-    harness.check(iface.identifier.name, "TestBuiltins", "Interface has the right name")
-    harness.check(iface.parent, None, "Interface has no parent")
-
-    members = iface.members
-    harness.check(len(members), 9, "Should be one production")
-
-    names = ["b", "s8", "u8", "s16", "u16", "s32", "u32", "s64", "u64", "ts"]
-    types = [
-        "Boolean",
-        "Byte",
-        "Octet",
-        "Short",
-        "UnsignedShort",
-        "Long",
-        "UnsignedLong",
-        "LongLong",
-        "UnsignedLongLong",
-        "UnsignedLongLong",
-    ]
-    for i in range(9):
-        attr = members[i]
-        harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-        harness.check(
-            attr.identifier.QName(),
-            "::TestBuiltins::" + names[i],
-            "Attr has correct QName",
-        )
-        harness.check(attr.identifier.name, names[i], "Attr has correct name")
-        harness.check(str(attr.type), types[i], "Attr type is the correct name")
-        harness.ok(attr.type.isPrimitive(), "Should be a primitive type")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_bytestring.py b/components/script/dom/bindings/codegen/parser/tests/test_bytestring.py
deleted file mode 100644
index a6f9f6ab9cb..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_bytestring.py
+++ /dev/null
@@ -1,125 +0,0 @@
-# -*- coding: UTF-8 -*-
-
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestByteString {
-          attribute ByteString bs;
-          attribute DOMString ds;
-          };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestByteString interface parsed without error.")
-
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-    iface = results[0]
-    harness.check(
-        iface.identifier.QName(), "::TestByteString", "Interface has the right QName"
-    )
-    harness.check(
-        iface.identifier.name, "TestByteString", "Interface has the right name"
-    )
-    harness.check(iface.parent, None, "Interface has no parent")
-
-    members = iface.members
-    harness.check(len(members), 2, "Should be two productions")
-
-    attr = members[0]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    harness.check(
-        attr.identifier.QName(), "::TestByteString::bs", "Attr has correct QName"
-    )
-    harness.check(attr.identifier.name, "bs", "Attr has correct name")
-    harness.check(str(attr.type), "ByteString", "Attr type is the correct name")
-    harness.ok(attr.type.isByteString(), "Should be ByteString type")
-    harness.ok(attr.type.isString(), "Should be String collective type")
-    harness.ok(not attr.type.isDOMString(), "Should be not be DOMString type")
-
-    # now check we haven't broken DOMStrings in the process.
-    attr = members[1]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    harness.check(
-        attr.identifier.QName(), "::TestByteString::ds", "Attr has correct QName"
-    )
-    harness.check(attr.identifier.name, "ds", "Attr has correct name")
-    harness.check(str(attr.type), "String", "Attr type is the correct name")
-    harness.ok(attr.type.isDOMString(), "Should be DOMString type")
-    harness.ok(attr.type.isString(), "Should be String collective type")
-    harness.ok(not attr.type.isByteString(), "Should be not be ByteString type")
-
-    # Cannot represent constant ByteString in IDL.
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface ConstByteString {
-              const ByteString foo = "hello"
-              };
-        """
-        )
-    except WebIDL.WebIDLError:
-        threw = True
-    harness.ok(
-        threw, "Should have thrown a WebIDL error for ByteString default in interface"
-    )
-
-    # Can have optional ByteStrings with default values
-    try:
-        parser.parse(
-            """
-            interface OptionalByteString {
-              undefined passByteString(optional ByteString arg = "hello");
-              };
-        """
-        )
-        results2 = parser.finish()
-    except WebIDL.WebIDLError as e:
-        harness.ok(
-            False,
-            "Should not have thrown a WebIDL error for ByteString "
-            "default in dictionary. " + str(e),
-        )
-
-    # Can have a default ByteString value in a dictionary
-    try:
-        parser.parse(
-            """
-        dictionary OptionalByteStringDict {
-          ByteString item = "some string";
-        };
-        """
-        )
-        results3 = parser.finish()
-    except WebIDL.WebIDLError as e:
-        harness.ok(
-            False,
-            "Should not have thrown a WebIDL error for ByteString "
-            "default in dictionary. " + str(e),
-        )
-
-    # Don't allow control characters in ByteString literals
-    threw = False
-    try:
-        parser.parse(
-            """
-        dictionary OptionalByteStringDict2 {
-          ByteString item = "\x03";
-        };
-        """
-        )
-        results4 = parser.finish()
-    except WebIDL.WebIDLError as e:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown a WebIDL error for invalid ByteString "
-        "default in dictionary",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_callback.py b/components/script/dom/bindings/codegen/parser/tests/test_callback.py
deleted file mode 100644
index 407644a6a8d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_callback.py
+++ /dev/null
@@ -1,42 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestCallback {
-          attribute CallbackType? listener;
-        };
-
-        callback CallbackType = boolean (unsigned long arg);
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestCallback interface parsed without error.")
-    harness.check(len(results), 2, "Should be two productions.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestCallback", "Interface has the right QName"
-    )
-    harness.check(iface.identifier.name, "TestCallback", "Interface has the right name")
-    harness.check(len(iface.members), 1, "Expect %s members" % 1)
-
-    attr = iface.members[0]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    harness.ok(attr.isAttr(), "Should be an attribute")
-    harness.ok(not attr.isMethod(), "Attr is not an method")
-    harness.ok(not attr.isConst(), "Attr is not a const")
-    harness.check(
-        attr.identifier.QName(), "::TestCallback::listener", "Attr has the right QName"
-    )
-    harness.check(attr.identifier.name, "listener", "Attr has the right name")
-    t = attr.type
-    harness.ok(not isinstance(t, WebIDL.IDLWrapperType), "Attr has the right type")
-    harness.ok(isinstance(t, WebIDL.IDLNullableType), "Attr has the right type")
-    harness.ok(t.isCallback(), "Attr has the right type")
-
-    callback = results[1]
-    harness.ok(not callback.isConstructor(), "callback is not constructor")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_callback_constructor.py b/components/script/dom/bindings/codegen/parser/tests/test_callback_constructor.py
deleted file mode 100644
index 832a92bb147..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_callback_constructor.py
+++ /dev/null
@@ -1,84 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestCallbackConstructor {
-          attribute CallbackConstructorType? constructorAttribute;
-        };
-
-        callback constructor CallbackConstructorType = TestCallbackConstructor (unsigned long arg);
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestCallbackConstructor interface parsed without error.")
-    harness.check(len(results), 2, "Should be two productions.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(),
-        "::TestCallbackConstructor",
-        "Interface has the right QName",
-    )
-    harness.check(
-        iface.identifier.name, "TestCallbackConstructor", "Interface has the right name"
-    )
-    harness.check(len(iface.members), 1, "Expect %s members" % 1)
-
-    attr = iface.members[0]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    harness.ok(attr.isAttr(), "Should be an attribute")
-    harness.ok(not attr.isMethod(), "Attr is not an method")
-    harness.ok(not attr.isConst(), "Attr is not a const")
-    harness.check(
-        attr.identifier.QName(),
-        "::TestCallbackConstructor::constructorAttribute",
-        "Attr has the right QName",
-    )
-    harness.check(
-        attr.identifier.name, "constructorAttribute", "Attr has the right name"
-    )
-    t = attr.type
-    harness.ok(not isinstance(t, WebIDL.IDLWrapperType), "Attr has the right type")
-    harness.ok(isinstance(t, WebIDL.IDLNullableType), "Attr has the right type")
-    harness.ok(t.isCallback(), "Attr has the right type")
-
-    callback = results[1]
-    harness.ok(callback.isConstructor(), "Callback is constructor")
-
-    parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyTreatNonObjectAsNull]
-            callback constructor CallbackConstructorType = object ();
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should throw on LegacyTreatNonObjectAsNull callback constructors"
-    )
-
-    parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [MOZ_CAN_RUN_SCRIPT_BOUNDARY]
-            callback constructor CallbackConstructorType = object ();
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not permit MOZ_CAN_RUN_SCRIPT_BOUNDARY callback constructors"
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_callback_interface.py b/components/script/dom/bindings/codegen/parser/tests/test_callback_interface.py
deleted file mode 100644
index 0d657f48032..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_callback_interface.py
+++ /dev/null
@@ -1,106 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        callback interface TestCallbackInterface {
-          attribute boolean bool;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    iface = results[0]
-
-    harness.ok(iface.isCallback(), "Interface should be a callback")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestInterface {
-            };
-            callback interface TestCallbackInterface : TestInterface {
-              attribute boolean bool;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow non-callback parent of callback interface")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestInterface : TestCallbackInterface {
-            };
-            callback interface TestCallbackInterface {
-              attribute boolean bool;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow callback parent of non-callback interface")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        callback interface TestCallbackInterface1 {
-          undefined foo();
-        };
-        callback interface TestCallbackInterface2 {
-          undefined foo(DOMString arg);
-          undefined foo(TestCallbackInterface1 arg);
-        };
-        callback interface TestCallbackInterface3 {
-          undefined foo(DOMString arg);
-          undefined foo(TestCallbackInterface1 arg);
-          static undefined bar();
-        };
-        callback interface TestCallbackInterface4 {
-          undefined foo(DOMString arg);
-          undefined foo(TestCallbackInterface1 arg);
-          static undefined bar();
-          const long baz = 5;
-        };
-        callback interface TestCallbackInterface5 {
-          static attribute boolean bool;
-          undefined foo();
-        };
-        callback interface TestCallbackInterface6 {
-          undefined foo(DOMString arg);
-          undefined foo(TestCallbackInterface1 arg);
-          undefined bar();
-        };
-        callback interface TestCallbackInterface7 {
-          static attribute boolean bool;
-        };
-        callback interface TestCallbackInterface8 {
-          attribute boolean bool;
-        };
-        callback interface TestCallbackInterface9 : TestCallbackInterface1 {
-          undefined foo();
-        };
-        callback interface TestCallbackInterface10 : TestCallbackInterface1 {
-          undefined bar();
-        };
-    """
-    )
-    results = parser.finish()
-    for (i, iface) in enumerate(results):
-        harness.check(
-            iface.isSingleOperationInterface(),
-            i < 4,
-            "Interface %s should be a single operation interface"
-            % iface.identifier.name,
-        )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_cereactions.py b/components/script/dom/bindings/codegen/parser/tests/test_cereactions.py
deleted file mode 100644
index c56c3dbde10..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_cereactions.py
+++ /dev/null
@@ -1,157 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              [CEReactions(DOMString a)] undefined foo(boolean arg2);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] with an argument")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              [CEReactions(DOMString b)] readonly attribute boolean bar;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] with an argument")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              [CEReactions] attribute boolean bar;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as e:
-        harness.ok(
-            False,
-            "Shouldn't have thrown for [CEReactions] used on writable attribute. %s"
-            % e,
-        )
-        threw = True
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              [CEReactions] undefined foo(boolean arg2);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as e:
-        harness.ok(
-            False,
-            "Shouldn't have thrown for [CEReactions] used on regular operations. %s"
-            % e,
-        )
-        threw = True
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              [CEReactions] readonly attribute boolean A;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should have thrown for [CEReactions] used on a readonly attribute"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [CEReactions]
-            interface Foo {
-            }
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] used on a interface")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Foo {
-            [CEReactions] getter any(DOMString name);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] used on a named getter")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Foo {
-            [CEReactions] legacycaller double compute(double x);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] used on a legacycaller")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Foo {
-            [CEReactions] stringifier DOMString ();
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for [CEReactions] used on a stringifier")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_conditional_dictionary_member.py b/components/script/dom/bindings/codegen/parser/tests/test_conditional_dictionary_member.py
deleted file mode 100644
index 2aef8ebe8ff..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_conditional_dictionary_member.py
+++ /dev/null
@@ -1,128 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      dictionary Dict {
-        any foo;
-        [ChromeOnly] any bar;
-      };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should have a dictionary")
-    members = results[0].members
-    harness.check(len(members), 2, "Should have two members")
-    # Note that members are ordered lexicographically, so "bar" comes
-    # before "foo".
-    harness.ok(
-        members[0].getExtendedAttribute("ChromeOnly"), "First member is not ChromeOnly"
-    )
-    harness.ok(
-        not members[1].getExtendedAttribute("ChromeOnly"), "Second member is ChromeOnly"
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      dictionary Dict {
-        any foo;
-        any bar;
-      };
-
-      interface Iface {
-        [Constant, Cached] readonly attribute Dict dict;
-      };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 2, "Should have a dictionary and an interface")
-
-    parser = parser.reset()
-    exception = None
-    try:
-        parser.parse(
-            """
-        dictionary Dict {
-          any foo;
-          [ChromeOnly] any bar;
-        };
-
-        interface Iface {
-          [Constant, Cached] readonly attribute Dict dict;
-        };
-      """
-        )
-        results = parser.finish()
-    except Exception as e:
-        exception = e
-
-    harness.ok(exception, "Should have thrown.")
-    harness.check(
-        exception.message,
-        "[Cached] and [StoreInSlot] must not be used on an attribute "
-        "whose type contains a [ChromeOnly] dictionary member",
-        "Should have thrown the right exception",
-    )
-
-    parser = parser.reset()
-    exception = None
-    try:
-        parser.parse(
-            """
-        dictionary ParentDict {
-          [ChromeOnly] any bar;
-        };
-
-        dictionary Dict : ParentDict {
-          any foo;
-        };
-
-        interface Iface {
-          [Constant, Cached] readonly attribute Dict dict;
-        };
-      """
-        )
-        results = parser.finish()
-    except Exception as e:
-        exception = e
-
-    harness.ok(exception, "Should have thrown (2).")
-    harness.check(
-        exception.message,
-        "[Cached] and [StoreInSlot] must not be used on an attribute "
-        "whose type contains a [ChromeOnly] dictionary member",
-        "Should have thrown the right exception (2)",
-    )
-
-    parser = parser.reset()
-    exception = None
-    try:
-        parser.parse(
-            """
-        dictionary GrandParentDict {
-          [ChromeOnly] any baz;
-        };
-
-        dictionary ParentDict : GrandParentDict {
-          any bar;
-        };
-
-        dictionary Dict : ParentDict {
-          any foo;
-        };
-
-        interface Iface {
-          [Constant, Cached] readonly attribute Dict dict;
-        };
-      """
-        )
-        results = parser.finish()
-    except Exception as e:
-        exception = e
-
-    harness.ok(exception, "Should have thrown (3).")
-    harness.check(
-        exception.message,
-        "[Cached] and [StoreInSlot] must not be used on an attribute "
-        "whose type contains a [ChromeOnly] dictionary member",
-        "Should have thrown the right exception (3)",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_const.py b/components/script/dom/bindings/codegen/parser/tests/test_const.py
deleted file mode 100644
index f2d4b79d467..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_const.py
+++ /dev/null
@@ -1,96 +0,0 @@
-import WebIDL
-
-expected = [
-    ("::TestConsts::zero", "zero", "Byte", 0),
-    ("::TestConsts::b", "b", "Byte", -1),
-    ("::TestConsts::o", "o", "Octet", 2),
-    ("::TestConsts::s", "s", "Short", -3),
-    ("::TestConsts::us", "us", "UnsignedShort", 4),
-    ("::TestConsts::l", "l", "Long", -5),
-    ("::TestConsts::ul", "ul", "UnsignedLong", 6),
-    ("::TestConsts::ull", "ull", "UnsignedLongLong", 7),
-    ("::TestConsts::ll", "ll", "LongLong", -8),
-    ("::TestConsts::t", "t", "Boolean", True),
-    ("::TestConsts::f", "f", "Boolean", False),
-    ("::TestConsts::fl", "fl", "Float", 0.2),
-    ("::TestConsts::db", "db", "Double", 0.2),
-    ("::TestConsts::ufl", "ufl", "UnrestrictedFloat", 0.2),
-    ("::TestConsts::udb", "udb", "UnrestrictedDouble", 0.2),
-    ("::TestConsts::fli", "fli", "Float", 2),
-    ("::TestConsts::dbi", "dbi", "Double", 2),
-    ("::TestConsts::ufli", "ufli", "UnrestrictedFloat", 2),
-    ("::TestConsts::udbi", "udbi", "UnrestrictedDouble", 2),
-]
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestConsts {
-          const byte zero = 0;
-          const byte b = -1;
-          const octet o = 2;
-          const short s = -3;
-          const unsigned short us = 0x4;
-          const long l = -0X5;
-          const unsigned long ul = 6;
-          const unsigned long long ull = 7;
-          const long long ll = -010;
-          const boolean t = true;
-          const boolean f = false;
-          const float fl = 0.2;
-          const double db = 0.2;
-          const unrestricted float ufl = 0.2;
-          const unrestricted double udb = 0.2;
-          const float fli = 2;
-          const double dbi = 2;
-          const unrestricted float ufli = 2;
-          const unrestricted double udbi = 2;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestConsts interface parsed without error.")
-    harness.check(len(results), 1, "Should be one production.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestConsts", "Interface has the right QName"
-    )
-    harness.check(iface.identifier.name, "TestConsts", "Interface has the right name")
-    harness.check(
-        len(iface.members), len(expected), "Expect %s members" % len(expected)
-    )
-
-    for (const, (QName, name, type, value)) in zip(iface.members, expected):
-        harness.ok(isinstance(const, WebIDL.IDLConst), "Should be an IDLConst")
-        harness.ok(const.isConst(), "Const is a const")
-        harness.ok(not const.isAttr(), "Const is not an attr")
-        harness.ok(not const.isMethod(), "Const is not a method")
-        harness.check(const.identifier.QName(), QName, "Const has the right QName")
-        harness.check(const.identifier.name, name, "Const has the right name")
-        harness.check(str(const.type), type, "Const has the right type")
-        harness.ok(const.type.isPrimitive(), "All consts should be primitive")
-        harness.check(
-            str(const.value.type),
-            str(const.type),
-            "Const's value has the same type as the type",
-        )
-        harness.check(const.value.value, value, "Const value has the right value.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface TestConsts {
-            const boolean? zero = 0;
-          };
-        """
-        )
-        parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Nullable types are not allowed for consts.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_constructor.py b/components/script/dom/bindings/codegen/parser/tests/test_constructor.py
deleted file mode 100644
index de5d52f1412..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_constructor.py
+++ /dev/null
@@ -1,594 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    def checkArgument(argument, QName, name, type, optional, variadic):
-        harness.ok(isinstance(argument, WebIDL.IDLArgument), "Should be an IDLArgument")
-        harness.check(
-            argument.identifier.QName(), QName, "Argument has the right QName"
-        )
-        harness.check(argument.identifier.name, name, "Argument has the right name")
-        harness.check(str(argument.type), type, "Argument has the right return type")
-        harness.check(
-            argument.optional, optional, "Argument has the right optional value"
-        )
-        harness.check(
-            argument.variadic, variadic, "Argument has the right variadic value"
-        )
-
-    def checkMethod(
-        method,
-        QName,
-        name,
-        signatures,
-        static=True,
-        getter=False,
-        setter=False,
-        deleter=False,
-        legacycaller=False,
-        stringifier=False,
-        chromeOnly=False,
-        htmlConstructor=False,
-        secureContext=False,
-        pref=None,
-        func=None,
-    ):
-        harness.ok(isinstance(method, WebIDL.IDLMethod), "Should be an IDLMethod")
-        harness.ok(method.isMethod(), "Method is a method")
-        harness.ok(not method.isAttr(), "Method is not an attr")
-        harness.ok(not method.isConst(), "Method is not a const")
-        harness.check(method.identifier.QName(), QName, "Method has the right QName")
-        harness.check(method.identifier.name, name, "Method has the right name")
-        harness.check(method.isStatic(), static, "Method has the correct static value")
-        harness.check(method.isGetter(), getter, "Method has the correct getter value")
-        harness.check(method.isSetter(), setter, "Method has the correct setter value")
-        harness.check(
-            method.isDeleter(), deleter, "Method has the correct deleter value"
-        )
-        harness.check(
-            method.isLegacycaller(),
-            legacycaller,
-            "Method has the correct legacycaller value",
-        )
-        harness.check(
-            method.isStringifier(),
-            stringifier,
-            "Method has the correct stringifier value",
-        )
-        harness.check(
-            method.getExtendedAttribute("ChromeOnly") is not None,
-            chromeOnly,
-            "Method has the correct value for ChromeOnly",
-        )
-        harness.check(
-            method.isHTMLConstructor(),
-            htmlConstructor,
-            "Method has the correct htmlConstructor value",
-        )
-        harness.check(
-            len(method.signatures()),
-            len(signatures),
-            "Method has the correct number of signatures",
-        )
-        harness.check(
-            method.getExtendedAttribute("Pref"),
-            pref,
-            "Method has the correct pref value",
-        )
-        harness.check(
-            method.getExtendedAttribute("Func"),
-            func,
-            "Method has the correct func value",
-        )
-        harness.check(
-            method.getExtendedAttribute("SecureContext") is not None,
-            secureContext,
-            "Method has the correct SecureContext value",
-        )
-
-        sigpairs = zip(method.signatures(), signatures)
-        for (gotSignature, expectedSignature) in sigpairs:
-            (gotRetType, gotArgs) = gotSignature
-            (expectedRetType, expectedArgs) = expectedSignature
-
-            harness.check(
-                str(gotRetType), expectedRetType, "Method has the expected return type."
-            )
-
-            for i in range(0, len(gotArgs)):
-                (QName, name, type, optional, variadic) = expectedArgs[i]
-                checkArgument(gotArgs[i], QName, name, type, optional, variadic)
-
-    def checkResults(results):
-        harness.check(len(results), 3, "Should be three productions")
-        harness.ok(
-            isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface"
-        )
-        harness.ok(
-            isinstance(results[1], WebIDL.IDLInterface), "Should be an IDLInterface"
-        )
-        harness.ok(
-            isinstance(results[2], WebIDL.IDLInterface), "Should be an IDLInterface"
-        )
-
-        checkMethod(
-            results[0].ctor(),
-            "::TestConstructorNoArgs::constructor",
-            "constructor",
-            [("TestConstructorNoArgs (Wrapper)", [])],
-        )
-        harness.check(
-            len(results[0].members), 0, "TestConstructorNoArgs should not have members"
-        )
-        checkMethod(
-            results[1].ctor(),
-            "::TestConstructorWithArgs::constructor",
-            "constructor",
-            [
-                (
-                    "TestConstructorWithArgs (Wrapper)",
-                    [
-                        (
-                            "::TestConstructorWithArgs::constructor::name",
-                            "name",
-                            "String",
-                            False,
-                            False,
-                        )
-                    ],
-                )
-            ],
-        )
-        harness.check(
-            len(results[1].members),
-            0,
-            "TestConstructorWithArgs should not have members",
-        )
-        checkMethod(
-            results[2].ctor(),
-            "::TestConstructorOverloads::constructor",
-            "constructor",
-            [
-                (
-                    "TestConstructorOverloads (Wrapper)",
-                    [
-                        (
-                            "::TestConstructorOverloads::constructor::foo",
-                            "foo",
-                            "Object",
-                            False,
-                            False,
-                        )
-                    ],
-                ),
-                (
-                    "TestConstructorOverloads (Wrapper)",
-                    [
-                        (
-                            "::TestConstructorOverloads::constructor::bar",
-                            "bar",
-                            "Boolean",
-                            False,
-                            False,
-                        )
-                    ],
-                ),
-            ],
-        )
-        harness.check(
-            len(results[2].members),
-            0,
-            "TestConstructorOverloads should not have members",
-        )
-
-    parser.parse(
-        """
-        interface TestConstructorNoArgs {
-          constructor();
-        };
-
-        interface TestConstructorWithArgs {
-          constructor(DOMString name);
-        };
-
-        interface TestConstructorOverloads {
-          constructor(object foo);
-          constructor(boolean bar);
-        };
-    """
-    )
-    results = parser.finish()
-    checkResults(results)
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestPrefConstructor {
-            [Pref="dom.webidl.test1"] constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestPrefConstructor::constructor",
-        "constructor",
-        [("TestPrefConstructor (Wrapper)", [])],
-        pref=["dom.webidl.test1"],
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestChromeOnlyConstructor {
-          [ChromeOnly] constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestChromeOnlyConstructor::constructor",
-        "constructor",
-        [("TestChromeOnlyConstructor (Wrapper)", [])],
-        chromeOnly=True,
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestSCConstructor {
-            [SecureContext] constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestSCConstructor::constructor",
-        "constructor",
-        [("TestSCConstructor (Wrapper)", [])],
-        secureContext=True,
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestFuncConstructor {
-            [Func="Document::IsWebAnimationsEnabled"] constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestFuncConstructor::constructor",
-        "constructor",
-        [("TestFuncConstructor (Wrapper)", [])],
-        func=["Document::IsWebAnimationsEnabled"],
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestPrefChromeOnlySCFuncConstructor {
-            [ChromeOnly, Pref="dom.webidl.test1", SecureContext, Func="Document::IsWebAnimationsEnabled"]
-            constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestPrefChromeOnlySCFuncConstructor::constructor",
-        "constructor",
-        [("TestPrefChromeOnlySCFuncConstructor (Wrapper)", [])],
-        func=["Document::IsWebAnimationsEnabled"],
-        pref=["dom.webidl.test1"],
-        chromeOnly=True,
-        secureContext=True,
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestHTMLConstructor {
-          [HTMLConstructor] constructor();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    checkMethod(
-        results[0].ctor(),
-        "::TestHTMLConstructor::constructor",
-        "constructor",
-        [("TestHTMLConstructor (Wrapper)", [])],
-        htmlConstructor=True,
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-        interface TestChromeOnlyConstructor {
-          constructor()
-          [ChromeOnly] constructor(DOMString a);
-        };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have both a constructor and a ChromeOnly constructor")
-
-    # Test HTMLConstructor with argument
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorWithArgs {
-              [HTMLConstructor] constructor(DOMString a);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "HTMLConstructor should take no argument")
-
-    # Test HTMLConstructor on a callback interface
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            callback interface TestHTMLConstructorOnCallbackInterface {
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "HTMLConstructor can't be used on a callback interface")
-
-    # Test HTMLConstructor and constructor operation
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              constructor();
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have both a constructor and a HTMLConstructor")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [Throws]
-              constructor();
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have both a throwing constructor and a HTMLConstructor")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              constructor(DOMString a);
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have both a HTMLConstructor and a constructor operation")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [Throws]
-              constructor(DOMString a);
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Can't have both a HTMLConstructor and a throwing constructor " "operation",
-    )
-
-    # Test HTMLConstructor and [ChromeOnly] constructor operation
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [ChromeOnly]
-              constructor();
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have both a ChromeOnly constructor and a HTMLConstructor")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [Throws, ChromeOnly]
-              constructor();
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Can't have both a throwing chromeonly constructor and a " "HTMLConstructor",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [ChromeOnly]
-              constructor(DOMString a);
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Can't have both a HTMLConstructor and a chromeonly constructor " "operation",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestHTMLConstructorAndConstructor {
-              [Throws, ChromeOnly]
-              constructor(DOMString a);
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Can't have both a HTMLConstructor and a throwing chromeonly "
-        "constructor operation",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyNoInterfaceObject]
-            interface InterfaceWithoutInterfaceObject {
-              constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Can't have a constructor operation on a [LegacyNoInterfaceObject] "
-        "interface",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface InterfaceWithPartial {
-            };
-
-            partial interface InterfaceWithPartial {
-              constructor();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have a constructor operation on a partial interface")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface InterfaceWithMixin {
-            };
-
-            interface mixin Mixin {
-              constructor();
-            };
-
-            InterfaceWithMixin includes Mixin
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Can't have a constructor operation on a mixin")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_constructor_global.py b/components/script/dom/bindings/codegen/parser/tests/test_constructor_global.py
deleted file mode 100644
index 5f3663602e4..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_constructor_global.py
+++ /dev/null
@@ -1,72 +0,0 @@
-import traceback
-
-
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=TestConstructorGlobal]
-            interface TestConstructorGlobal {
-              constructor();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=TestLegacyFactoryFunctionGlobal,
-             LegacyFactoryFunction=FooBar]
-            interface TestLegacyFactoryFunctionGlobal {
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyFactoryFunction=FooBar, Global,
-             Exposed=TestLegacyFactoryFunctionGlobal]
-            interface TestLegacyFactoryFunctionGlobal {
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=TestHTMLConstructorGlobal]
-            interface TestHTMLConstructorGlobal {
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_constructor_no_interface_object.py b/components/script/dom/bindings/codegen/parser/tests/test_constructor_no_interface_object.py
deleted file mode 100644
index 9855352a9d4..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_constructor_no_interface_object.py
+++ /dev/null
@@ -1,47 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyNoInterfaceObject]
-            interface TestConstructorLegacyNoInterfaceObject {
-              constructor();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-
-    parser.parse(
-        """
-        [LegacyNoInterfaceObject, LegacyFactoryFunction=FooBar]
-        interface TestLegacyFactoryFunctionLegacyNoInterfaceObject {
-        };
-    """
-    )
-
-    # Test HTMLConstructor and LegacyNoInterfaceObject
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyNoInterfaceObject]
-            interface TestHTMLConstructorLegacyNoInterfaceObject {
-              [HTMLConstructor] constructor();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_deduplicate.py b/components/script/dom/bindings/codegen/parser/tests/test_deduplicate.py
deleted file mode 100644
index 6649f4ec05d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_deduplicate.py
+++ /dev/null
@@ -1,20 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface Foo;
-        interface Bar;
-        interface Foo;
-        """
-    )
-
-    results = parser.finish()
-
-    # There should be no duplicate interfaces in the result.
-    expectedNames = sorted(["Foo", "Bar"])
-    actualNames = sorted(map(lambda iface: iface.identifier.name, results))
-    harness.check(
-        actualNames, expectedNames, "Parser shouldn't output duplicate names."
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_dictionary.py b/components/script/dom/bindings/codegen/parser/tests/test_dictionary.py
deleted file mode 100644
index e7d04f995a9..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_dictionary.py
+++ /dev/null
@@ -1,875 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      dictionary Dict2 : Dict1 {
-        long child = 5;
-        Dict1 aaandAnother;
-      };
-      dictionary Dict1 {
-        long parent;
-        double otherParent;
-      };
-    """
-    )
-    results = parser.finish()
-
-    dict1 = results[1]
-    dict2 = results[0]
-
-    harness.check(len(dict1.members), 2, "Dict1 has two members")
-    harness.check(len(dict2.members), 2, "Dict2 has four members")
-
-    harness.check(
-        dict1.members[0].identifier.name, "otherParent", "'o' comes before 'p'"
-    )
-    harness.check(
-        dict1.members[1].identifier.name, "parent", "'o' really comes before 'p'"
-    )
-    harness.check(
-        dict2.members[0].identifier.name, "aaandAnother", "'a' comes before 'c'"
-    )
-    harness.check(
-        dict2.members[1].identifier.name, "child", "'a' really comes before 'c'"
-    )
-
-    # Test partial dictionary.
-    parser = parser.reset()
-    parser.parse(
-        """
-      dictionary A {
-        long c;
-        long g;
-      };
-      partial dictionary A {
-        long h;
-        long d;
-      };
-    """
-    )
-    results = parser.finish()
-
-    dict1 = results[0]
-    harness.check(len(dict1.members), 4, "Dict1 has four members")
-    harness.check(dict1.members[0].identifier.name, "c", "c should be first")
-    harness.check(dict1.members[1].identifier.name, "d", "d should come after c")
-    harness.check(dict1.members[2].identifier.name, "g", "g should come after d")
-    harness.check(dict1.members[3].identifier.name, "h", "h should be last")
-
-    # Now reset our parser
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          dictionary Dict {
-            long prop = 5;
-            long prop;
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow name duplication in a dictionary")
-
-    # Test no name duplication across normal and partial dictionary.
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          dictionary A {
-            long prop = 5;
-          };
-          partial dictionary A {
-            long prop;
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not allow name duplication across normal and partial dictionary"
-    )
-
-    # Now reset our parser again
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          dictionary Dict1 : Dict2 {
-            long prop = 5;
-          };
-          dictionary Dict2 : Dict3 {
-            long prop2;
-          };
-          dictionary Dict3 {
-            double prop;
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not allow name duplication in a dictionary and " "its ancestor"
-    )
-
-    # More reset
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Iface {};
-          dictionary Dict : Iface {
-            long prop;
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow non-dictionary parents for dictionaries")
-
-    # Even more reset
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A : B {};
-            dictionary B : A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow cycles in dictionary inheritance chains")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-              [LegacyNullToEmptyString] DOMString foo;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not allow [LegacyNullToEmptyString] on dictionary members"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(A arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Trailing dictionary arg must be optional")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional A arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Trailing dictionary arg must have a default value")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo((A or DOMString) arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Trailing union arg containing a dictionary must be optional")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional (A or DOMString) arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Trailing union arg containing a dictionary must have a default value"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(A arg1, optional long arg2);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Dictionary arg followed by optional arg must be optional")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional A arg1, optional long arg2);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Dictionary arg followed by optional arg must have default value")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(A arg1, optional long arg2, long arg3);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        not threw,
-        "Dictionary arg followed by non-optional arg doesn't have to be optional",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo((A or DOMString) arg1, optional long arg2);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Union arg containing dictionary followed by optional arg must " "be optional",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional (A or DOMString) arg1, optional long arg2);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Union arg containing dictionary followed by optional arg must "
-        "have a default value",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(A arg1, long arg2);
-            };
-        """
-    )
-    results = parser.finish()
-    harness.ok(True, "Dictionary arg followed by required arg can be required")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional A? arg1 = {});
-            };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = x
-
-    harness.ok(threw, "Optional dictionary arg must not be nullable")
-    harness.ok(
-        "nullable" in str(threw),
-        "Must have the expected exception for optional nullable dictionary arg",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-              required long x;
-            };
-            interface X {
-              undefined doFoo(A? arg1);
-            };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = x
-
-    harness.ok(threw, "Required dictionary arg must not be nullable")
-    harness.ok(
-        "nullable" in str(threw),
-        "Must have the expected exception for required nullable " "dictionary arg",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional (A or long)? arg1 = {});
-            };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = x
-
-    harness.ok(threw, "Dictionary arg must not be in an optional nullable union")
-    harness.ok(
-        "nullable" in str(threw),
-        "Must have the expected exception for optional nullable union "
-        "arg containing dictionary",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-              required long x;
-            };
-            interface X {
-              undefined doFoo((A or long)? arg1);
-            };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = x
-
-    harness.ok(threw, "Dictionary arg must not be in a required nullable union")
-    harness.ok(
-        "nullable" in str(threw),
-        "Must have the expected exception for required nullable union "
-        "arg containing dictionary",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(sequence<A?> arg1);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(not threw, "Nullable union should be allowed in a sequence argument")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional (A or long?) arg1);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Dictionary must not be in a union with a nullable type")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-            };
-            interface X {
-              undefined doFoo(optional (long? or A) arg1);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "A nullable type must not be in a union with a dictionary")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary A {
-        };
-        interface X {
-          A? doFoo();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(True, "Dictionary return value can be nullable")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary A {
-        };
-        interface X {
-          undefined doFoo(optional A arg = {});
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(True, "Dictionary arg should actually parse")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary A {
-        };
-        interface X {
-          undefined doFoo(optional (A or DOMString) arg = {});
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(True, "Union arg containing a dictionary should actually parse")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary A {
-        };
-        interface X {
-          undefined doFoo(optional (A or DOMString) arg = "abc");
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(
-        True,
-        "Union arg containing a dictionary with string default should actually parse",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              Foo foo;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Member type must not be its Dictionary.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo3 : Foo {
-              short d;
-            };
-
-            dictionary Foo2 : Foo3 {
-              boolean c;
-            };
-
-            dictionary Foo1 : Foo2 {
-              long a;
-            };
-
-            dictionary Foo {
-              Foo1 b;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be a Dictionary that " "inherits from its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              (Foo or DOMString)[]? b;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be a Nullable type "
-        "whose inner type includes its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              (DOMString or Foo) b;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be a Union type, one of "
-        "whose member types includes its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              sequence<sequence<sequence<Foo>>> c;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be a Sequence type "
-        "whose element type includes its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              (DOMString or Foo)[] d;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be an Array type "
-        "whose element type includes its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              Foo1 b;
-            };
-
-            dictionary Foo3 {
-              Foo d;
-            };
-
-            dictionary Foo2 : Foo3 {
-              short c;
-            };
-
-            dictionary Foo1 : Foo2 {
-              long a;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Member type must not be a Dictionary, one of whose "
-        "members or inherited members has a type that includes "
-        "its Dictionary.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-            };
-
-            dictionary Bar {
-              Foo? d;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Member type must not be a nullable dictionary")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary Foo {
-          unrestricted float  urFloat = 0;
-          unrestricted float  urFloat2 = 1.1;
-          unrestricted float  urFloat3 = -1.1;
-          unrestricted float? urFloat4 = null;
-          unrestricted float  infUrFloat = Infinity;
-          unrestricted float  negativeInfUrFloat = -Infinity;
-          unrestricted float  nanUrFloat = NaN;
-
-          unrestricted double  urDouble = 0;
-          unrestricted double  urDouble2 = 1.1;
-          unrestricted double  urDouble3 = -1.1;
-          unrestricted double? urDouble4 = null;
-          unrestricted double  infUrDouble = Infinity;
-          unrestricted double  negativeInfUrDouble = -Infinity;
-          unrestricted double  nanUrDouble = NaN;
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(True, "Parsing default values for unrestricted types succeeded.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              double f = Infinity;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to Infinity")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              double f = -Infinity;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to -Infinity")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              double f = NaN;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to NaN")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              float f = Infinity;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to Infinity")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              float f = -Infinity;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to -Infinity")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              float f = NaN;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Only unrestricted values can be initialized to NaN")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Foo {
-              long module;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(not threw, "Should be able to use 'module' as a dictionary member name")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_distinguishability.py b/components/script/dom/bindings/codegen/parser/tests/test_distinguishability.py
deleted file mode 100644
index e96026c2a09..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_distinguishability.py
+++ /dev/null
@@ -1,425 +0,0 @@
-import traceback
-
-
-def firstArgType(method):
-    return method.signatures()[0][1][0].type
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      // Give our dictionary a required member so we don't need to
-      // mess with optional and default values.
-      dictionary Dict {
-        required long member;
-      };
-      callback interface Foo {
-      };
-      interface Bar {
-        // Bit of a pain to get things that have dictionary types
-        undefined passDict(Dict arg);
-        undefined passFoo(Foo arg);
-        undefined passNullableUnion((object? or DOMString) arg);
-        undefined passNullable(Foo? arg);
-      };
-    """
-    )
-    results = parser.finish()
-
-    iface = results[2]
-    harness.ok(iface.isInterface(), "Should have interface")
-    dictMethod = iface.members[0]
-    ifaceMethod = iface.members[1]
-    nullableUnionMethod = iface.members[2]
-    nullableIfaceMethod = iface.members[3]
-
-    dictType = firstArgType(dictMethod)
-    ifaceType = firstArgType(ifaceMethod)
-
-    harness.ok(dictType.isDictionary(), "Should have dictionary type")
-    harness.ok(ifaceType.isInterface(), "Should have interface type")
-    harness.ok(ifaceType.isCallbackInterface(), "Should have callback interface type")
-
-    harness.ok(
-        not dictType.isDistinguishableFrom(ifaceType),
-        "Dictionary not distinguishable from callback interface",
-    )
-    harness.ok(
-        not ifaceType.isDistinguishableFrom(dictType),
-        "Callback interface not distinguishable from dictionary",
-    )
-
-    nullableUnionType = firstArgType(nullableUnionMethod)
-    nullableIfaceType = firstArgType(nullableIfaceMethod)
-
-    harness.ok(nullableUnionType.isUnion(), "Should have union type")
-    harness.ok(nullableIfaceType.isInterface(), "Should have interface type")
-    harness.ok(nullableIfaceType.nullable(), "Should have nullable type")
-
-    harness.ok(
-        not nullableUnionType.isDistinguishableFrom(nullableIfaceType),
-        "Nullable type not distinguishable from union with nullable " "member type",
-    )
-    harness.ok(
-        not nullableIfaceType.isDistinguishableFrom(nullableUnionType),
-        "Union with nullable member type not distinguishable from " "nullable type",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      interface TestIface {
-        undefined passKid(Kid arg);
-        undefined passParent(Parent arg);
-        undefined passGrandparent(Grandparent arg);
-        undefined passUnrelated1(Unrelated1 arg);
-        undefined passUnrelated2(Unrelated2 arg);
-        undefined passArrayBuffer(ArrayBuffer arg);
-        undefined passArrayBuffer(ArrayBufferView arg);
-      };
-
-      interface Kid : Parent {};
-      interface Parent : Grandparent {};
-      interface Grandparent {};
-      interface Unrelated1 {};
-      interface Unrelated2 {};
-    """
-    )
-    results = parser.finish()
-
-    iface = results[0]
-    harness.ok(iface.isInterface(), "Should have interface")
-    argTypes = [firstArgType(method) for method in iface.members]
-    unrelatedTypes = [firstArgType(method) for method in iface.members[-3:]]
-
-    for type1 in argTypes:
-        for type2 in argTypes:
-            distinguishable = type1 is not type2 and (
-                type1 in unrelatedTypes or type2 in unrelatedTypes
-            )
-
-            harness.check(
-                type1.isDistinguishableFrom(type2),
-                distinguishable,
-                "Type %s should %sbe distinguishable from type %s"
-                % (type1, "" if distinguishable else "not ", type2),
-            )
-            harness.check(
-                type2.isDistinguishableFrom(type1),
-                distinguishable,
-                "Type %s should %sbe distinguishable from type %s"
-                % (type2, "" if distinguishable else "not ", type1),
-            )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      interface Dummy {};
-      interface TestIface {
-        undefined method(long arg1, TestIface arg2);
-        undefined method(long arg1, long arg2);
-        undefined method(long arg1, Dummy arg2);
-        undefined method(DOMString arg1, DOMString arg2, DOMString arg3);
-      };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results[1].members), 1, "Should look like we have one method")
-    harness.check(
-        len(results[1].members[0].signatures()), 4, "Should have four signatures"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Dummy {};
-          interface TestIface {
-            undefined method(long arg1, TestIface arg2);
-            undefined method(long arg1, long arg2);
-            undefined method(any arg1,  Dummy arg2);
-            undefined method(DOMString arg1, DOMString arg2, DOMString arg3);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should throw when args before the distinguishing arg are not "
-        "all the same type",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Dummy {};
-          interface TestIface {
-            undefined method(long arg1, TestIface arg2);
-            undefined method(long arg1, long arg2);
-            undefined method(any arg1,  DOMString arg2);
-            undefined method(DOMString arg1, DOMString arg2, DOMString arg3);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should throw when there is no distinguishing index")
-
-    # Now let's test our whole distinguishability table
-    argTypes = [
-        "long",
-        "short",
-        "long?",
-        "short?",
-        "boolean",
-        "boolean?",
-        "undefined",
-        "undefined?",
-        "DOMString",
-        "ByteString",
-        "UTF8String",
-        "Enum",
-        "Enum2",
-        "Interface",
-        "Interface?",
-        "AncestorInterface",
-        "UnrelatedInterface",
-        "CallbackInterface",
-        "CallbackInterface?",
-        "CallbackInterface2",
-        "object",
-        "Callback",
-        "Callback2",
-        "Dict",
-        "Dict2",
-        "sequence<long>",
-        "sequence<short>",
-        "record<DOMString, object>",
-        "record<USVString, Dict>",
-        "record<ByteString, long>",
-        "record<UTF8String, long>",
-        "any",
-        "Promise<any>",
-        "Promise<any>?",
-        "USVString",
-        "JSString",
-        "ArrayBuffer",
-        "ArrayBufferView",
-        "Uint8Array",
-        "Uint16Array",
-        "(long or Callback)",
-        "(long or Dict)",
-    ]
-
-    # Try to categorize things a bit to keep list lengths down
-    def allBut(list1, list2):
-        return [
-            a
-            for a in list1
-            if a not in list2
-            and (a != "any" and a != "Promise<any>" and a != "Promise<any>?")
-        ]
-
-    unions = ["(long or Callback)", "(long or Dict)"]
-    numerics = ["long", "short", "long?", "short?"]
-    booleans = ["boolean", "boolean?"]
-    undefineds = ["undefined", "undefined?"]
-    primitives = numerics + booleans
-    nonNumerics = allBut(argTypes, numerics + unions)
-    nonBooleans = allBut(argTypes, booleans)
-    strings = [
-        "DOMString",
-        "ByteString",
-        "Enum",
-        "Enum2",
-        "USVString",
-        "JSString",
-        "UTF8String",
-    ]
-    nonStrings = allBut(argTypes, strings)
-    nonObjects = undefineds + primitives + strings
-    objects = allBut(argTypes, nonObjects)
-    bufferSourceTypes = ["ArrayBuffer", "ArrayBufferView", "Uint8Array", "Uint16Array"]
-    interfaces = [
-        "Interface",
-        "Interface?",
-        "AncestorInterface",
-        "UnrelatedInterface",
-    ] + bufferSourceTypes
-    nullables = [
-        "long?",
-        "short?",
-        "boolean?",
-        "undefined?",
-        "Interface?",
-        "CallbackInterface?",
-        "Dict",
-        "Dict2",
-        "Date?",
-        "any",
-        "Promise<any>?",
-    ] + allBut(unions, ["(long or Callback)"])
-    sequences = ["sequence<long>", "sequence<short>"]
-    nonUserObjects = nonObjects + interfaces + sequences
-    otherObjects = allBut(argTypes, nonUserObjects + ["object"])
-    notRelatedInterfaces = (
-        nonObjects
-        + ["UnrelatedInterface"]
-        + otherObjects
-        + sequences
-        + bufferSourceTypes
-    )
-    records = [
-        "record<DOMString, object>",
-        "record<USVString, Dict>",
-        "record<ByteString, long>",
-        "record<UTF8String, long>",
-    ]  # JSString not supported in records
-    dictionaryLike = (
-        [
-            "Dict",
-            "Dict2",
-            "CallbackInterface",
-            "CallbackInterface?",
-            "CallbackInterface2",
-        ]
-        + records
-        + allBut(unions, ["(long or Callback)"])
-    )
-
-    # Build a representation of the distinguishability table as a dict
-    # of dicts, holding True values where needed, holes elsewhere.
-    data = dict()
-    for type in argTypes:
-        data[type] = dict()
-
-    def setDistinguishable(type, types):
-        for other in types:
-            data[type][other] = True
-
-    setDistinguishable("long", nonNumerics)
-    setDistinguishable("short", nonNumerics)
-    setDistinguishable("long?", allBut(nonNumerics, nullables))
-    setDistinguishable("short?", allBut(nonNumerics, nullables))
-    setDistinguishable("boolean", nonBooleans)
-    setDistinguishable("boolean?", allBut(nonBooleans, nullables))
-    setDistinguishable("undefined", allBut(argTypes, undefineds + dictionaryLike))
-    setDistinguishable(
-        "undefined?", allBut(argTypes, undefineds + dictionaryLike + nullables)
-    )
-    setDistinguishable("DOMString", nonStrings)
-    setDistinguishable("ByteString", nonStrings)
-    setDistinguishable("UTF8String", nonStrings)
-    setDistinguishable("USVString", nonStrings)
-    setDistinguishable("JSString", nonStrings)
-    setDistinguishable("Enum", nonStrings)
-    setDistinguishable("Enum2", nonStrings)
-    setDistinguishable("Interface", notRelatedInterfaces)
-    setDistinguishable("Interface?", allBut(notRelatedInterfaces, nullables))
-    setDistinguishable("AncestorInterface", notRelatedInterfaces)
-    setDistinguishable(
-        "UnrelatedInterface", allBut(argTypes, ["object", "UnrelatedInterface"])
-    )
-    setDistinguishable("CallbackInterface", allBut(nonUserObjects, undefineds))
-    setDistinguishable(
-        "CallbackInterface?", allBut(nonUserObjects, nullables + undefineds)
-    )
-    setDistinguishable("CallbackInterface2", allBut(nonUserObjects, undefineds))
-    setDistinguishable("object", nonObjects)
-    setDistinguishable("Callback", nonUserObjects)
-    setDistinguishable("Callback2", nonUserObjects)
-    setDistinguishable("Dict", allBut(nonUserObjects, nullables + undefineds))
-    setDistinguishable("Dict2", allBut(nonUserObjects, nullables + undefineds))
-    setDistinguishable("sequence<long>", allBut(argTypes, sequences + ["object"]))
-    setDistinguishable("sequence<short>", allBut(argTypes, sequences + ["object"]))
-    setDistinguishable("record<DOMString, object>", allBut(nonUserObjects, undefineds))
-    setDistinguishable("record<USVString, Dict>", allBut(nonUserObjects, undefineds))
-    # JSString not supported in records
-    setDistinguishable("record<ByteString, long>", allBut(nonUserObjects, undefineds))
-    setDistinguishable("record<UTF8String, long>", allBut(nonUserObjects, undefineds))
-    setDistinguishable("any", [])
-    setDistinguishable("Promise<any>", [])
-    setDistinguishable("Promise<any>?", [])
-    setDistinguishable("ArrayBuffer", allBut(argTypes, ["ArrayBuffer", "object"]))
-    setDistinguishable(
-        "ArrayBufferView",
-        allBut(argTypes, ["ArrayBufferView", "Uint8Array", "Uint16Array", "object"]),
-    )
-    setDistinguishable(
-        "Uint8Array", allBut(argTypes, ["ArrayBufferView", "Uint8Array", "object"])
-    )
-    setDistinguishable(
-        "Uint16Array", allBut(argTypes, ["ArrayBufferView", "Uint16Array", "object"])
-    )
-    setDistinguishable("(long or Callback)", allBut(nonUserObjects, numerics))
-    setDistinguishable(
-        "(long or Dict)", allBut(nonUserObjects, numerics + nullables + undefineds)
-    )
-
-    def areDistinguishable(type1, type2):
-        return data[type1].get(type2, False)
-
-    def checkDistinguishability(parser, type1, type2):
-        idlTemplate = """
-          enum Enum { "a", "b" };
-          enum Enum2 { "c", "d" };
-          interface Interface : AncestorInterface {};
-          interface AncestorInterface {};
-          interface UnrelatedInterface {};
-          callback interface CallbackInterface {};
-          callback interface CallbackInterface2 {};
-          callback Callback = any();
-          callback Callback2 = long(short arg);
-          // Give our dictionaries required members so we don't need to
-          // mess with optional and default values.
-          dictionary Dict { required long member; };
-          dictionary Dict2 { required long member; };
-          interface TestInterface {%s
-          };
-        """
-        if type1 in undefineds or type2 in undefineds:
-            methods = """
-                (%s or %s) myMethod();""" % (
-                type1,
-                type2,
-            )
-        else:
-            methodTemplate = """
-                undefined myMethod(%s arg);"""
-            methods = (methodTemplate % type1) + (methodTemplate % type2)
-        idl = idlTemplate % methods
-
-        parser = parser.reset()
-        threw = False
-        try:
-            parser.parse(idl)
-            results = parser.finish()
-        except:
-            threw = True
-
-        if areDistinguishable(type1, type2):
-            harness.ok(
-                not threw,
-                "Should not throw for '%s' and '%s' because they are distinguishable"
-                % (type1, type2),
-            )
-        else:
-            harness.ok(
-                threw,
-                "Should throw for '%s' and '%s' because they are not distinguishable"
-                % (type1, type2),
-            )
-
-    # Enumerate over everything in both orders, since order matters in
-    # terms of our implementation of distinguishability checks
-    for type1 in argTypes:
-        for type2 in argTypes:
-            checkDistinguishability(parser, type1, type2)
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_double_null.py b/components/script/dom/bindings/codegen/parser/tests/test_double_null.py
deleted file mode 100644
index a8876a7fd2d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_double_null.py
+++ /dev/null
@@ -1,16 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DoubleNull {
-              attribute byte?? foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_duplicate_qualifiers.py b/components/script/dom/bindings/codegen/parser/tests/test_duplicate_qualifiers.py
deleted file mode 100644
index 89a4e1acf0b..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_duplicate_qualifiers.py
+++ /dev/null
@@ -1,64 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DuplicateQualifiers1 {
-              getter getter byte foo(unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DuplicateQualifiers2 {
-              setter setter byte foo(unsigned long index, byte value);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DuplicateQualifiers4 {
-              deleter deleter byte foo(unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface DuplicateQualifiers5 {
-              getter deleter getter byte foo(unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_empty_enum.py b/components/script/dom/bindings/codegen/parser/tests/test_empty_enum.py
deleted file mode 100644
index 09333a659cd..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_empty_enum.py
+++ /dev/null
@@ -1,17 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    try:
-        parser.parse(
-            """
-            enum TestEmptyEnum {
-            };
-        """
-        )
-
-        harness.ok(False, "Should have thrown!")
-    except:
-        harness.ok(True, "Parsing TestEmptyEnum enum should fail")
-
-    results = parser.finish()
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_empty_sequence_default_value.py b/components/script/dom/bindings/codegen/parser/tests/test_empty_sequence_default_value.py
deleted file mode 100644
index 21837743523..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_empty_sequence_default_value.py
+++ /dev/null
@@ -1,54 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface X {
-              const sequence<long> foo = [];
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Constant cannot have [] as a default value")
-
-    parser = parser.reset()
-
-    parser.parse(
-        """
-        interface X {
-          undefined foo(optional sequence<long> arg = []);
-        };
-    """
-    )
-    results = parser.finish()
-
-    harness.ok(
-        isinstance(
-            results[0].members[0].signatures()[0][1][0].defaultValue,
-            WebIDL.IDLEmptySequenceValue,
-        ),
-        "Should have IDLEmptySequenceValue as default value of argument",
-    )
-
-    parser = parser.reset()
-
-    parser.parse(
-        """
-        dictionary X {
-          sequence<long> foo = [];
-        };
-    """
-    )
-    results = parser.finish()
-
-    harness.ok(
-        isinstance(results[0].members[0].defaultValue, WebIDL.IDLEmptySequenceValue),
-        "Should have IDLEmptySequenceValue as default value of " "dictionary member",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_enum.py b/components/script/dom/bindings/codegen/parser/tests/test_enum.py
deleted file mode 100644
index 56c6b3f64aa..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_enum.py
+++ /dev/null
@@ -1,107 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        enum TestEnum {
-          "",
-          "foo",
-          "bar"
-        };
-
-        interface TestEnumInterface {
-          TestEnum doFoo(boolean arg);
-          readonly attribute TestEnum foo;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestEnumInterfaces interface parsed without error.")
-    harness.check(len(results), 2, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLEnum), "Should be an IDLEnum")
-    harness.ok(isinstance(results[1], WebIDL.IDLInterface), "Should be an IDLInterface")
-
-    enum = results[0]
-    harness.check(enum.identifier.QName(), "::TestEnum", "Enum has the right QName")
-    harness.check(enum.identifier.name, "TestEnum", "Enum has the right name")
-    harness.check(enum.values(), ["", "foo", "bar"], "Enum has the right values")
-
-    iface = results[1]
-
-    harness.check(
-        iface.identifier.QName(), "::TestEnumInterface", "Interface has the right QName"
-    )
-    harness.check(
-        iface.identifier.name, "TestEnumInterface", "Interface has the right name"
-    )
-    harness.check(iface.parent, None, "Interface has no parent")
-
-    members = iface.members
-    harness.check(len(members), 2, "Should be one production")
-    harness.ok(isinstance(members[0], WebIDL.IDLMethod), "Should be an IDLMethod")
-    method = members[0]
-    harness.check(
-        method.identifier.QName(),
-        "::TestEnumInterface::doFoo",
-        "Method has correct QName",
-    )
-    harness.check(method.identifier.name, "doFoo", "Method has correct name")
-
-    signatures = method.signatures()
-    harness.check(len(signatures), 1, "Expect one signature")
-
-    (returnType, arguments) = signatures[0]
-    harness.check(
-        str(returnType), "TestEnum (Wrapper)", "Method type is the correct name"
-    )
-    harness.check(len(arguments), 1, "Method has the right number of arguments")
-    arg = arguments[0]
-    harness.ok(isinstance(arg, WebIDL.IDLArgument), "Should be an IDLArgument")
-    harness.check(str(arg.type), "Boolean", "Argument has the right type")
-
-    attr = members[1]
-    harness.check(
-        attr.identifier.QName(), "::TestEnumInterface::foo", "Attr has correct QName"
-    )
-    harness.check(attr.identifier.name, "foo", "Attr has correct name")
-
-    harness.check(str(attr.type), "TestEnum (Wrapper)", "Attr type is the correct name")
-
-    # Now reset our parser
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          enum Enum {
-            "a",
-            "b",
-            "c"
-          };
-          interface TestInterface {
-            undefined foo(optional Enum e = "d");
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow a bogus default value for an enum")
-
-    # Now reset our parser
-    parser = parser.reset()
-    parser.parse(
-        """
-      enum Enum {
-        "a",
-        "b",
-        "c",
-      };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should allow trailing comma in enum")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_enum_duplicate_values.py b/components/script/dom/bindings/codegen/parser/tests/test_enum_duplicate_values.py
deleted file mode 100644
index 8969281e1c7..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_enum_duplicate_values.py
+++ /dev/null
@@ -1,16 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    try:
-        parser.parse(
-            """
-            enum TestEnumDuplicateValue {
-              "",
-              ""
-            };
-        """
-        )
-        harness.ok(False, "Should have thrown!")
-    except:
-        harness.ok(True, "Enum TestEnumDuplicateValue should throw")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_error_colno.py b/components/script/dom/bindings/codegen/parser/tests/test_error_colno.py
deleted file mode 100644
index 1c9bb065580..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_error_colno.py
+++ /dev/null
@@ -1,24 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    # Check that error messages put the '^' in the right place.
-
-    threw = False
-    input = "interface ?"
-    try:
-        parser.parse(input)
-        results = parser.finish()
-    except WebIDL.WebIDLError as e:
-        threw = True
-        lines = str(e).split("\n")
-
-        harness.check(len(lines), 3, "Expected number of lines in error message")
-        harness.check(lines[1], input, "Second line shows error")
-        harness.check(
-            lines[2],
-            " " * (len(input) - 1) + "^",
-            "Correct column pointer in error message",
-        )
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_error_lineno.py b/components/script/dom/bindings/codegen/parser/tests/test_error_lineno.py
deleted file mode 100644
index 0d10e006787..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_error_lineno.py
+++ /dev/null
@@ -1,38 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    # Check that error messages put the '^' in the right place.
-
-    threw = False
-    input = """\
-// This is a comment.
-interface Foo {
-};
-
-/* This is also a comment. */
-interface ?"""
-    try:
-        parser.parse(input)
-        results = parser.finish()
-    except WebIDL.WebIDLError as e:
-        threw = True
-        lines = str(e).split("\n")
-
-        harness.check(len(lines), 3, "Expected number of lines in error message")
-        harness.ok(
-            lines[0].endswith("line 6:10"),
-            'First line of error should end with "line 6:10", but was "%s".' % lines[0],
-        )
-        harness.check(
-            lines[1],
-            "interface ?",
-            "Second line of error message is the line which caused the error.",
-        )
-        harness.check(
-            lines[2],
-            " " * (len("interface ?") - 1) + "^",
-            "Correct column pointer in error message.",
-        )
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_exposed_extended_attribute.py b/components/script/dom/bindings/codegen/parser/tests/test_exposed_extended_attribute.py
deleted file mode 100644
index c5ea8e4b88b..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_exposed_extended_attribute.py
+++ /dev/null
@@ -1,383 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      [Global, Exposed=Foo] interface Foo {};
-      [Global=(Bar, Bar1,Bar2), Exposed=Bar] interface Bar {};
-      [Global=(Baz, Baz2), Exposed=Baz] interface Baz {};
-
-      [Exposed=(Foo,Bar1)]
-      interface Iface {
-        undefined method1();
-
-        [Exposed=Bar1]
-        readonly attribute any attr;
-      };
-
-      [Exposed=Foo]
-      partial interface Iface {
-        undefined method2();
-      };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 5, "Should know about five things")
-    iface = results[3]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should have an interface here")
-    members = iface.members
-    harness.check(len(members), 3, "Should have three members")
-
-    harness.ok(
-        members[0].exposureSet == set(["Foo", "Bar"]),
-        "method1 should have the right exposure set",
-    )
-    harness.ok(
-        members[0]._exposureGlobalNames == set(["Foo", "Bar1"]),
-        "method1 should have the right exposure global names",
-    )
-
-    harness.ok(
-        members[1].exposureSet == set(["Bar"]),
-        "attr should have the right exposure set",
-    )
-    harness.ok(
-        members[1]._exposureGlobalNames == set(["Bar1"]),
-        "attr should have the right exposure global names",
-    )
-
-    harness.ok(
-        members[2].exposureSet == set(["Foo"]),
-        "method2 should have the right exposure set",
-    )
-    harness.ok(
-        members[2]._exposureGlobalNames == set(["Foo"]),
-        "method2 should have the right exposure global names",
-    )
-
-    harness.ok(
-        iface.exposureSet == set(["Foo", "Bar"]),
-        "Iface should have the right exposure set",
-    )
-    harness.ok(
-        iface._exposureGlobalNames == set(["Foo", "Bar1"]),
-        "Iface should have the right exposure global names",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      [Global, Exposed=Foo] interface Foo {};
-      [Global=(Bar, Bar1, Bar2), Exposed=Bar] interface Bar {};
-      [Global=(Baz, Baz2), Exposed=Baz] interface Baz {};
-
-      [Exposed=Foo]
-      interface Iface2 {
-        undefined method3();
-      };
-    """
-    )
-    results = parser.finish()
-
-    harness.check(len(results), 4, "Should know about four things")
-    iface = results[3]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should have an interface here")
-    members = iface.members
-    harness.check(len(members), 1, "Should have one member")
-
-    harness.ok(
-        members[0].exposureSet == set(["Foo"]),
-        "method3 should have the right exposure set",
-    )
-    harness.ok(
-        members[0]._exposureGlobalNames == set(["Foo"]),
-        "method3 should have the right exposure global names",
-    )
-
-    harness.ok(
-        iface.exposureSet == set(["Foo"]), "Iface2 should have the right exposure set"
-    )
-    harness.ok(
-        iface._exposureGlobalNames == set(["Foo"]),
-        "Iface2 should have the right exposure global names",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      [Global, Exposed=Foo] interface Foo {};
-      [Global=(Bar, Bar1, Bar2), Exposed=Bar] interface Bar {};
-      [Global=(Baz, Baz2), Exposed=Baz] interface Baz {};
-
-      [Exposed=Foo]
-      interface Iface3 {
-        undefined method4();
-      };
-
-      [Exposed=(Foo,Bar1)]
-      interface mixin Mixin {
-        undefined method5();
-      };
-
-      Iface3 includes Mixin;
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 6, "Should know about six things")
-    iface = results[3]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should have an interface here")
-    members = iface.members
-    harness.check(len(members), 2, "Should have two members")
-
-    harness.ok(
-        members[0].exposureSet == set(["Foo"]),
-        "method4 should have the right exposure set",
-    )
-    harness.ok(
-        members[0]._exposureGlobalNames == set(["Foo"]),
-        "method4 should have the right exposure global names",
-    )
-
-    harness.ok(
-        members[1].exposureSet == set(["Foo", "Bar"]),
-        "method5 should have the right exposure set",
-    )
-    harness.ok(
-        members[1]._exposureGlobalNames == set(["Foo", "Bar1"]),
-        "method5 should have the right exposure global names",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Exposed=Foo]
-            interface Bar {
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on invalid Exposed value on interface.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Bar {
-              [Exposed=Foo]
-              readonly attribute bool attr;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on invalid Exposed value on attribute.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Bar {
-              [Exposed=Foo]
-              undefined operation();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on invalid Exposed value on operation.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Bar {
-              [Exposed=Foo]
-              const long constant = 5;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on invalid Exposed value on constant.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Foo] interface Foo {};
-            [Global, Exposed=Bar] interface Bar {};
-
-            [Exposed=Foo]
-            interface Baz {
-              [Exposed=Bar]
-              undefined method();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(
-        threw, "Should have thrown on member exposed where its interface is not."
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Foo] interface Foo {};
-        [Global, Exposed=Bar] interface Bar {};
-
-        [Exposed=Foo]
-        interface Baz {
-          undefined method();
-        };
-
-        [Exposed=Bar]
-        interface mixin Mixin {
-          undefined otherMethod();
-        };
-
-        Baz includes Mixin;
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 5, "Should know about five things")
-    iface = results[2]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should have an interface here")
-    members = iface.members
-    harness.check(len(members), 2, "Should have two members")
-
-    harness.ok(
-        members[0].exposureSet == set(["Foo"]),
-        "method should have the right exposure set",
-    )
-    harness.ok(
-        members[0]._exposureGlobalNames == set(["Foo"]),
-        "method should have the right exposure global names",
-    )
-
-    harness.ok(
-        members[1].exposureSet == set(["Bar"]),
-        "otherMethod should have the right exposure set",
-    )
-    harness.ok(
-        members[1]._exposureGlobalNames == set(["Bar"]),
-        "otherMethod should have the right exposure global names",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Foo] interface Foo {};
-        [Global, Exposed=Bar] interface Bar {};
-
-        [Exposed=*]
-        interface Baz {
-          undefined methodWild();
-        };
-
-        [Exposed=Bar]
-        interface mixin Mixin {
-          undefined methodNotWild();
-        };
-
-        Baz includes Mixin;
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 5, "Should know about five things")
-    iface = results[2]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should have an interface here")
-    members = iface.members
-    harness.check(len(members), 2, "Should have two members")
-
-    harness.ok(
-        members[0].exposureSet == set(["Foo", "Bar"]),
-        "methodWild should have the right exposure set",
-    )
-    harness.ok(
-        members[0]._exposureGlobalNames == set(["Foo", "Bar"]),
-        "methodWild should have the right exposure global names",
-    )
-
-    harness.ok(
-        members[1].exposureSet == set(["Bar"]),
-        "methodNotWild should have the right exposure set",
-    )
-    harness.ok(
-        members[1]._exposureGlobalNames == set(["Bar"]),
-        "methodNotWild should have the right exposure global names",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Foo] interface Foo {};
-            [Global, Exposed=Bar] interface Bar {};
-
-            [Exposed=Foo]
-            interface Baz {
-              [Exposed=*]
-              undefined method();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(
-        threw, "Should have thrown on member exposed where its interface is not."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Foo] interface Foo {};
-            [Global, Exposed=Bar] interface Bar {};
-
-            [Exposed=(Foo,*)]
-            interface Baz {
-              undefined method();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on a wildcard in an identifier list.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_extended_attributes.py b/components/script/dom/bindings/codegen/parser/tests/test_extended_attributes.py
deleted file mode 100644
index 423a67540c7..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_extended_attributes.py
+++ /dev/null
@@ -1,131 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        [LegacyNoInterfaceObject]
-        interface TestExtendedAttr {
-          [LegacyUnforgeable] readonly attribute byte b;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Pref="foo.bar",Pref=flop]
-        interface TestExtendedAttr {
-          [Pref="foo.bar"] attribute byte b;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestLegacyLenientThis {
-          [LegacyLenientThis] attribute byte b;
-        };
-    """
-    )
-
-    results = parser.finish()
-    harness.ok(
-        results[0].members[0].hasLegacyLenientThis(), "Should have a lenient this"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestLegacyLenientThis2 {
-              [LegacyLenientThis=something] attribute byte b;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "[LegacyLenientThis] must take no arguments")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestClamp {
-          undefined testClamp([Clamp] long foo);
-          undefined testNotClamp(long foo);
-        };
-    """
-    )
-
-    results = parser.finish()
-    # Pull out the first argument out of the arglist of the first (and
-    # only) signature.
-    harness.ok(
-        results[0].members[0].signatures()[0][1][0].type.hasClamp(), "Should be clamped"
-    )
-    harness.ok(
-        not results[0].members[1].signatures()[0][1][0].type.hasClamp(),
-        "Should not be clamped",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestClamp2 {
-              undefined testClamp([Clamp=something] long foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "[Clamp] must take no arguments")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestEnforceRange {
-          undefined testEnforceRange([EnforceRange] long foo);
-          undefined testNotEnforceRange(long foo);
-        };
-    """
-    )
-
-    results = parser.finish()
-    # Pull out the first argument out of the arglist of the first (and
-    # only) signature.
-    harness.ok(
-        results[0].members[0].signatures()[0][1][0].type.hasEnforceRange(),
-        "Should be enforceRange",
-    )
-    harness.ok(
-        not results[0].members[1].signatures()[0][1][0].type.hasEnforceRange(),
-        "Should not be enforceRange",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestEnforceRange2 {
-              undefined testEnforceRange([EnforceRange=something] long foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "[EnforceRange] must take no arguments")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_float_types.py b/components/script/dom/bindings/codegen/parser/tests/test_float_types.py
deleted file mode 100644
index d37443819d8..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_float_types.py
+++ /dev/null
@@ -1,145 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        typedef float myFloat;
-        typedef unrestricted float myUnrestrictedFloat;
-        interface FloatTypes {
-          attribute float f;
-          attribute unrestricted float uf;
-          attribute double d;
-          attribute unrestricted double ud;
-          [LenientFloat]
-          attribute float lf;
-          [LenientFloat]
-          attribute double ld;
-
-          undefined m1(float arg1, double arg2, float? arg3, double? arg4,
-                       myFloat arg5, unrestricted float arg6,
-                       unrestricted double arg7, unrestricted float? arg8,
-                       unrestricted double? arg9, myUnrestrictedFloat arg10);
-          [LenientFloat]
-          undefined m2(float arg1, double arg2, float? arg3, double? arg4,
-                       myFloat arg5, unrestricted float arg6,
-                       unrestricted double arg7, unrestricted float? arg8,
-                       unrestricted double? arg9, myUnrestrictedFloat arg10);
-          [LenientFloat]
-          undefined m3(float arg);
-          [LenientFloat]
-          undefined m4(double arg);
-          [LenientFloat]
-          undefined m5((float or FloatTypes) arg);
-          [LenientFloat]
-          undefined m6(sequence<float> arg);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 3, "Should be two typedefs and one interface.")
-    iface = results[2]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    types = [a.type for a in iface.members if a.isAttr()]
-    harness.ok(types[0].isFloat(), "'float' is a float")
-    harness.ok(not types[0].isUnrestricted(), "'float' is not unrestricted")
-    harness.ok(types[1].isFloat(), "'unrestricted float' is a float")
-    harness.ok(types[1].isUnrestricted(), "'unrestricted float' is unrestricted")
-    harness.ok(types[2].isFloat(), "'double' is a float")
-    harness.ok(not types[2].isUnrestricted(), "'double' is not unrestricted")
-    harness.ok(types[3].isFloat(), "'unrestricted double' is a float")
-    harness.ok(types[3].isUnrestricted(), "'unrestricted double' is unrestricted")
-
-    method = iface.members[6]
-    harness.ok(isinstance(method, WebIDL.IDLMethod), "Should be an IDLMethod")
-    argtypes = [a.type for a in method.signatures()[0][1]]
-    for (idx, type) in enumerate(argtypes):
-        harness.ok(type.isFloat(), "Type %d should be float" % idx)
-        harness.check(
-            type.isUnrestricted(),
-            idx >= 5,
-            "Type %d should %sbe unrestricted" % (idx, "" if idx >= 4 else "not "),
-        )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface FloatTypes {
-              [LenientFloat]
-              long m(float arg);
-            };
-        """
-        )
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "[LenientFloat] only allowed on methods returning undefined")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface FloatTypes {
-              [LenientFloat]
-              undefined m(unrestricted float arg);
-            };
-        """
-        )
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw, "[LenientFloat] only allowed on methods with unrestricted float args"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface FloatTypes {
-              [LenientFloat]
-              undefined m(sequence<unrestricted float> arg);
-            };
-        """
-        )
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw, "[LenientFloat] only allowed on methods with unrestricted float args (2)"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface FloatTypes {
-              [LenientFloat]
-              undefined m((unrestricted float or FloatTypes) arg);
-            };
-        """
-        )
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw, "[LenientFloat] only allowed on methods with unrestricted float args (3)"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface FloatTypes {
-              [LenientFloat]
-              readonly attribute float foo;
-            };
-        """
-        )
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "[LenientFloat] only allowed on writable attributes")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_forward_decl.py b/components/script/dom/bindings/codegen/parser/tests/test_forward_decl.py
deleted file mode 100644
index 1c81718400a..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_forward_decl.py
+++ /dev/null
@@ -1,18 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface ForwardDeclared;
-        interface ForwardDeclared;
-
-        interface TestForwardDecl {
-          attribute ForwardDeclared foo;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestForwardDeclared interface parsed without error.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_global_extended_attr.py b/components/script/dom/bindings/codegen/parser/tests/test_global_extended_attr.py
deleted file mode 100644
index 9ee27efbc8d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_global_extended_attr.py
+++ /dev/null
@@ -1,129 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      [Global, Exposed=Foo]
-      interface Foo : Bar {
-        getter any(DOMString name);
-      };
-      [Exposed=Foo]
-      interface Bar {};
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(
-        results[0].isOnGlobalProtoChain(),
-        "[Global] interface should be on global's proto chain",
-    )
-    harness.ok(
-        results[1].isOnGlobalProtoChain(),
-        "[Global] interface should be on global's proto chain",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          [Global, Exposed=Foo]
-          interface Foo {
-            getter any(DOMString name);
-            setter undefined(DOMString name, any arg);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown for [Global] used on an interface with a " "named setter",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          [Global, Exposed=Foo]
-          interface Foo {
-            getter any(DOMString name);
-            deleter undefined(DOMString name);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown for [Global] used on an interface with a " "named deleter",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          [Global, LegacyOverrideBuiltIns, Exposed=Foo]
-          interface Foo {
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown for [Global] used on an interface with a "
-        "[LegacyOverrideBuiltIns]",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          [Global, Exposed=Foo]
-          interface Foo : Bar {
-          };
-          [LegacyOverrideBuiltIns, Exposed=Foo]
-          interface Bar {
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown for [Global] used on an interface with an "
-        "[LegacyOverrideBuiltIns] ancestor",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          [Global, Exposed=Foo]
-          interface Foo {
-          };
-          [Exposed=Foo]
-          interface Bar : Foo {
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown for [Global] used on an interface with a " "descendant",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_identifier_conflict.py b/components/script/dom/bindings/codegen/parser/tests/test_identifier_conflict.py
deleted file mode 100644
index 7404c86f944..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_identifier_conflict.py
+++ /dev/null
@@ -1,49 +0,0 @@
-# Import the WebIDL module, so we can do isinstance checks and whatnot
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    try:
-        parser.parse(
-            """
-            enum Foo { "a" };
-            interface Foo;
-        """
-        )
-        results = parser.finish()
-        harness.ok(False, "Should fail to parse")
-    except Exception as e:
-        harness.ok(
-            "Name collision" in str(e), "Should have name collision for interface"
-        )
-
-    parser = parser.reset()
-    try:
-        parser.parse(
-            """
-            dictionary Foo { long x; };
-            enum Foo { "a" };
-        """
-        )
-        results = parser.finish()
-        harness.ok(False, "Should fail to parse")
-    except Exception as e:
-        harness.ok(
-            "Name collision" in str(e), "Should have name collision for dictionary"
-        )
-
-    parser = parser.reset()
-    try:
-        parser.parse(
-            """
-            enum Foo { "a" };
-            enum Foo { "b" };
-        """
-        )
-        results = parser.finish()
-        harness.ok(False, "Should fail to parse")
-    except Exception as e:
-        harness.ok(
-            "Multiple unresolvable definitions" in str(e),
-            "Should have name collision for dictionary",
-        )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_incomplete_parent.py b/components/script/dom/bindings/codegen/parser/tests/test_incomplete_parent.py
deleted file mode 100644
index ed476b8ed4c..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_incomplete_parent.py
+++ /dev/null
@@ -1,21 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestIncompleteParent : NotYetDefined {
-          undefined foo();
-        };
-
-        interface NotYetDefined : EvenHigherOnTheChain {
-        };
-
-        interface EvenHigherOnTheChain {
-        };
-    """
-    )
-
-    parser.finish()
-
-    harness.ok(True, "TestIncompleteParent interface parsed without error.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_incomplete_types.py b/components/script/dom/bindings/codegen/parser/tests/test_incomplete_types.py
deleted file mode 100644
index 0d54f708bba..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_incomplete_types.py
+++ /dev/null
@@ -1,61 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestIncompleteTypes {
-          attribute FooInterface attr1;
-
-          FooInterface method1(FooInterface arg);
-        };
-
-        interface FooInterface {
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestIncompleteTypes interface parsed without error.")
-    harness.check(len(results), 2, "Should be two productions.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(),
-        "::TestIncompleteTypes",
-        "Interface has the right QName",
-    )
-    harness.check(
-        iface.identifier.name, "TestIncompleteTypes", "Interface has the right name"
-    )
-    harness.check(len(iface.members), 2, "Expect 2 members")
-
-    attr = iface.members[0]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    method = iface.members[1]
-    harness.ok(isinstance(method, WebIDL.IDLMethod), "Should be an IDLMethod")
-
-    harness.check(
-        attr.identifier.QName(),
-        "::TestIncompleteTypes::attr1",
-        "Attribute has the right QName",
-    )
-    harness.check(
-        attr.type.name, "FooInterface", "Previously unresolved type has the right name"
-    )
-
-    harness.check(
-        method.identifier.QName(),
-        "::TestIncompleteTypes::method1",
-        "Attribute has the right QName",
-    )
-    (returnType, args) = method.signatures()[0]
-    harness.check(
-        returnType.name, "FooInterface", "Previously unresolved type has the right name"
-    )
-    harness.check(
-        args[0].type.name,
-        "FooInterface",
-        "Previously unresolved type has the right name",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interface.py b/components/script/dom/bindings/codegen/parser/tests/test_interface.py
deleted file mode 100644
index 85748848e1b..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_interface.py
+++ /dev/null
@@ -1,459 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse("interface Foo { };")
-    results = parser.finish()
-    harness.ok(True, "Empty interface parsed without error.")
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-    iface = results[0]
-    harness.check(iface.identifier.QName(), "::Foo", "Interface has the right QName")
-    harness.check(iface.identifier.name, "Foo", "Interface has the right name")
-    harness.check(iface.parent, None, "Interface has no parent")
-
-    parser.parse("interface Bar : Foo { };")
-    results = parser.finish()
-    harness.ok(True, "Empty interface parsed without error.")
-    harness.check(len(results), 2, "Should be two productions")
-    harness.ok(isinstance(results[1], WebIDL.IDLInterface), "Should be an IDLInterface")
-    iface = results[1]
-    harness.check(iface.identifier.QName(), "::Bar", "Interface has the right QName")
-    harness.check(iface.identifier.name, "Bar", "Interface has the right name")
-    harness.ok(isinstance(iface.parent, WebIDL.IDLInterface), "Interface has a parent")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface QNameBase {
-          attribute long foo;
-        };
-
-        interface QNameDerived : QNameBase {
-          attribute long long foo;
-          attribute byte bar;
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 2, "Should be two productions")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.ok(isinstance(results[1], WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(results[1].parent, results[0], "Inheritance chain is right")
-    harness.check(len(results[0].members), 1, "Expect 1 productions")
-    harness.check(len(results[1].members), 2, "Expect 2 productions")
-    base = results[0]
-    derived = results[1]
-    harness.check(
-        base.members[0].identifier.QName(),
-        "::QNameBase::foo",
-        "Member has the right QName",
-    )
-    harness.check(
-        derived.members[0].identifier.QName(),
-        "::QNameDerived::foo",
-        "Member has the right QName",
-    )
-    harness.check(
-        derived.members[1].identifier.QName(),
-        "::QNameDerived::bar",
-        "Member has the right QName",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A : B {};
-            interface B : A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow cycles in interface inheritance chains")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A : C {};
-            interface C : B {};
-            interface B : A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw, "Should not allow indirect cycles in interface inheritance chains"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A;
-            interface B : A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should not allow inheriting from an interface that is only forward declared",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface A {
-            constructor();
-            constructor(long arg);
-            readonly attribute boolean x;
-            undefined foo();
-        };
-        partial interface A {
-            readonly attribute boolean y;
-            undefined foo(long arg);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 2, "Should have two results with partial interface")
-    iface = results[0]
-    harness.check(
-        len(iface.members), 3, "Should have three members with partial interface"
-    )
-    harness.check(
-        iface.members[0].identifier.name,
-        "x",
-        "First member should be x with partial interface",
-    )
-    harness.check(
-        iface.members[1].identifier.name,
-        "foo",
-        "Second member should be foo with partial interface",
-    )
-    harness.check(
-        len(iface.members[1].signatures()),
-        2,
-        "Should have two foo signatures with partial interface",
-    )
-    harness.check(
-        iface.members[2].identifier.name,
-        "y",
-        "Third member should be y with partial interface",
-    )
-    harness.check(
-        len(iface.ctor().signatures()),
-        2,
-        "Should have two constructors with partial interface",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        partial interface A {
-            readonly attribute boolean y;
-            undefined foo(long arg);
-        };
-        interface A {
-            constructor();
-            constructor(long arg);
-            readonly attribute boolean x;
-            undefined foo();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results), 2, "Should have two results with reversed partial interface"
-    )
-    iface = results[1]
-    harness.check(
-        len(iface.members),
-        3,
-        "Should have three members with reversed partial interface",
-    )
-    harness.check(
-        iface.members[0].identifier.name,
-        "x",
-        "First member should be x with reversed partial interface",
-    )
-    harness.check(
-        iface.members[1].identifier.name,
-        "foo",
-        "Second member should be foo with reversed partial interface",
-    )
-    harness.check(
-        len(iface.members[1].signatures()),
-        2,
-        "Should have two foo signatures with reversed partial interface",
-    )
-    harness.check(
-        iface.members[2].identifier.name,
-        "y",
-        "Third member should be y with reversed partial interface",
-    )
-    harness.check(
-        len(iface.ctor().signatures()),
-        2,
-        "Should have two constructors with reversed partial interface",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-                readonly attribute boolean x;
-            };
-            interface A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow two non-partial interfaces with the same name")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            partial interface A {
-                readonly attribute boolean x;
-            };
-            partial interface A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Must have a non-partial interface for a given name")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary  A {
-                boolean x;
-            };
-            partial interface A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between partial interface "
-        "and other object",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-                boolean x;
-            };
-            interface A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow a name collision between interface " "and other object"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-                boolean x;
-            };
-            interface A;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between external interface "
-        "and other object",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-                readonly attribute boolean x;
-            };
-            interface A;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between external interface " "and interface",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface A;
-        interface A;
-    """
-    )
-    results = parser.finish()
-    harness.ok(
-        len(results) == 1 and isinstance(results[0], WebIDL.IDLExternalInterface),
-        "Should allow name collisions between external interface " "declarations",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SomeRandomAnnotation]
-            interface A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow unknown extended attributes on interfaces")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Window] interface Window {};
-        [Exposed=Window, LegacyWindowAlias=A]
-        interface B {};
-        [Exposed=Window, LegacyWindowAlias=(C, D)]
-        interface E {};
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        results[1].legacyWindowAliases, ["A"], "Should support a single identifier"
-    )
-    harness.check(
-        results[2].legacyWindowAliases, ["C", "D"], "Should support an identifier list"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyWindowAlias]
-            interface A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow [LegacyWindowAlias] with no value")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Exposed=Worker, LegacyWindowAlias=B]
-            interface A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow [LegacyWindowAlias] without Window exposure")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Window] interface Window {};
-            [Exposed=Window]
-            interface A {};
-            [Exposed=Window, LegacyWindowAlias=A]
-            interface B {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow [LegacyWindowAlias] to conflict with other identifiers"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Window] interface Window {};
-            [Exposed=Window, LegacyWindowAlias=A]
-            interface B {};
-            [Exposed=Window]
-            interface A {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow [LegacyWindowAlias] to conflict with other identifiers"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [Global, Exposed=Window] interface Window {};
-            [Exposed=Window, LegacyWindowAlias=A]
-            interface B {};
-            [Exposed=Window, LegacyWindowAlias=A]
-            interface C {};
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow [LegacyWindowAlias] to conflict with other identifiers"
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interface_const_identifier_conflicts.py b/components/script/dom/bindings/codegen/parser/tests/test_interface_const_identifier_conflicts.py
deleted file mode 100644
index 5750f87a6fc..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_interface_const_identifier_conflicts.py
+++ /dev/null
@@ -1,17 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IdentifierConflict {
-              const byte thing1 = 1;
-              const unsigned long thing1 = 1;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interface_identifier_conflicts_across_members.py b/components/script/dom/bindings/codegen/parser/tests/test_interface_identifier_conflicts_across_members.py
deleted file mode 100644
index c1a544ce718..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_interface_identifier_conflicts_across_members.py
+++ /dev/null
@@ -1,68 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IdentifierConflictAcrossMembers1 {
-              const byte thing1 = 1;
-              readonly attribute long thing1;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IdentifierConflictAcrossMembers2 {
-              readonly attribute long thing1;
-              const byte thing1 = 1;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IdentifierConflictAcrossMembers3 {
-              getter boolean thing1(DOMString name);
-              readonly attribute long thing1;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IdentifierConflictAcrossMembers1 {
-              const byte thing1 = 1;
-              long thing1();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py b/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py
deleted file mode 100644
index 18c6023dd3b..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_interface_maplikesetlikeiterable.py
+++ /dev/null
@@ -1,912 +0,0 @@
-import WebIDL
-import traceback
-
-
-def WebIDLTest(parser, harness):
-    def shouldPass(prefix, iface, expectedMembers, numProductions=1):
-        p = parser.reset()
-        p.parse(iface)
-        results = p.finish()
-        harness.check(
-            len(results),
-            numProductions,
-            "%s - Should have production count %d" % (prefix, numProductions),
-        )
-        harness.ok(
-            isinstance(results[0], WebIDL.IDLInterface),
-            "%s - Should be an IDLInterface" % (prefix),
-        )
-        # Make a copy, since we plan to modify it
-        expectedMembers = list(expectedMembers)
-        for m in results[0].members:
-            name = m.identifier.name
-            if (name, type(m)) in expectedMembers:
-                harness.ok(True, "%s - %s - Should be a %s" % (prefix, name, type(m)))
-                expectedMembers.remove((name, type(m)))
-            else:
-                harness.ok(
-                    False,
-                    "%s - %s - Unknown symbol of type %s" % (prefix, name, type(m)),
-                )
-        # A bit of a hoop because we can't generate the error string if we pass
-        if len(expectedMembers) == 0:
-            harness.ok(True, "Found all the members")
-        else:
-            harness.ok(
-                False,
-                "Expected member not found: %s of type %s"
-                % (expectedMembers[0][0], expectedMembers[0][1]),
-            )
-        return results
-
-    def shouldFail(prefix, iface):
-        try:
-            p = parser.reset()
-            p.parse(iface)
-            p.finish()
-            harness.ok(False, prefix + " - Interface passed when should've failed")
-        except WebIDL.WebIDLError as e:
-            harness.ok(True, prefix + " - Interface failed as expected")
-        except Exception as e:
-            harness.ok(
-                False,
-                prefix
-                + " - Interface failed but not as a WebIDLError exception: %s" % e,
-            )
-
-    iterableMembers = [
-        (x, WebIDL.IDLMethod) for x in ["entries", "keys", "values", "forEach"]
-    ]
-    setROMembers = (
-        [(x, WebIDL.IDLMethod) for x in ["has"]]
-        + [("__setlike", WebIDL.IDLMaplikeOrSetlike)]
-        + iterableMembers
-    )
-    setROMembers.extend([("size", WebIDL.IDLAttribute)])
-    setRWMembers = [
-        (x, WebIDL.IDLMethod) for x in ["add", "clear", "delete"]
-    ] + setROMembers
-    setROChromeMembers = [
-        (x, WebIDL.IDLMethod) for x in ["__add", "__clear", "__delete"]
-    ] + setROMembers
-    setRWChromeMembers = [
-        (x, WebIDL.IDLMethod) for x in ["__add", "__clear", "__delete"]
-    ] + setRWMembers
-    mapROMembers = (
-        [(x, WebIDL.IDLMethod) for x in ["get", "has"]]
-        + [("__maplike", WebIDL.IDLMaplikeOrSetlike)]
-        + iterableMembers
-    )
-    mapROMembers.extend([("size", WebIDL.IDLAttribute)])
-    mapRWMembers = [
-        (x, WebIDL.IDLMethod) for x in ["set", "clear", "delete"]
-    ] + mapROMembers
-    mapRWChromeMembers = [
-        (x, WebIDL.IDLMethod) for x in ["__set", "__clear", "__delete"]
-    ] + mapRWMembers
-
-    # OK, now that we've used iterableMembers to set up the above, append
-    # __iterable to it for the iterable<> case.
-    iterableMembers.append(("__iterable", WebIDL.IDLIterable))
-
-    asyncIterableMembers = [
-        (x, WebIDL.IDLMethod) for x in ["entries", "keys", "values"]
-    ]
-    asyncIterableMembers.append(("__iterable", WebIDL.IDLAsyncIterable))
-
-    valueIterableMembers = [("__iterable", WebIDL.IDLIterable)]
-    valueIterableMembers.append(("__indexedgetter", WebIDL.IDLMethod))
-    valueIterableMembers.append(("length", WebIDL.IDLAttribute))
-
-    valueAsyncIterableMembers = [("__iterable", WebIDL.IDLAsyncIterable)]
-    valueAsyncIterableMembers.append(("values", WebIDL.IDLMethod))
-
-    disallowedIterableNames = ["keys", "entries", "values"]
-    disallowedMemberNames = ["forEach", "has", "size"] + disallowedIterableNames
-    mapDisallowedMemberNames = ["get"] + disallowedMemberNames
-    disallowedNonMethodNames = ["clear", "delete"]
-    mapDisallowedNonMethodNames = ["set"] + disallowedNonMethodNames
-    setDisallowedNonMethodNames = ["add"] + disallowedNonMethodNames
-    unrelatedMembers = [
-        ("unrelatedAttribute", WebIDL.IDLAttribute),
-        ("unrelatedMethod", WebIDL.IDLMethod),
-    ]
-
-    #
-    # Simple Usage Tests
-    #
-
-    shouldPass(
-        "Iterable (key only)",
-        """
-               interface Foo1 {
-               iterable<long>;
-               readonly attribute unsigned long length;
-               getter long(unsigned long index);
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        valueIterableMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Iterable (key only) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               iterable<long>;
-               readonly attribute unsigned long length;
-               getter long(unsigned long index);
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        valueIterableMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Iterable (key and value)",
-        """
-               interface Foo1 {
-               iterable<long, long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        iterableMembers + unrelatedMembers,
-        # numProductions == 2 because of the generated iterator iface,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Iterable (key and value) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               iterable<long, long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        iterableMembers,
-        # numProductions == 3 because of the generated iterator iface,
-        numProductions=3,
-    )
-
-    shouldPass(
-        "Async iterable (key only)",
-        """
-               interface Foo1 {
-               async iterable<long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        valueAsyncIterableMembers + unrelatedMembers,
-        # numProductions == 2 because of the generated iterator iface,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Async iterable (key only) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               async iterable<long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        valueAsyncIterableMembers,
-        # numProductions == 3 because of the generated iterator iface,
-        numProductions=3,
-    )
-
-    shouldPass(
-        "Async iterable with argument (key only)",
-        """
-               interface Foo1 {
-               async iterable<long>(optional long foo);
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        valueAsyncIterableMembers + unrelatedMembers,
-        # numProductions == 2 because of the generated iterator iface,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Async iterable (key and value)",
-        """
-               interface Foo1 {
-               async iterable<long, long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        asyncIterableMembers + unrelatedMembers,
-        # numProductions == 2 because of the generated iterator iface,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Async iterable (key and value) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               async iterable<long, long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        asyncIterableMembers,
-        # numProductions == 3 because of the generated iterator iface,
-        numProductions=3,
-    )
-
-    shouldPass(
-        "Async iterable with argument (key and value)",
-        """
-               interface Foo1 {
-               async iterable<long, long>(optional long foo);
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        asyncIterableMembers + unrelatedMembers,
-        # numProductions == 2 because of the generated iterator iface,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Maplike (readwrite)",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapRWMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Maplike (readwrite) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               maplike<long, long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Maplike (readwrite)",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapRWMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Maplike (readwrite) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               maplike<long, long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Maplike (readonly)",
-        """
-               interface Foo1 {
-               readonly maplike<long, long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapROMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Maplike (readonly) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               readonly maplike<long, long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        mapROMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Setlike (readwrite)",
-        """
-               interface Foo1 {
-               setlike<long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        setRWMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Setlike (readwrite) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               setlike<long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        setRWMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Setlike (readonly)",
-        """
-               interface Foo1 {
-               readonly setlike<long>;
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        setROMembers + unrelatedMembers,
-    )
-
-    shouldPass(
-        "Setlike (readonly) inheriting from parent",
-        """
-               interface Foo1 : Foo2 {
-               readonly setlike<long>;
-               };
-               interface Foo2 {
-               attribute long unrelatedAttribute;
-               long unrelatedMethod();
-               };
-               """,
-        setROMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Inheritance of maplike/setlike",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldFail(
-        "JS Implemented maplike interface",
-        """
-               [JSImplementation="@mozilla.org/dom/test-interface-js-maplike;1"]
-               interface Foo1 {
-               constructor();
-               setlike<long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "JS Implemented maplike interface",
-        """
-               [JSImplementation="@mozilla.org/dom/test-interface-js-maplike;1"]
-               interface Foo1 {
-               constructor();
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    #
-    # Multiple maplike/setlike tests
-    #
-
-    shouldFail(
-        "Two maplike/setlikes on same interface",
-        """
-               interface Foo1 {
-               setlike<long>;
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Two iterable/setlikes on same interface",
-        """
-               interface Foo1 {
-               iterable<long>;
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Two iterables on same interface",
-        """
-               interface Foo1 {
-               iterable<long>;
-               iterable<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Two iterables on same interface",
-        """
-               interface Foo1 {
-               iterable<long>;
-               async iterable<long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Two iterables on same interface",
-        """
-               interface Foo1 {
-               async iterable<long>;
-               async iterable<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Async iterable with non-optional arguments",
-        """
-               interface Foo1 {
-               async iterable<long>(long foo);
-               };
-               """,
-    )
-
-    shouldFail(
-        "Async iterable with non-optional arguments",
-        """
-               interface Foo1 {
-               async iterable<long>(optional long foo, long bar);
-               };
-               """,
-    )
-
-    shouldFail(
-        "Async iterable with non-optional arguments",
-        """
-               interface Foo1 {
-               async iterable<long, long>(long foo);
-               };
-               """,
-    )
-
-    shouldFail(
-        "Two maplike/setlikes in partials",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               partial interface Foo1 {
-               setlike<long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Conflicting maplike/setlikes across inheritance",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               setlike<long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Conflicting maplike/iterable across inheritance",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               iterable<long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Conflicting maplike/setlikes across multistep inheritance",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               setlike<long>;
-               };
-               """,
-    )
-
-    #
-    # Member name collision tests
-    #
-
-    def testConflictingMembers(likeMember, conflictName, expectedMembers, methodPasses):
-        """
-        Tests for maplike/setlike member generation against conflicting member
-        names. If methodPasses is True, this means we expect the interface to
-        pass in the case of method shadowing, and expectedMembers should be the
-        list of interface members to check against on the passing interface.
-
-        """
-        if methodPasses:
-            shouldPass(
-                "Conflicting method: %s and %s" % (likeMember, conflictName),
-                """
-                       interface Foo1 {
-                       %s;
-                       [Throws]
-                       undefined %s(long test1, double test2, double test3);
-                       };
-                       """
-                % (likeMember, conflictName),
-                expectedMembers,
-            )
-        else:
-            shouldFail(
-                "Conflicting method: %s and %s" % (likeMember, conflictName),
-                """
-                       interface Foo1 {
-                       %s;
-                       [Throws]
-                       undefined %s(long test1, double test2, double test3);
-                       };
-                       """
-                % (likeMember, conflictName),
-            )
-        # Inherited conflicting methods should ALWAYS fail
-        shouldFail(
-            "Conflicting inherited method: %s and %s" % (likeMember, conflictName),
-            """
-                   interface Foo1 {
-                   undefined %s(long test1, double test2, double test3);
-                   };
-                   interface Foo2 : Foo1 {
-                   %s;
-                   };
-                   """
-            % (conflictName, likeMember),
-        )
-        shouldFail(
-            "Conflicting static method: %s and %s" % (likeMember, conflictName),
-            """
-                   interface Foo1 {
-                   %s;
-                   static undefined %s(long test1, double test2, double test3);
-                   };
-                   """
-            % (likeMember, conflictName),
-        )
-        shouldFail(
-            "Conflicting attribute: %s and %s" % (likeMember, conflictName),
-            """
-                   interface Foo1 {
-                   %s
-                   attribute double %s;
-                   };
-                   """
-            % (likeMember, conflictName),
-        )
-        shouldFail(
-            "Conflicting const: %s and %s" % (likeMember, conflictName),
-            """
-                   interface Foo1 {
-                   %s;
-                   const double %s = 0;
-                   };
-                   """
-            % (likeMember, conflictName),
-        )
-        shouldFail(
-            "Conflicting static attribute: %s and %s" % (likeMember, conflictName),
-            """
-                   interface Foo1 {
-                   %s;
-                   static attribute long %s;
-                   };
-                   """
-            % (likeMember, conflictName),
-        )
-
-    for member in disallowedIterableNames:
-        testConflictingMembers("iterable<long, long>", member, iterableMembers, False)
-    for member in mapDisallowedMemberNames:
-        testConflictingMembers("maplike<long, long>", member, mapRWMembers, False)
-    for member in disallowedMemberNames:
-        testConflictingMembers("setlike<long>", member, setRWMembers, False)
-    for member in mapDisallowedNonMethodNames:
-        testConflictingMembers("maplike<long, long>", member, mapRWMembers, True)
-    for member in setDisallowedNonMethodNames:
-        testConflictingMembers("setlike<long>", member, setRWMembers, True)
-
-    shouldPass(
-        "Inheritance of maplike/setlike with child member collision",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               undefined entries();
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Inheritance of multi-level maplike/setlike with child member collision",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               undefined entries();
-               };
-               """,
-        mapRWMembers,
-        numProductions=3,
-    )
-
-    shouldFail(
-        "Maplike interface with mixin member collision",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface mixin Foo2 {
-               undefined entries();
-               };
-               Foo1 includes Foo2;
-               """,
-    )
-
-    shouldPass(
-        "Inherited Maplike interface with consequential interface member collision",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface mixin Foo2 {
-               undefined entries();
-               };
-               interface Foo3 : Foo1 {
-               };
-               Foo3 includes Foo2;
-               """,
-        mapRWMembers,
-        numProductions=4,
-    )
-
-    shouldFail(
-        "Inheritance of name collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               undefined entries();
-               };
-               interface Foo2 : Foo1 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Inheritance of multi-level name collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               undefined entries();
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldPass(
-        "Inheritance of attribute collision with parent maplike/setlike",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               attribute double size;
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldPass(
-        "Inheritance of multi-level attribute collision with parent maplike/setlike",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               attribute double size;
-               };
-               """,
-        mapRWMembers,
-        numProductions=3,
-    )
-
-    shouldFail(
-        "Inheritance of attribute collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               attribute double size;
-               };
-               interface Foo2 : Foo1 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Inheritance of multi-level attribute collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               attribute double size;
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Inheritance of attribute/rw function collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               attribute double set;
-               };
-               interface Foo2 : Foo1 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Inheritance of const/rw function collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               const double set = 0;
-               };
-               interface Foo2 : Foo1 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldPass(
-        "Inheritance of rw function with same name in child maplike/setlike",
-        """
-               interface Foo1 {
-               maplike<long, long>;
-               };
-               interface Foo2 : Foo1 {
-               undefined clear();
-               };
-               """,
-        mapRWMembers,
-        numProductions=2,
-    )
-
-    shouldFail(
-        "Inheritance of unforgeable attribute collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               [LegacyUnforgeable]
-               attribute double size;
-               };
-               interface Foo2 : Foo1 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldFail(
-        "Inheritance of multi-level unforgeable attribute collision with child maplike/setlike",
-        """
-               interface Foo1 {
-               [LegacyUnforgeable]
-               attribute double size;
-               };
-               interface Foo2 : Foo1 {
-               };
-               interface Foo3 : Foo2 {
-               maplike<long, long>;
-               };
-               """,
-    )
-
-    shouldPass(
-        "Interface with readonly allowable overrides",
-        """
-               interface Foo1 {
-               readonly setlike<long>;
-               readonly attribute boolean clear;
-               };
-               """,
-        setROMembers + [("clear", WebIDL.IDLAttribute)],
-    )
-
-    r = shouldPass(
-        "Check proper override of clear/delete/set",
-        """
-                   interface Foo1 {
-                   maplike<long, long>;
-                   long clear(long a, long b, double c, double d);
-                   long set(long a, long b, double c, double d);
-                   long delete(long a, long b, double c, double d);
-                   };
-                   """,
-        mapRWMembers,
-    )
-
-    for m in r[0].members:
-        if m.identifier.name in ["clear", "set", "delete"]:
-            harness.ok(m.isMethod(), "%s should be a method" % m.identifier.name)
-            harness.check(
-                m.maxArgCount, 4, "%s should have 4 arguments" % m.identifier.name
-            )
-            harness.ok(
-                not m.isMaplikeOrSetlikeOrIterableMethod(),
-                "%s should not be a maplike/setlike function" % m.identifier.name,
-            )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_interfacemixin.py b/components/script/dom/bindings/codegen/parser/tests/test_interfacemixin.py
deleted file mode 100644
index b3c8573fa59..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_interfacemixin.py
+++ /dev/null
@@ -1,534 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse("interface mixin Foo { };")
-    results = parser.finish()
-    harness.ok(True, "Empty interface mixin parsed without error.")
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(
-        isinstance(results[0], WebIDL.IDLInterfaceMixin),
-        "Should be an IDLInterfaceMixin",
-    )
-    mixin = results[0]
-    harness.check(
-        mixin.identifier.QName(), "::Foo", "Interface mixin has the right QName"
-    )
-    harness.check(mixin.identifier.name, "Foo", "Interface mixin has the right name")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface mixin QNameBase {
-            const long foo = 3;
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(len(results), 1, "Should be one productions")
-    harness.ok(
-        isinstance(results[0], WebIDL.IDLInterfaceMixin),
-        "Should be an IDLInterfaceMixin",
-    )
-    harness.check(len(results[0].members), 1, "Expect 1 productions")
-    mixin = results[0]
-    harness.check(
-        mixin.members[0].identifier.QName(),
-        "::QNameBase::foo",
-        "Member has the right QName",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface mixin A {
-            readonly attribute boolean x;
-            undefined foo();
-        };
-        partial interface mixin A {
-            readonly attribute boolean y;
-            undefined foo(long arg);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results), 2, "Should have two results with partial interface mixin"
-    )
-    mixin = results[0]
-    harness.check(
-        len(mixin.members), 3, "Should have three members with partial interface mixin"
-    )
-    harness.check(
-        mixin.members[0].identifier.name,
-        "x",
-        "First member should be x with partial interface mixin",
-    )
-    harness.check(
-        mixin.members[1].identifier.name,
-        "foo",
-        "Second member should be foo with partial interface mixin",
-    )
-    harness.check(
-        len(mixin.members[1].signatures()),
-        2,
-        "Should have two foo signatures with partial interface mixin",
-    )
-    harness.check(
-        mixin.members[2].identifier.name,
-        "y",
-        "Third member should be y with partial interface mixin",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        partial interface mixin A {
-            readonly attribute boolean y;
-            undefined foo(long arg);
-        };
-        interface mixin A {
-            readonly attribute boolean x;
-            undefined foo();
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results), 2, "Should have two results with reversed partial interface mixin"
-    )
-    mixin = results[1]
-    harness.check(
-        len(mixin.members),
-        3,
-        "Should have three members with reversed partial interface mixin",
-    )
-    harness.check(
-        mixin.members[0].identifier.name,
-        "x",
-        "First member should be x with reversed partial interface mixin",
-    )
-    harness.check(
-        mixin.members[1].identifier.name,
-        "foo",
-        "Second member should be foo with reversed partial interface mixin",
-    )
-    harness.check(
-        len(mixin.members[1].signatures()),
-        2,
-        "Should have two foo signatures with reversed partial interface mixin",
-    )
-    harness.check(
-        mixin.members[2].identifier.name,
-        "y",
-        "Third member should be y with reversed partial interface mixin",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface Interface {};
-        interface mixin Mixin {
-            attribute short x;
-        };
-        Interface includes Mixin;
-    """
-    )
-    results = parser.finish()
-    iface = results[0]
-    harness.check(len(iface.members), 1, "Should merge members from mixins")
-    harness.check(
-        iface.members[0].identifier.name, "x", "Should merge members from mixins"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                readonly attribute boolean x;
-            };
-            interface mixin A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow two non-partial interface mixins with the same name"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            partial interface mixin A {
-                readonly attribute boolean x;
-            };
-            partial interface mixin A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Must have a non-partial interface mixin for a given name")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-                boolean x;
-            };
-            partial interface mixin A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between partial interface "
-        "mixin and other object",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary A {
-                boolean x;
-            };
-            interface mixin A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between interface mixin " "and other object",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                readonly attribute boolean x;
-            };
-            interface A;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a name collision between external interface "
-        "and interface mixin",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SomeRandomAnnotation]
-            interface mixin A {
-                readonly attribute boolean y;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow unknown extended attributes on interface mixins"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                getter double (DOMString propertyName);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow getters on interface mixins")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                setter undefined (DOMString propertyName, double propertyValue);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow setters on interface mixins")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                deleter undefined (DOMString propertyName);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow deleters on interface mixins")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                legacycaller double compute(double x);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow legacycallers on interface mixins")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin A {
-                inherit attribute x;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow inherited attribute on interface mixins")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Interface {};
-            interface NotMixin {
-                attribute short x;
-            };
-            Interface includes NotMixin;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should fail if the right side does not point an interface mixin")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin NotInterface {};
-            interface mixin Mixin {
-                attribute short x;
-            };
-            NotInterface includes Mixin;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should fail if the left side does not point an interface")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin Mixin {
-                iterable<DOMString>;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should fail if an interface mixin includes iterable")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin Mixin {
-                setlike<DOMString>;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should fail if an interface mixin includes setlike")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface mixin Mixin {
-                maplike<DOMString, DOMString>;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should fail if an interface mixin includes maplike")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Interface {
-                attribute short attr;
-            };
-            interface mixin Mixin {
-                attribute short attr;
-            };
-            Interface includes Mixin;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should fail if the included mixin interface has duplicated member"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Interface {};
-            interface mixin Mixin1 {
-                attribute short attr;
-            };
-            interface mixin Mixin2 {
-                attribute short attr;
-            };
-            Interface includes Mixin1;
-            Interface includes Mixin2;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should fail if the included mixin interfaces have duplicated member"
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Window] interface Window {};
-        [Global, Exposed=Worker] interface Worker {};
-        [Exposed=Window]
-        interface Base {};
-        interface mixin Mixin {
-            Base returnSelf();
-        };
-        Base includes Mixin;
-    """
-    )
-    results = parser.finish()
-    base = results[2]
-    attr = base.members[0]
-    harness.check(
-        attr.exposureSet,
-        set(["Window"]),
-        "Should expose on globals where the base interfaces are exposed",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Window] interface Window {};
-        [Global, Exposed=Worker] interface Worker {};
-        [Exposed=Window]
-        interface Base {};
-        [Exposed=Window]
-        interface mixin Mixin {
-            attribute short a;
-        };
-        Base includes Mixin;
-    """
-    )
-    results = parser.finish()
-    base = results[2]
-    attr = base.members[0]
-    harness.check(
-        attr.exposureSet, set(["Window"]), "Should follow [Exposed] on interface mixin"
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        [Global, Exposed=Window] interface Window {};
-        [Global, Exposed=Worker] interface Worker {};
-        [Exposed=Window]
-        interface Base1 {};
-        [Exposed=Worker]
-        interface Base2 {};
-        interface mixin Mixin {
-            attribute short a;
-        };
-        Base1 includes Mixin;
-        Base2 includes Mixin;
-    """
-    )
-    results = parser.finish()
-    base = results[2]
-    attr = base.members[0]
-    harness.check(
-        attr.exposureSet,
-        set(["Window", "Worker"]),
-        "Should expose on all globals where including interfaces are " "exposed",
-    )
-    base = results[3]
-    attr = base.members[0]
-    harness.check(
-        attr.exposureSet,
-        set(["Window", "Worker"]),
-        "Should expose on all globals where including interfaces are " "exposed",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_lenientSetter.py b/components/script/dom/bindings/codegen/parser/tests/test_lenientSetter.py
deleted file mode 100644
index 9d2230c3bec..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_lenientSetter.py
+++ /dev/null
@@ -1,84 +0,0 @@
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-
-def should_throw(parser, harness, message, code):
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(code)
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown: %s" % message)
-
-
-def WebIDLTest(parser, harness):
-    # The [LegacyLenientSetter] extended attribute MUST take no arguments.
-    should_throw(
-        parser,
-        harness,
-        "no arguments",
-        """
-        interface I {
-          [LegacyLenientSetter=X] readonly attribute long A;
-        };
-    """,
-    )
-
-    # An attribute with the [LegacyLenientSetter] extended attribute MUST NOT
-    # also be declared with the [PutForwards] extended attribute.
-    should_throw(
-        parser,
-        harness,
-        "PutForwards",
-        """
-        interface I {
-          [PutForwards=B, LegacyLenientSetter] readonly attribute J A;
-        };
-        interface J {
-          attribute long B;
-        };
-    """,
-    )
-
-    # An attribute with the [LegacyLenientSetter] extended attribute MUST NOT
-    # also be declared with the [Replaceable] extended attribute.
-    should_throw(
-        parser,
-        harness,
-        "Replaceable",
-        """
-        interface I {
-          [Replaceable, LegacyLenientSetter] readonly attribute J A;
-        };
-    """,
-    )
-
-    # The [LegacyLenientSetter] extended attribute MUST NOT be used on an
-    # attribute that is not read only.
-    should_throw(
-        parser,
-        harness,
-        "writable attribute",
-        """
-        interface I {
-          [LegacyLenientSetter] attribute long A;
-        };
-    """,
-    )
-
-    # The [LegacyLenientSetter] extended attribute MUST NOT be used on a
-    # static attribute.
-    should_throw(
-        parser,
-        harness,
-        "static attribute",
-        """
-        interface I {
-          [LegacyLenientSetter] static readonly attribute long A;
-        };
-    """,
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_method.py b/components/script/dom/bindings/codegen/parser/tests/test_method.py
deleted file mode 100644
index 0ddfada28ac..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_method.py
+++ /dev/null
@@ -1,430 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestMethods {
-          undefined basic();
-          static undefined basicStatic();
-          undefined basicWithSimpleArgs(boolean arg1, byte arg2, unsigned long arg3);
-          boolean basicBoolean();
-          static boolean basicStaticBoolean();
-          boolean basicBooleanWithSimpleArgs(boolean arg1, byte arg2, unsigned long arg3);
-          undefined optionalArg(optional byte? arg1, optional sequence<byte> arg2);
-          undefined variadicArg(byte?... arg1);
-          object getObject();
-          undefined setObject(object arg1);
-          undefined setAny(any arg1);
-          float doFloats(float arg1);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestMethods interface parsed without error.")
-    harness.check(len(results), 1, "Should be one production.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestMethods", "Interface has the right QName"
-    )
-    harness.check(iface.identifier.name, "TestMethods", "Interface has the right name")
-    harness.check(len(iface.members), 12, "Expect 12 members")
-
-    methods = iface.members
-
-    def checkArgument(argument, QName, name, type, optional, variadic):
-        harness.ok(isinstance(argument, WebIDL.IDLArgument), "Should be an IDLArgument")
-        harness.check(
-            argument.identifier.QName(), QName, "Argument has the right QName"
-        )
-        harness.check(argument.identifier.name, name, "Argument has the right name")
-        harness.check(str(argument.type), type, "Argument has the right return type")
-        harness.check(
-            argument.optional, optional, "Argument has the right optional value"
-        )
-        harness.check(
-            argument.variadic, variadic, "Argument has the right variadic value"
-        )
-
-    def checkMethod(
-        method,
-        QName,
-        name,
-        signatures,
-        static=False,
-        getter=False,
-        setter=False,
-        deleter=False,
-        legacycaller=False,
-        stringifier=False,
-    ):
-        harness.ok(isinstance(method, WebIDL.IDLMethod), "Should be an IDLMethod")
-        harness.ok(method.isMethod(), "Method is a method")
-        harness.ok(not method.isAttr(), "Method is not an attr")
-        harness.ok(not method.isConst(), "Method is not a const")
-        harness.check(method.identifier.QName(), QName, "Method has the right QName")
-        harness.check(method.identifier.name, name, "Method has the right name")
-        harness.check(method.isStatic(), static, "Method has the correct static value")
-        harness.check(method.isGetter(), getter, "Method has the correct getter value")
-        harness.check(method.isSetter(), setter, "Method has the correct setter value")
-        harness.check(
-            method.isDeleter(), deleter, "Method has the correct deleter value"
-        )
-        harness.check(
-            method.isLegacycaller(),
-            legacycaller,
-            "Method has the correct legacycaller value",
-        )
-        harness.check(
-            method.isStringifier(),
-            stringifier,
-            "Method has the correct stringifier value",
-        )
-        harness.check(
-            len(method.signatures()),
-            len(signatures),
-            "Method has the correct number of signatures",
-        )
-
-        sigpairs = zip(method.signatures(), signatures)
-        for (gotSignature, expectedSignature) in sigpairs:
-            (gotRetType, gotArgs) = gotSignature
-            (expectedRetType, expectedArgs) = expectedSignature
-
-            harness.check(
-                str(gotRetType), expectedRetType, "Method has the expected return type."
-            )
-
-            for i in range(0, len(gotArgs)):
-                (QName, name, type, optional, variadic) = expectedArgs[i]
-                checkArgument(gotArgs[i], QName, name, type, optional, variadic)
-
-    checkMethod(methods[0], "::TestMethods::basic", "basic", [("Undefined", [])])
-    checkMethod(
-        methods[1],
-        "::TestMethods::basicStatic",
-        "basicStatic",
-        [("Undefined", [])],
-        static=True,
-    )
-    checkMethod(
-        methods[2],
-        "::TestMethods::basicWithSimpleArgs",
-        "basicWithSimpleArgs",
-        [
-            (
-                "Undefined",
-                [
-                    (
-                        "::TestMethods::basicWithSimpleArgs::arg1",
-                        "arg1",
-                        "Boolean",
-                        False,
-                        False,
-                    ),
-                    (
-                        "::TestMethods::basicWithSimpleArgs::arg2",
-                        "arg2",
-                        "Byte",
-                        False,
-                        False,
-                    ),
-                    (
-                        "::TestMethods::basicWithSimpleArgs::arg3",
-                        "arg3",
-                        "UnsignedLong",
-                        False,
-                        False,
-                    ),
-                ],
-            )
-        ],
-    )
-    checkMethod(
-        methods[3], "::TestMethods::basicBoolean", "basicBoolean", [("Boolean", [])]
-    )
-    checkMethod(
-        methods[4],
-        "::TestMethods::basicStaticBoolean",
-        "basicStaticBoolean",
-        [("Boolean", [])],
-        static=True,
-    )
-    checkMethod(
-        methods[5],
-        "::TestMethods::basicBooleanWithSimpleArgs",
-        "basicBooleanWithSimpleArgs",
-        [
-            (
-                "Boolean",
-                [
-                    (
-                        "::TestMethods::basicBooleanWithSimpleArgs::arg1",
-                        "arg1",
-                        "Boolean",
-                        False,
-                        False,
-                    ),
-                    (
-                        "::TestMethods::basicBooleanWithSimpleArgs::arg2",
-                        "arg2",
-                        "Byte",
-                        False,
-                        False,
-                    ),
-                    (
-                        "::TestMethods::basicBooleanWithSimpleArgs::arg3",
-                        "arg3",
-                        "UnsignedLong",
-                        False,
-                        False,
-                    ),
-                ],
-            )
-        ],
-    )
-    checkMethod(
-        methods[6],
-        "::TestMethods::optionalArg",
-        "optionalArg",
-        [
-            (
-                "Undefined",
-                [
-                    (
-                        "::TestMethods::optionalArg::arg1",
-                        "arg1",
-                        "ByteOrNull",
-                        True,
-                        False,
-                    ),
-                    (
-                        "::TestMethods::optionalArg::arg2",
-                        "arg2",
-                        "ByteSequence",
-                        True,
-                        False,
-                    ),
-                ],
-            )
-        ],
-    )
-    checkMethod(
-        methods[7],
-        "::TestMethods::variadicArg",
-        "variadicArg",
-        [
-            (
-                "Undefined",
-                [
-                    (
-                        "::TestMethods::variadicArg::arg1",
-                        "arg1",
-                        "ByteOrNull",
-                        True,
-                        True,
-                    )
-                ],
-            )
-        ],
-    )
-    checkMethod(methods[8], "::TestMethods::getObject", "getObject", [("Object", [])])
-    checkMethod(
-        methods[9],
-        "::TestMethods::setObject",
-        "setObject",
-        [
-            (
-                "Undefined",
-                [("::TestMethods::setObject::arg1", "arg1", "Object", False, False)],
-            )
-        ],
-    )
-    checkMethod(
-        methods[10],
-        "::TestMethods::setAny",
-        "setAny",
-        [("Undefined", [("::TestMethods::setAny::arg1", "arg1", "Any", False, False)])],
-    )
-    checkMethod(
-        methods[11],
-        "::TestMethods::doFloats",
-        "doFloats",
-        [("Float", [("::TestMethods::doFloats::arg1", "arg1", "Float", False, False)])],
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            undefined foo(optional float bar = 1);
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(not threw, "Should allow integer to float type corecion")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [GetterThrows] undefined foo();
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should not allow [GetterThrows] on methods")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [SetterThrows] undefined foo();
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should not allow [SetterThrows] on methods")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throw] undefined foo();
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should spell [Throws] correctly on methods")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            undefined __noSuchMethod__();
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should not allow __noSuchMethod__ methods")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throws, LenientFloat]
-            undefined foo(float myFloat);
-            [Throws]
-            undefined foo();
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(not threw, "Should allow LenientFloat to be only in a specific overload")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      interface A {
-        [Throws]
-        undefined foo();
-        [Throws, LenientFloat]
-        undefined foo(float myFloat);
-      };
-    """
-    )
-    results = parser.finish()
-    iface = results[0]
-    methods = iface.members
-    lenientFloat = methods[0].getExtendedAttribute("LenientFloat")
-    harness.ok(
-        lenientFloat is not None,
-        "LenientFloat in overloads must be added to the method",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throws, LenientFloat]
-            undefined foo(float myFloat);
-            [Throws]
-            undefined foo(float myFloat, float yourFloat);
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw,
-        "Should prevent overloads from getting different restricted float behavior",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throws]
-            undefined foo(float myFloat, float yourFloat);
-            [Throws, LenientFloat]
-            undefined foo(float myFloat);
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw,
-        "Should prevent overloads from getting different restricted float behavior (2)",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface A {
-            [Throws, LenientFloat]
-            undefined foo(float myFloat);
-            [Throws, LenientFloat]
-            undefined foo(short myShort);
-          };
-        """
-        )
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should prevent overloads from getting redundant [LenientFloat]")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_namespace.py b/components/script/dom/bindings/codegen/parser/tests/test_namespace.py
deleted file mode 100644
index 247c5b22232..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_namespace.py
+++ /dev/null
@@ -1,232 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        namespace MyNamespace {
-          attribute any foo;
-          any bar();
-        };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(len(results), 1, "Should have a thing.")
-    harness.ok(results[0].isNamespace(), "Our thing should be a namespace")
-    harness.check(len(results[0].members), 2, "Should have two things in our namespace")
-    harness.ok(results[0].members[0].isAttr(), "First member is attribute")
-    harness.ok(results[0].members[0].isStatic(), "Attribute should be static")
-    harness.ok(results[0].members[1].isMethod(), "Second member is method")
-    harness.ok(results[0].members[1].isStatic(), "Operation should be static")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        namespace MyNamespace {
-          attribute any foo;
-        };
-        partial namespace MyNamespace {
-          any bar();
-        };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(len(results), 2, "Should have things.")
-    harness.ok(results[0].isNamespace(), "Our thing should be a namespace")
-    harness.check(len(results[0].members), 2, "Should have two things in our namespace")
-    harness.ok(results[0].members[0].isAttr(), "First member is attribute")
-    harness.ok(results[0].members[0].isStatic(), "Attribute should be static")
-    harness.ok(results[0].members[1].isMethod(), "Second member is method")
-    harness.ok(results[0].members[1].isStatic(), "Operation should be static")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        partial namespace MyNamespace {
-          any bar();
-        };
-        namespace MyNamespace {
-          attribute any foo;
-        };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(len(results), 2, "Should have things.")
-    harness.ok(results[1].isNamespace(), "Our thing should be a namespace")
-    harness.check(len(results[1].members), 2, "Should have two things in our namespace")
-    harness.ok(results[1].members[0].isAttr(), "First member is attribute")
-    harness.ok(results[1].members[0].isStatic(), "Attribute should be static")
-    harness.ok(results[1].members[1].isMethod(), "Second member is method")
-    harness.ok(results[1].members[1].isStatic(), "Operation should be static")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            namespace MyNamespace {
-              static attribute any foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            namespace MyNamespace {
-              static any bar();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            namespace MyNamespace {
-              any bar();
-            };
-
-            interface MyNamespace {
-              any baz();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface MyNamespace {
-              any baz();
-            };
-
-            namespace MyNamespace {
-              any bar();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            namespace MyNamespace {
-              any baz();
-            };
-
-            namespace MyNamespace {
-              any bar();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            partial namespace MyNamespace {
-              any baz();
-            };
-
-            interface MyNamespace {
-              any bar();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            namespace MyNamespace {
-              any bar();
-            };
-
-            partial interface MyNamespace {
-              any baz();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            partial interface MyNamespace {
-              any baz();
-            };
-
-            namespace MyNamespace {
-              any bar();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface MyNamespace {
-              any bar();
-            };
-
-            partial namespace MyNamespace {
-              any baz();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_newobject.py b/components/script/dom/bindings/codegen/parser/tests/test_newobject.py
deleted file mode 100644
index c12995a0e86..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_newobject.py
+++ /dev/null
@@ -1,76 +0,0 @@
-# Import the WebIDL module, so we can do isinstance checks and whatnot
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    # Basic functionality
-    parser.parse(
-        """
-        interface Iface {
-          [NewObject] readonly attribute Iface attr;
-          [NewObject] Iface method();
-        };
-        """
-    )
-    results = parser.finish()
-    harness.ok(results, "Should not have thrown on basic [NewObject] usage")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Iface {
-              [Pure, NewObject] readonly attribute Iface attr;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[NewObject] attributes must depend on something")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Iface {
-              [Pure, NewObject] Iface method();
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[NewObject] methods must depend on something")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Iface {
-              [Cached, NewObject, Affects=Nothing] readonly attribute Iface attr;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[NewObject] attributes must not be [Cached]")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Iface {
-              [StoreInSlot, NewObject, Affects=Nothing] readonly attribute Iface attr;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[NewObject] attributes must not be [StoreInSlot]")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_nullable_equivalency.py b/components/script/dom/bindings/codegen/parser/tests/test_nullable_equivalency.py
deleted file mode 100644
index 012c5fcff7c..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_nullable_equivalency.py
+++ /dev/null
@@ -1,141 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestNullableEquivalency1 {
-          attribute long  a;
-          attribute long? b;
-        };
-
-        interface TestNullableEquivalency2 {
-          attribute ArrayBuffer  a;
-          attribute ArrayBuffer? b;
-        };
-
-        /* Can't have dictionary-valued attributes, so can't test that here */
-
-        enum TestNullableEquivalency4Enum {
-          "Foo",
-          "Bar"
-        };
-
-        interface TestNullableEquivalency4 {
-          attribute TestNullableEquivalency4Enum  a;
-          attribute TestNullableEquivalency4Enum? b;
-        };
-
-        interface TestNullableEquivalency5 {
-          attribute TestNullableEquivalency4  a;
-          attribute TestNullableEquivalency4? b;
-        };
-
-        interface TestNullableEquivalency6 {
-          attribute boolean  a;
-          attribute boolean? b;
-        };
-
-        interface TestNullableEquivalency7 {
-          attribute DOMString  a;
-          attribute DOMString? b;
-        };
-
-        interface TestNullableEquivalency8 {
-          attribute float  a;
-          attribute float? b;
-        };
-
-        interface TestNullableEquivalency9 {
-          attribute double  a;
-          attribute double? b;
-        };
-
-        interface TestNullableEquivalency10 {
-          attribute object  a;
-          attribute object? b;
-        };
-    """
-    )
-
-    for decl in parser.finish():
-        if decl.isInterface():
-            checkEquivalent(decl, harness)
-
-
-def checkEquivalent(iface, harness):
-    type1 = iface.members[0].type
-    type2 = iface.members[1].type
-
-    harness.check(type1.nullable(), False, "attr1 should not be nullable")
-    harness.check(type2.nullable(), True, "attr2 should be nullable")
-
-    # We don't know about type1, but type2, the nullable type, definitely
-    # shouldn't be builtin.
-    harness.check(type2.builtin, False, "attr2 should not be builtin")
-
-    # Ensure that all attributes of type2 match those in type1, except for:
-    #  - names on an ignore list,
-    #  - names beginning with '_',
-    #  - functions which throw when called with no args, and
-    #  - class-level non-callables ("static variables").
-    #
-    # Yes, this is an ugly, fragile hack.  But it finds bugs...
-    for attr in dir(type1):
-        if (
-            attr.startswith("_")
-            or attr
-            in [
-                "nullable",
-                "builtin",
-                "filename",
-                "location",
-                "inner",
-                "QName",
-                "getDeps",
-                "name",
-                "prettyName",
-            ]
-            or (hasattr(type(type1), attr) and not callable(getattr(type1, attr)))
-        ):
-            continue
-
-        a1 = getattr(type1, attr)
-
-        if callable(a1):
-            try:
-                v1 = a1()
-            except:
-                # Can't call a1 with no args, so skip this attriute.
-                continue
-
-            try:
-                a2 = getattr(type2, attr)
-            except:
-                harness.ok(
-                    False,
-                    "Missing %s attribute on type %s in %s" % (attr, type2, iface),
-                )
-                continue
-
-            if not callable(a2):
-                harness.ok(
-                    False,
-                    "%s attribute on type %s in %s wasn't callable"
-                    % (attr, type2, iface),
-                )
-                continue
-
-            v2 = a2()
-            harness.check(v2, v1, "%s method return value" % attr)
-        else:
-            try:
-                a2 = getattr(type2, attr)
-            except:
-                harness.ok(
-                    False,
-                    "Missing %s attribute on type %s in %s" % (attr, type2, iface),
-                )
-                continue
-
-            harness.check(a2, a1, "%s attribute should match" % attr)
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_observableArray.py b/components/script/dom/bindings/codegen/parser/tests/test_observableArray.py
deleted file mode 100644
index 601f626bcf4..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_observableArray.py
+++ /dev/null
@@ -1,288 +0,0 @@
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-
-def WebIDLTest(parser, harness):
-
-    # Test dictionary as inner type
-    harness.should_throw(
-        parser,
-        """
-        dictionary A {
-          boolean member;
-        };
-        interface B {
-          attribute ObservableArray<A> foo;
-        };
-        """,
-        "use dictionary as inner type",
-    )
-
-    # Test sequence as inner type
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          attribute ObservableArray<sequence<boolean>> foo;
-        };
-        """,
-        "use sequence as inner type",
-    )
-
-    # Test sequence<dictionary> as inner type
-    harness.should_throw(
-        parser,
-        """
-        dictionary A {
-            boolean member;
-        };
-        interface B {
-          attribute ObservableArray<sequence<A>> foo;
-        };
-        """,
-        "use sequence<dictionary> as inner type",
-    )
-
-    # Test record as inner type
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          attribute ObservableArray<record<DOMString, boolean>> foo;
-        };
-        """,
-        "use record as inner type",
-    )
-
-    # Test record<dictionary> as inner type
-    harness.should_throw(
-        parser,
-        """
-        dictionary A {
-            boolean member;
-        };
-        interface B {
-          attribute ObservableArray<record<DOMString, A>> foo;
-        };
-        """,
-        "use record<dictionary> as inner type",
-    )
-
-    # Test observable array as inner type
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          attribute ObservableArray<ObservableArray<boolean>> foo;
-        };
-        """,
-        "use ObservableArray as inner type",
-    )
-
-    # Test nullable attribute
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          attribute ObservableArray<boolean>? foo;
-        };
-        """,
-        "nullable",
-    )
-
-    # Test sequence
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          undefined foo(sequence<ObservableArray<boolean>> foo);
-        };
-        """,
-        "used in sequence",
-    )
-
-    # Test record
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          undefined foo(record<DOMString, ObservableArray<boolean>> foo);
-        };
-        """,
-        "used in record",
-    )
-
-    # Test promise
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          Promise<ObservableArray<boolean>> foo();
-        };
-        """,
-        "used in promise",
-    )
-
-    # Test union
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          attribute (DOMString or ObservableArray<boolean>>) foo;
-        };
-        """,
-        "used in union",
-    )
-
-    # Test dictionary member
-    harness.should_throw(
-        parser,
-        """
-        dictionary A {
-          ObservableArray<boolean> foo;
-        };
-        """,
-        "used on dictionary member type",
-    )
-
-    # Test argument
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          undefined foo(ObservableArray<boolean> foo);
-        };
-        """,
-        "used on argument",
-    )
-
-    # Test static attribute
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          static attribute ObservableArray<boolean> foo;
-        };
-        """,
-        "used on static attribute type",
-    )
-
-    # Test iterable
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          iterable<ObservableArray<boolean>>;
-        };
-        """,
-        "used in iterable",
-    )
-
-    # Test maplike
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          maplike<long, ObservableArray<boolean>>;
-        };
-        """,
-        "used in maplike",
-    )
-
-    # Test setlike
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          setlike<ObservableArray<boolean>>;
-        };
-        """,
-        "used in setlike",
-    )
-
-    # Test JS implemented interface
-    harness.should_throw(
-        parser,
-        """
-        [JSImplementation="@mozilla.org/dom/test-interface-js;1"]
-        interface A {
-          readonly attribute ObservableArray<boolean> foo;
-        };
-        """,
-        "used in JS implemented interface",
-    )
-
-    # Test namespace
-    harness.should_throw(
-        parser,
-        """
-        namespace A {
-          readonly attribute ObservableArray<boolean> foo;
-        };
-        """,
-        "used in namespaces",
-    )
-
-    # Test [Cached] extended attribute
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          [Cached, Pure]
-          readonly attribute ObservableArray<boolean> foo;
-        };
-        """,
-        "have Cached extended attribute",
-    )
-
-    # Test [StoreInSlot] extended attribute
-    harness.should_throw(
-        parser,
-        """
-        interface A {
-          [StoreInSlot, Pure]
-          readonly attribute ObservableArray<boolean> foo;
-        };
-        """,
-        "have StoreInSlot extended attribute",
-    )
-
-    # Test regular attribute
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface A {
-          readonly attribute ObservableArray<boolean> foo;
-          attribute ObservableArray<[Clamp] octet> bar;
-          attribute ObservableArray<long?> baz;
-          attribute ObservableArray<(boolean or long)> qux;
-        };
-        """
-    )
-    results = parser.finish()
-    A = results[0]
-    foo = A.members[0]
-    harness.ok(foo.readonly, "A.foo is readonly attribute")
-    harness.ok(foo.type.isObservableArray(), "A.foo is ObservableArray type")
-    harness.check(
-        foo.slotIndices[A.identifier.name], 0, "A.foo should be stored in slot"
-    )
-    bar = A.members[1]
-    harness.ok(bar.type.isObservableArray(), "A.bar is ObservableArray type")
-    harness.check(
-        bar.slotIndices[A.identifier.name], 1, "A.bar should be stored in slot"
-    )
-    harness.ok(bar.type.inner.hasClamp(), "A.bar's inner type should be clamped")
-    baz = A.members[2]
-    harness.ok(baz.type.isObservableArray(), "A.baz is ObservableArray type")
-    harness.check(
-        baz.slotIndices[A.identifier.name], 2, "A.baz should be stored in slot"
-    )
-    harness.ok(baz.type.inner.nullable(), "A.baz's inner type should be nullable")
-    qux = A.members[3]
-    harness.ok(qux.type.isObservableArray(), "A.qux is ObservableArray type")
-    harness.check(
-        qux.slotIndices[A.identifier.name], 3, "A.qux should be stored in slot"
-    )
-    harness.ok(qux.type.inner.isUnion(), "A.qux's inner type should be union")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_optional_constraints.py b/components/script/dom/bindings/codegen/parser/tests/test_optional_constraints.py
deleted file mode 100644
index 2044c6362c3..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_optional_constraints.py
+++ /dev/null
@@ -1,35 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface OptionalConstraints1 {
-              undefined foo(optional byte arg1, byte arg2);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        not threw,
-        "Should not have thrown on non-optional argument following "
-        "optional argument.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface OptionalConstraints2 {
-          undefined foo(optional byte arg1 = 1, optional byte arg2 = 2,
-                        optional byte arg3, optional byte arg4 = 4,
-                        optional byte arg5, optional byte arg6 = 9);
-        };
-    """
-    )
-    results = parser.finish()
-    args = results[0].members[0].signatures()[0][1]
-    harness.check(len(args), 6, "Should have 6 arguments")
-    harness.check(args[5].defaultValue.value, 9, "Should have correct default value")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_overload.py b/components/script/dom/bindings/codegen/parser/tests/test_overload.py
deleted file mode 100644
index 7816276aa6d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_overload.py
+++ /dev/null
@@ -1,74 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestOverloads {
-          undefined basic();
-          undefined basic(long arg1);
-          boolean abitharder(TestOverloads foo);
-          boolean abitharder(boolean foo);
-          undefined abitharder(ArrayBuffer? foo);
-          undefined withVariadics(long... numbers);
-          undefined withVariadics(TestOverloads iface);
-          undefined withVariadics(long num, TestOverloads iface);
-          undefined optionalTest();
-          undefined optionalTest(optional long num1, long num2);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestOverloads interface parsed without error.")
-    harness.check(len(results), 1, "Should be one production.")
-    iface = results[0]
-    harness.ok(isinstance(iface, WebIDL.IDLInterface), "Should be an IDLInterface")
-    harness.check(
-        iface.identifier.QName(), "::TestOverloads", "Interface has the right QName"
-    )
-    harness.check(
-        iface.identifier.name, "TestOverloads", "Interface has the right name"
-    )
-    harness.check(len(iface.members), 4, "Expect %s members" % 4)
-
-    member = iface.members[0]
-    harness.check(
-        member.identifier.QName(),
-        "::TestOverloads::basic",
-        "Method has the right QName",
-    )
-    harness.check(member.identifier.name, "basic", "Method has the right name")
-    harness.check(member.hasOverloads(), True, "Method has overloads")
-
-    signatures = member.signatures()
-    harness.check(len(signatures), 2, "Method should have 2 signatures")
-
-    (retval, argumentSet) = signatures[0]
-
-    harness.check(str(retval), "Undefined", "Expect an undefined retval")
-    harness.check(len(argumentSet), 0, "Expect an empty argument set")
-
-    (retval, argumentSet) = signatures[1]
-    harness.check(str(retval), "Undefined", "Expect an undefined retval")
-    harness.check(len(argumentSet), 1, "Expect an argument set with one argument")
-
-    argument = argumentSet[0]
-    harness.ok(isinstance(argument, WebIDL.IDLArgument), "Should be an IDLArgument")
-    harness.check(
-        argument.identifier.QName(),
-        "::TestOverloads::basic::arg1",
-        "Argument has the right QName",
-    )
-    harness.check(argument.identifier.name, "arg1", "Argument has the right name")
-    harness.check(str(argument.type), "Long", "Argument has the right type")
-
-    member = iface.members[3]
-    harness.check(
-        len(member.overloadsForArgCount(0)), 1, "Only one overload for no args"
-    )
-    harness.check(len(member.overloadsForArgCount(1)), 0, "No overloads for one arg")
-    harness.check(
-        len(member.overloadsForArgCount(2)), 1, "Only one overload for two args"
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_promise.py b/components/script/dom/bindings/codegen/parser/tests/test_promise.py
deleted file mode 100644
index 9b418d51afe..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_promise.py
+++ /dev/null
@@ -1,177 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              legacycaller Promise<any> foo();
-            };
-        """
-        )
-        results = parser.finish()
-
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow Promise return values for legacycaller.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              Promise<any> foo();
-              long foo(long arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow overloads which have both Promise and "
-        "non-Promise return types.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              long foo(long arg);
-              Promise<any> foo();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow overloads which have both Promise and "
-        "non-Promise return types.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              Promise<any>? foo();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow nullable Promise return values.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              undefined foo(Promise<any>? arg);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow nullable Promise arguments.")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface A {
-          Promise<any> foo();
-          Promise<any> foo(long arg);
-        };
-    """
-    )
-    results = parser.finish()
-
-    harness.ok(
-        True, "Should allow overloads which only have Promise and return " "types."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              attribute Promise<any> attr;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow writable Promise-typed attributes.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              [LegacyLenientSetter] readonly attribute Promise<any> attr;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "Should not allow [LegacyLenientSetter] Promise-typed attributes."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              [PutForwards=bar] readonly attribute Promise<any> attr;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow [PutForwards] Promise-typed attributes.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              [Replaceable] readonly attribute Promise<any> attr;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow [Replaceable] Promise-typed attributes.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface A {
-              [SameObject] readonly attribute Promise<any> attr;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow [SameObject] Promise-typed attributes.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_prototype_ident.py b/components/script/dom/bindings/codegen/parser/tests/test_prototype_ident.py
deleted file mode 100644
index 5a806bf2a2d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_prototype_ident.py
+++ /dev/null
@@ -1,107 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestIface {
-              static attribute boolean prototype;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "The identifier of a static attribute must not be 'prototype'")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestIface {
-              static boolean prototype();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "The identifier of a static operation must not be 'prototype'")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestIface {
-              const boolean prototype = true;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "The identifier of a constant must not be 'prototype'")
-
-    # Make sure that we can parse non-static attributes with 'prototype' as identifier.
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestIface {
-          attribute boolean prototype;
-        };
-    """
-    )
-    results = parser.finish()
-
-    testIface = results[0]
-    harness.check(
-        testIface.members[0].isStatic(), False, "Attribute should not be static"
-    )
-    harness.check(
-        testIface.members[0].identifier.name,
-        "prototype",
-        "Attribute identifier should be 'prototype'",
-    )
-
-    # Make sure that we can parse non-static operations with 'prototype' as identifier.
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestIface {
-          boolean prototype();
-        };
-    """
-    )
-    results = parser.finish()
-
-    testIface = results[0]
-    harness.check(
-        testIface.members[0].isStatic(), False, "Operation should not be static"
-    )
-    harness.check(
-        testIface.members[0].identifier.name,
-        "prototype",
-        "Operation identifier should be 'prototype'",
-    )
-
-    # Make sure that we can parse dictionary members with 'prototype' as identifier.
-    parser = parser.reset()
-    parser.parse(
-        """
-        dictionary TestDict {
-          boolean prototype;
-        };
-    """
-    )
-    results = parser.finish()
-
-    testDict = results[0]
-    harness.check(
-        testDict.members[0].identifier.name,
-        "prototype",
-        "Dictionary member should be 'prototype'",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_putForwards.py b/components/script/dom/bindings/codegen/parser/tests/test_putForwards.py
deleted file mode 100644
index 5ec4dde280e..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_putForwards.py
+++ /dev/null
@@ -1,119 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface I {
-              [PutForwards=B] readonly attribute long A;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface I {
-              [PutForwards=B] readonly attribute J A;
-            };
-            interface J {
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface I {
-              [PutForwards=B] attribute J A;
-            };
-            interface J {
-              attribute long B;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface I {
-              [PutForwards=B] static readonly attribute J A;
-            };
-            interface J {
-              attribute long B;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            callback interface I {
-              [PutForwards=B] readonly attribute J A;
-            };
-            interface J {
-              attribute long B;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface I {
-              [PutForwards=C] readonly attribute J A;
-              [PutForwards=C] readonly attribute J B;
-            };
-            interface J {
-              [PutForwards=D] readonly attribute K C;
-            };
-            interface K {
-              [PutForwards=A] readonly attribute I D;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_record.py b/components/script/dom/bindings/codegen/parser/tests/test_record.py
deleted file mode 100644
index 3a31d721b27..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_record.py
+++ /dev/null
@@ -1,61 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        dictionary Dict {};
-        interface RecordArg {
-          undefined foo(record<DOMString, Dict> arg);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 2, "Should know about two things")
-    harness.ok(
-        isinstance(results[1], WebIDL.IDLInterface), "Should have an interface here"
-    )
-    members = results[1].members
-    harness.check(len(members), 1, "Should have one member")
-    harness.ok(members[0].isMethod(), "Should have method")
-    signature = members[0].signatures()[0]
-    args = signature[1]
-    harness.check(len(args), 1, "Should have one arg")
-    harness.ok(args[0].type.isRecord(), "Should have a record type here")
-    harness.ok(args[0].type.inner.isDictionary(), "Should have a dictionary inner type")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface RecordUndefinedArg {
-              undefined foo(record<DOMString, undefined> arg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw, "Should have thrown because record can't have undefined as value type."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            dictionary Dict {
-              record<DOMString, Dict> val;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown on dictionary containing itself via record.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_replaceable.py b/components/script/dom/bindings/codegen/parser/tests/test_replaceable.py
deleted file mode 100644
index 06ea6a47239..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_replaceable.py
+++ /dev/null
@@ -1,84 +0,0 @@
-# This Source Code Form is subject to the terms of the Mozilla Public
-# License, v. 2.0. If a copy of the MPL was not distributed with this
-# file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-
-def should_throw(parser, harness, message, code):
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(code)
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown: %s" % message)
-
-
-def WebIDLTest(parser, harness):
-    # The [Replaceable] extended attribute MUST take no arguments.
-    should_throw(
-        parser,
-        harness,
-        "no arguments",
-        """
-        interface I {
-          [Replaceable=X] readonly attribute long A;
-        };
-    """,
-    )
-
-    # An attribute with the [Replaceable] extended attribute MUST NOT also be
-    # declared with the [PutForwards] extended attribute.
-    should_throw(
-        parser,
-        harness,
-        "PutForwards",
-        """
-        interface I {
-          [PutForwards=B, Replaceable] readonly attribute J A;
-        };
-        interface J {
-          attribute long B;
-        };
-    """,
-    )
-
-    # The [Replaceable] extended attribute MUST NOT be used on an attribute
-    # that is not read only.
-    should_throw(
-        parser,
-        harness,
-        "writable attribute",
-        """
-        interface I {
-          [Replaceable] attribute long A;
-        };
-    """,
-    )
-
-    # The [Replaceable] extended attribute MUST NOT be used on a static
-    # attribute.
-    should_throw(
-        parser,
-        harness,
-        "static attribute",
-        """
-        interface I {
-          [Replaceable] static readonly attribute long A;
-        };
-    """,
-    )
-
-    # The [Replaceable] extended attribute MUST NOT be used on an attribute
-    # declared on a callback interface.
-    should_throw(
-        parser,
-        harness,
-        "callback interface",
-        """
-        callback interface I {
-          [Replaceable] readonly attribute long A;
-        };
-    """,
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_sanity.py b/components/script/dom/bindings/codegen/parser/tests/test_sanity.py
deleted file mode 100644
index d3184c00731..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_sanity.py
+++ /dev/null
@@ -1,7 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse("")
-    parser.finish()
-    harness.ok(True, "Parsing nothing doesn't throw.")
-    parser.parse("interface Foo {};")
-    parser.finish()
-    harness.ok(True, "Parsing a silly interface doesn't throw.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_securecontext_extended_attribute.py b/components/script/dom/bindings/codegen/parser/tests/test_securecontext_extended_attribute.py
deleted file mode 100644
index e0e967dd420..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_securecontext_extended_attribute.py
+++ /dev/null
@@ -1,499 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        [SecureContext]
-        interface TestSecureContextOnInterface {
-          const octet TEST_CONSTANT = 0;
-          readonly attribute byte testAttribute;
-          undefined testMethod(byte foo);
-        };
-        partial interface TestSecureContextOnInterface {
-          const octet TEST_CONSTANT_2 = 0;
-          readonly attribute byte testAttribute2;
-          undefined testMethod2(byte foo);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        6,
-        "TestSecureContextOnInterface should have six members",
-    )
-    harness.ok(
-        results[0].getExtendedAttribute("SecureContext"),
-        "Interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to constant members",
-    )
-    harness.ok(
-        results[0].members[1].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to attribute members",
-    )
-    harness.ok(
-        results[0].members[2].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to method members",
-    )
-    harness.ok(
-        results[0].members[3].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to constant members from partial interface",
-    )
-    harness.ok(
-        results[0].members[4].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to attribute members from partial interface",
-    )
-    harness.ok(
-        results[0].members[5].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to method members from partial interface",
-    )
-
-    # Same thing, but with the partial interface specified first:
-    parser = parser.reset()
-    parser.parse(
-        """
-        partial interface TestSecureContextOnInterfaceAfterPartialInterface {
-          const octet TEST_CONSTANT_2 = 0;
-          readonly attribute byte testAttribute2;
-          undefined testMethod2(byte foo);
-        };
-        [SecureContext]
-        interface TestSecureContextOnInterfaceAfterPartialInterface {
-          const octet TEST_CONSTANT = 0;
-          readonly attribute byte testAttribute;
-          undefined testMethod(byte foo);
-        };
-     """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[1].members),
-        6,
-        "TestSecureContextOnInterfaceAfterPartialInterface should have six members",
-    )
-    harness.ok(
-        results[1].getExtendedAttribute("SecureContext"),
-        "Interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[1].members[0].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to constant members",
-    )
-    harness.ok(
-        results[1].members[1].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to attribute members",
-    )
-    harness.ok(
-        results[1].members[2].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to method members",
-    )
-    harness.ok(
-        results[1].members[3].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to constant members from partial interface",
-    )
-    harness.ok(
-        results[1].members[4].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to attribute members from partial interface",
-    )
-    harness.ok(
-        results[1].members[5].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to method members from partial interface",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestSecureContextOnPartialInterface {
-          const octet TEST_CONSTANT = 0;
-          readonly attribute byte testAttribute;
-          undefined testMethod(byte foo);
-        };
-        [SecureContext]
-        partial interface TestSecureContextOnPartialInterface {
-          const octet TEST_CONSTANT_2 = 0;
-          readonly attribute byte testAttribute2;
-          undefined testMethod2(byte foo);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        6,
-        "TestSecureContextOnPartialInterface should have six members",
-    )
-    harness.ok(
-        results[0].getExtendedAttribute("SecureContext") is None,
-        "[SecureContext] should not propagate from a partial interface to the interface",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext") is None,
-        "[SecureContext] should not propagate from a partial interface to the interface's constant members",
-    )
-    harness.ok(
-        results[0].members[1].getExtendedAttribute("SecureContext") is None,
-        "[SecureContext] should not propagate from a partial interface to the interface's attribute members",
-    )
-    harness.ok(
-        results[0].members[2].getExtendedAttribute("SecureContext") is None,
-        "[SecureContext] should not propagate from a partial interface to the interface's method members",
-    )
-    harness.ok(
-        results[0].members[3].getExtendedAttribute("SecureContext"),
-        "Constant members from [SecureContext] partial interface should be [SecureContext]",
-    )
-    harness.ok(
-        results[0].members[4].getExtendedAttribute("SecureContext"),
-        "Attribute members from [SecureContext] partial interface should be [SecureContext]",
-    )
-    harness.ok(
-        results[0].members[5].getExtendedAttribute("SecureContext"),
-        "Method members from [SecureContext] partial interface should be [SecureContext]",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestSecureContextOnInterfaceMembers {
-          const octet TEST_NON_SECURE_CONSTANT_1 = 0;
-          [SecureContext]
-          const octet TEST_SECURE_CONSTANT       = 1;
-          const octet TEST_NON_SECURE_CONSTANT_2 = 2;
-          readonly attribute byte testNonSecureAttribute1;
-          [SecureContext]
-          readonly attribute byte testSecureAttribute;
-          readonly attribute byte testNonSecureAttribute2;
-          undefined testNonSecureMethod1(byte foo);
-          [SecureContext]
-          undefined testSecureMethod(byte foo);
-          undefined testNonSecureMethod2(byte foo);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        9,
-        "TestSecureContextOnInterfaceMembers should have nine members",
-    )
-    harness.ok(
-        results[0].getExtendedAttribute("SecureContext") is None,
-        "[SecureContext] on members should not propagate up to the interface",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext") is None,
-        "Constant should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[1].getExtendedAttribute("SecureContext"),
-        "Constant should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[2].getExtendedAttribute("SecureContext") is None,
-        "Constant should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[3].getExtendedAttribute("SecureContext") is None,
-        "Attribute should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[4].getExtendedAttribute("SecureContext"),
-        "Attribute should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[5].getExtendedAttribute("SecureContext") is None,
-        "Attribute should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[6].getExtendedAttribute("SecureContext") is None,
-        "Method should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[7].getExtendedAttribute("SecureContext"),
-        "Method should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[8].getExtendedAttribute("SecureContext") is None,
-        "Method should not have [SecureContext] extended attribute",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestSecureContextOnPartialInterfaceMembers {
-        };
-        partial interface TestSecureContextOnPartialInterfaceMembers {
-          const octet TEST_NON_SECURE_CONSTANT_1 = 0;
-          [SecureContext]
-          const octet TEST_SECURE_CONSTANT       = 1;
-          const octet TEST_NON_SECURE_CONSTANT_2 = 2;
-          readonly attribute byte testNonSecureAttribute1;
-          [SecureContext]
-          readonly attribute byte testSecureAttribute;
-          readonly attribute byte testNonSecureAttribute2;
-          undefined testNonSecureMethod1(byte foo);
-          [SecureContext]
-          undefined testSecureMethod(byte foo);
-          undefined testNonSecureMethod2(byte foo);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        9,
-        "TestSecureContextOnPartialInterfaceMembers should have nine members",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext") is None,
-        "Constant from partial interface should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[1].getExtendedAttribute("SecureContext"),
-        "Constant from partial interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[2].getExtendedAttribute("SecureContext") is None,
-        "Constant from partial interface should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[3].getExtendedAttribute("SecureContext") is None,
-        "Attribute from partial interface should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[4].getExtendedAttribute("SecureContext"),
-        "Attribute from partial interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[5].getExtendedAttribute("SecureContext") is None,
-        "Attribute from partial interface should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[6].getExtendedAttribute("SecureContext") is None,
-        "Method from partial interface should not have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[7].getExtendedAttribute("SecureContext"),
-        "Method from partial interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[8].getExtendedAttribute("SecureContext") is None,
-        "Method from partial interface should not have [SecureContext] extended attribute",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SecureContext=something]
-            interface TestSecureContextTakesNoValue1 {
-              const octet TEST_SECURE_CONSTANT = 0;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "[SecureContext] must take no arguments (testing on interface)")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestSecureContextForOverloads1 {
-              [SecureContext]
-              undefined testSecureMethod(byte foo);
-            };
-            partial interface TestSecureContextForOverloads1 {
-              undefined testSecureMethod(byte foo, byte bar);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "If [SecureContext] appears on an overloaded operation, then it MUST appear on all overloads",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestSecureContextForOverloads2 {
-              [SecureContext]
-              undefined testSecureMethod(byte foo);
-            };
-            partial interface TestSecureContextForOverloads2 {
-              [SecureContext]
-              undefined testSecureMethod(byte foo, byte bar);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        not threw,
-        "[SecureContext] can appear on an overloaded operation if it appears on all overloads",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SecureContext]
-            interface TestSecureContextOnInterfaceAndMember {
-              [SecureContext]
-              undefined testSecureMethod(byte foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw, "[SecureContext] must not appear on an interface and interface member"
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestSecureContextOnPartialInterfaceAndMember {
-            };
-            [SecureContext]
-            partial interface TestSecureContextOnPartialInterfaceAndMember {
-              [SecureContext]
-              undefined testSecureMethod(byte foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "[SecureContext] must not appear on a partial interface and one of the partial interface's member's",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SecureContext]
-            interface TestSecureContextOnInterfaceAndPartialInterfaceMember {
-            };
-            partial interface TestSecureContextOnInterfaceAndPartialInterfaceMember {
-              [SecureContext]
-              undefined testSecureMethod(byte foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "[SecureContext] must not appear on an interface and one of its partial interface's member's",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [SecureContext]
-            interface TestSecureContextOnInheritedInterface {
-            };
-            interface TestSecureContextNotOnInheritingInterface : TestSecureContextOnInheritedInterface {
-              undefined testSecureMethod(byte foo);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "[SecureContext] must appear on interfaces that inherit from another [SecureContext] interface",
-    )
-
-    # Test 'includes'.
-    parser = parser.reset()
-    parser.parse(
-        """
-        [SecureContext]
-        interface TestSecureContextInterfaceThatIncludesNonSecureContextMixin {
-          const octet TEST_CONSTANT = 0;
-        };
-        interface mixin TestNonSecureContextMixin {
-          const octet TEST_CONSTANT_2 = 0;
-          readonly attribute byte testAttribute2;
-          undefined testMethod2(byte foo);
-        };
-        TestSecureContextInterfaceThatIncludesNonSecureContextMixin includes TestNonSecureContextMixin;
-     """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        4,
-        "TestSecureContextInterfaceThatImplementsNonSecureContextInterface should have four members",
-    )
-    harness.ok(
-        results[0].getExtendedAttribute("SecureContext"),
-        "Interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext"),
-        "[SecureContext] should propagate from interface to constant members even when other members are copied from a non-[SecureContext] interface",
-    )
-    harness.ok(
-        results[0].members[1].getExtendedAttribute("SecureContext") is None,
-        "Constants copied from non-[SecureContext] mixin should not be [SecureContext]",
-    )
-    harness.ok(
-        results[0].members[2].getExtendedAttribute("SecureContext") is None,
-        "Attributes copied from non-[SecureContext] mixin should not be [SecureContext]",
-    )
-    harness.ok(
-        results[0].members[3].getExtendedAttribute("SecureContext") is None,
-        "Methods copied from non-[SecureContext] mixin should not be [SecureContext]",
-    )
-
-    # Test SecureContext and LegacyNoInterfaceObject
-    parser = parser.reset()
-    parser.parse(
-        """
-        [LegacyNoInterfaceObject, SecureContext]
-        interface TestSecureContextLegacyNoInterfaceObject {
-          undefined testSecureMethod(byte foo);
-        };
-    """
-    )
-    results = parser.finish()
-    harness.check(
-        len(results[0].members),
-        1,
-        "TestSecureContextLegacyNoInterfaceObject should have only one member",
-    )
-    harness.ok(
-        results[0].getExtendedAttribute("SecureContext"),
-        "Interface should have [SecureContext] extended attribute",
-    )
-    harness.ok(
-        results[0].members[0].getExtendedAttribute("SecureContext"),
-        "Interface member should have [SecureContext] extended attribute",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_special_method_signature_mismatch.py b/components/script/dom/bindings/codegen/parser/tests/test_special_method_signature_mismatch.py
deleted file mode 100644
index a11860b3728..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_special_method_signature_mismatch.py
+++ /dev/null
@@ -1,256 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch1 {
-              getter long long foo(long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch2 {
-              getter undefined foo(unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch3 {
-              getter boolean foo(unsigned long index, boolean extraArg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch4 {
-              getter boolean foo(unsigned long... index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch5 {
-              getter boolean foo(optional unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch6 {
-              getter boolean foo();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch7 {
-              deleter long long foo(long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch9 {
-              deleter boolean foo(unsigned long index, boolean extraArg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch10 {
-              deleter boolean foo(unsigned long... index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch11 {
-              deleter boolean foo(optional unsigned long index);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch12 {
-              deleter boolean foo();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch13 {
-              setter long long foo(long index, long long value);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch15 {
-              setter boolean foo(unsigned long index, boolean value, long long extraArg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch16 {
-              setter boolean foo(unsigned long index, boolean... value);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch17 {
-              setter boolean foo(unsigned long index, optional boolean value);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodSignatureMismatch18 {
-              setter boolean foo();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_special_methods.py b/components/script/dom/bindings/codegen/parser/tests/test_special_methods.py
deleted file mode 100644
index 9601a0a968f..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_special_methods.py
+++ /dev/null
@@ -1,117 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface SpecialMethods {
-          getter long long (unsigned long index);
-          setter long long (unsigned long index, long long value);
-          getter boolean (DOMString name);
-          setter boolean (DOMString name, boolean value);
-          deleter boolean (DOMString name);
-          readonly attribute unsigned long length;
-        };
-
-        interface SpecialMethodsCombination {
-          getter deleter boolean (DOMString name);
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    def checkMethod(
-        method,
-        QName,
-        name,
-        static=False,
-        getter=False,
-        setter=False,
-        deleter=False,
-        legacycaller=False,
-        stringifier=False,
-    ):
-        harness.ok(isinstance(method, WebIDL.IDLMethod), "Should be an IDLMethod")
-        harness.check(method.identifier.QName(), QName, "Method has the right QName")
-        harness.check(method.identifier.name, name, "Method has the right name")
-        harness.check(method.isStatic(), static, "Method has the correct static value")
-        harness.check(method.isGetter(), getter, "Method has the correct getter value")
-        harness.check(method.isSetter(), setter, "Method has the correct setter value")
-        harness.check(
-            method.isDeleter(), deleter, "Method has the correct deleter value"
-        )
-        harness.check(
-            method.isLegacycaller(),
-            legacycaller,
-            "Method has the correct legacycaller value",
-        )
-        harness.check(
-            method.isStringifier(),
-            stringifier,
-            "Method has the correct stringifier value",
-        )
-
-    harness.check(len(results), 2, "Expect 2 interfaces")
-
-    iface = results[0]
-    harness.check(len(iface.members), 6, "Expect 6 members")
-
-    checkMethod(
-        iface.members[0],
-        "::SpecialMethods::__indexedgetter",
-        "__indexedgetter",
-        getter=True,
-    )
-    checkMethod(
-        iface.members[1],
-        "::SpecialMethods::__indexedsetter",
-        "__indexedsetter",
-        setter=True,
-    )
-    checkMethod(
-        iface.members[2],
-        "::SpecialMethods::__namedgetter",
-        "__namedgetter",
-        getter=True,
-    )
-    checkMethod(
-        iface.members[3],
-        "::SpecialMethods::__namedsetter",
-        "__namedsetter",
-        setter=True,
-    )
-    checkMethod(
-        iface.members[4],
-        "::SpecialMethods::__nameddeleter",
-        "__nameddeleter",
-        deleter=True,
-    )
-
-    iface = results[1]
-    harness.check(len(iface.members), 1, "Expect 1 member")
-
-    checkMethod(
-        iface.members[0],
-        "::SpecialMethodsCombination::__namedgetterdeleter",
-        "__namedgetterdeleter",
-        getter=True,
-        deleter=True,
-    )
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface IndexedDeleter {
-              deleter undefined(unsigned long index);
-            };
-            """
-        )
-        parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "There are no indexed deleters")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_special_methods_uniqueness.py b/components/script/dom/bindings/codegen/parser/tests/test_special_methods_uniqueness.py
deleted file mode 100644
index 014737e8168..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_special_methods_uniqueness.py
+++ /dev/null
@@ -1,54 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodUniqueness1 {
-              getter deleter boolean (DOMString name);
-              getter boolean (DOMString name);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodUniqueness1 {
-              deleter boolean (DOMString name);
-              getter deleter boolean (DOMString name);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface SpecialMethodUniqueness1 {
-              setter boolean (DOMString name);
-              setter boolean (DOMString name);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_stringifier.py b/components/script/dom/bindings/codegen/parser/tests/test_stringifier.py
deleted file mode 100644
index 948be71e4dd..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_stringifier.py
+++ /dev/null
@@ -1,196 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestStringifier {
-          stringifier;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(
-        isinstance(results[0].members[0], WebIDL.IDLMethod),
-        "Stringifer should be method",
-    )
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestStringifier {
-              stringifier;
-              stringifier;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow two 'stringifier;'")
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestStringifier {
-              stringifier;
-              stringifier DOMString foo();
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow a 'stringifier;' and a 'stringifier()'")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestStringifier {
-            stringifier attribute DOMString foo;
-        };
-    """
-    )
-    results = parser.finish()
-    harness.ok(
-        isinstance(results[0].members[0], WebIDL.IDLAttribute),
-        "Stringifier attribute should be an attribute",
-    )
-    stringifier = results[0].members[1]
-    harness.ok(
-        isinstance(stringifier, WebIDL.IDLMethod),
-        "Stringifier attribute should insert a method",
-    )
-    harness.ok(stringifier.isStringifier(), "Inserted method should be a stringifier")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestStringifier {};
-        interface mixin TestStringifierMixin {
-            stringifier attribute DOMString foo;
-        };
-        TestStringifier includes TestStringifierMixin;
-    """
-    )
-    results = parser.finish()
-    harness.ok(
-        isinstance(results[0].members[0], WebIDL.IDLAttribute),
-        "Stringifier attribute should be an attribute",
-    )
-    stringifier = results[0].members[1]
-    harness.ok(
-        isinstance(stringifier, WebIDL.IDLMethod),
-        "Stringifier attribute should insert a method",
-    )
-    harness.ok(stringifier.isStringifier(), "Inserted method should be a stringifier")
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestStringifier {
-            stringifier attribute USVString foo;
-        };
-    """
-    )
-    results = parser.finish()
-    stringifier = results[0].members[1]
-    harness.ok(
-        stringifier.signatures()[0][0].isUSVString(),
-        "Stringifier attributes should allow USVString",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestStringifier {
-            [Throws, NeedsSubjectPrincipal]
-            stringifier attribute USVString foo;
-        };
-    """
-    )
-    results = parser.finish()
-    stringifier = results[0].members[1]
-    harness.ok(
-        stringifier.getExtendedAttribute("Throws"),
-        "Stringifier attributes should support [Throws]",
-    )
-    harness.ok(
-        stringifier.getExtendedAttribute("NeedsSubjectPrincipal"),
-        "Stringifier attributes should support [NeedsSubjectPrincipal]",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface TestStringifier {
-            stringifier attribute UTF8String foo;
-        };
-    """
-    )
-    results = parser.finish()
-    stringifier = results[0].members[1]
-    harness.ok(
-        stringifier.signatures()[0][0].isUTF8String(),
-        "Stringifier attributes should allow UTF8String",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestStringifier {
-              stringifier attribute ByteString foo;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow ByteString")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestStringifier {
-              stringifier;
-              stringifier attribute DOMString foo;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow a 'stringifier;' and a stringifier attribute")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface TestStringifier {
-              stringifier attribute DOMString foo;
-              stringifier attribute DOMString bar;
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should not allow multiple stringifier attributes")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_toJSON.py b/components/script/dom/bindings/codegen/parser/tests/test_toJSON.py
deleted file mode 100644
index f312667ec4d..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_toJSON.py
+++ /dev/null
@@ -1,309 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              object toJSON();
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(not threw, "Should allow a toJSON method.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              object toJSON(object arg);
-              object toJSON(long arg);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow overloads of a toJSON method.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              object toJSON(object arg);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(threw, "Should not allow a toJSON method with arguments.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              long toJSON();
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(not threw, "Should allow a toJSON method with 'long' as return type.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              [Default] object toJSON();
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        not threw, "Should allow a default toJSON method with 'object' as return type."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Test {
-              [Default] long toJSON();
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should not allow a default toJSON method with non-'object' as return type.",
-    )
-
-    JsonTypes = [
-        "byte",
-        "octet",
-        "short",
-        "unsigned short",
-        "long",
-        "unsigned long",
-        "long long",
-        "unsigned long long",
-        "float",
-        "unrestricted float",
-        "double",
-        "unrestricted double",
-        "boolean",
-        "DOMString",
-        "ByteString",
-        "UTF8String",
-        "USVString",
-        "Enum",
-        "InterfaceWithToJSON",
-        "object",
-    ]
-
-    nonJsonTypes = [
-        "InterfaceWithoutToJSON",
-        "any",
-        "Int8Array",
-        "Int16Array",
-        "Int32Array",
-        "Uint8Array",
-        "Uint16Array",
-        "Uint32Array",
-        "Uint8ClampedArray",
-        "Float32Array",
-        "Float64Array",
-        "ArrayBuffer",
-    ]
-
-    def doTest(testIDL, shouldThrow, description):
-        p = parser.reset()
-        threw = False
-        try:
-            p.parse(
-                testIDL
-                + """
-                enum Enum { "a", "b", "c" };
-                interface InterfaceWithToJSON { long toJSON(); };
-                interface InterfaceWithoutToJSON {};
-                """
-            )
-            p.finish()
-        except Exception as x:
-            threw = True
-            harness.ok(x.message == "toJSON method has non-JSON return type", x)
-        harness.check(threw, shouldThrow, description)
-
-    for type in JsonTypes:
-        doTest(
-            "interface Test { %s toJSON(); };" % type,
-            False,
-            "%s should be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { sequence<%s> toJSON(); };" % type,
-            False,
-            "sequence<%s> should be a JSON type" % type,
-        )
-
-        doTest(
-            "dictionary Foo { %s foo; }; " "interface Test { Foo toJSON(); }; " % type,
-            False,
-            "dictionary containing only JSON type (%s) should be a JSON type" % type,
-        )
-
-        doTest(
-            "dictionary Foo { %s foo; }; dictionary Bar : Foo { }; "
-            "interface Test { Bar toJSON(); }; " % type,
-            False,
-            "dictionary whose ancestors only contain JSON types should be a JSON type",
-        )
-
-        doTest(
-            "dictionary Foo { any foo; }; dictionary Bar : Foo { %s bar; };"
-            "interface Test { Bar toJSON(); };" % type,
-            True,
-            "dictionary whose ancestors contain non-JSON types should not be a JSON type",
-        )
-
-        doTest(
-            "interface Test { record<DOMString, %s> toJSON(); };" % type,
-            False,
-            "record<DOMString, %s> should be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { record<ByteString, %s> toJSON(); };" % type,
-            False,
-            "record<ByteString, %s> should be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { record<UTF8String, %s> toJSON(); };" % type,
-            False,
-            "record<UTF8String, %s> should be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { record<USVString, %s> toJSON(); };" % type,
-            False,
-            "record<USVString, %s> should be a JSON type" % type,
-        )
-
-        otherUnionType = "Foo" if type != "object" else "long"
-        doTest(
-            "interface Foo { object toJSON(); };"
-            "interface Test { (%s or %s) toJSON(); };" % (otherUnionType, type),
-            False,
-            "union containing only JSON types (%s or %s) should be a JSON type"
-            % (otherUnionType, type),
-        )
-
-        doTest(
-            "interface test { %s? toJSON(); };" % type,
-            False,
-            "Nullable type (%s) should be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Foo : InterfaceWithoutToJSON { %s toJSON(); };"
-            "interface Test { Foo toJSON(); };" % type,
-            False,
-            "interface with toJSON should be a JSON type",
-        )
-
-    doTest(
-        "interface Foo : InterfaceWithToJSON { };" "interface Test { Foo toJSON(); };",
-        False,
-        "inherited interface with toJSON should be a JSON type",
-    )
-
-    for type in nonJsonTypes:
-        doTest(
-            "interface Test { %s toJSON(); };" % type,
-            True,
-            "%s should not be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { sequence<%s> toJSON(); };" % type,
-            True,
-            "sequence<%s> should not be a JSON type" % type,
-        )
-
-        doTest(
-            "dictionary Foo { %s foo; }; " "interface Test { Foo toJSON(); }; " % type,
-            True,
-            "Dictionary containing a non-JSON type (%s) should not be a JSON type"
-            % type,
-        )
-
-        doTest(
-            "dictionary Foo { %s foo; }; dictionary Bar : Foo { }; "
-            "interface Test { Bar toJSON(); }; " % type,
-            True,
-            "dictionary whose ancestors only contain non-JSON types should not be a JSON type",
-        )
-
-        doTest(
-            "interface Test { record<DOMString, %s> toJSON(); };" % type,
-            True,
-            "record<DOMString, %s> should not be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { record<ByteString, %s> toJSON(); };" % type,
-            True,
-            "record<ByteString, %s> should not be a JSON type" % type,
-        )
-
-        doTest(
-            "interface Test { record<USVString, %s> toJSON(); };" % type,
-            True,
-            "record<USVString, %s> should not be a JSON type" % type,
-        )
-
-        if type != "any":
-            doTest(
-                "interface Foo { object toJSON(); }; "
-                "interface Test { (Foo or %s) toJSON(); };" % type,
-                True,
-                "union containing a non-JSON type (%s) should not be a JSON type"
-                % type,
-            )
-
-            doTest(
-                "interface test { %s? toJSON(); };" % type,
-                True,
-                "Nullable type (%s) should not be a JSON type" % type,
-            )
-
-    doTest(
-        "dictionary Foo { long foo; any bar; };" "interface Test { Foo toJSON(); };",
-        True,
-        "dictionary containing a non-JSON type should not be a JSON type",
-    )
-
-    doTest(
-        "interface Foo : InterfaceWithoutToJSON { }; "
-        "interface Test { Foo toJSON(); };",
-        True,
-        "interface without toJSON should not be a JSON type",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_treatNonCallableAsNull.py b/components/script/dom/bindings/codegen/parser/tests/test_treatNonCallableAsNull.py
deleted file mode 100644
index 7becfdca1f3..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_treatNonCallableAsNull.py
+++ /dev/null
@@ -1,80 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        [TreatNonCallableAsNull] callback Function = any(any... arguments);
-
-        interface TestTreatNonCallableAsNull1 {
-          attribute Function? onfoo;
-          attribute Function onbar;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    iface = results[1]
-    attr = iface.members[0]
-    harness.check(attr.type.treatNonCallableAsNull(), True, "Got the expected value")
-    attr = iface.members[1]
-    harness.check(attr.type.treatNonCallableAsNull(), False, "Got the expected value")
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            callback Function = any(any... arguments);
-
-            interface TestTreatNonCallableAsNull2 {
-              [TreatNonCallableAsNull] attribute Function onfoo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            callback Function = any(any... arguments);
-
-            [TreatNonCallableAsNull]
-            interface TestTreatNonCallableAsNull3 {
-               attribute Function onfoo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-
-    threw = False
-    try:
-        parser.parse(
-            """
-            [TreatNonCallableAsNull, LegacyTreatNonObjectAsNull]
-            callback Function = any(any... arguments);
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_typedef.py b/components/script/dom/bindings/codegen/parser/tests/test_typedef.py
deleted file mode 100644
index c19d064efff..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_typedef.py
+++ /dev/null
@@ -1,94 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-      typedef long mylong;
-      typedef long? mynullablelong;
-      interface Foo {
-        const mylong X = 5;
-        undefined foo(optional mynullablelong arg = 7);
-        undefined bar(optional mynullablelong arg = null);
-        undefined baz(mylong arg);
-      };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(
-        results[2].members[1].signatures()[0][1][0].type.name,
-        "LongOrNull",
-        "Should expand typedefs",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          typedef long? mynullablelong;
-          interface Foo {
-            undefined foo(mynullablelong? Y);
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on nullable inside nullable arg.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          typedef long? mynullablelong;
-          interface Foo {
-            const mynullablelong? X = 5;
-          };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on nullable inside nullable const.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-          interface Foo {
-            const mynullablelong? X = 5;
-          };
-          typedef long? mynullablelong;
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown on nullable inside nullable const typedef "
-        "after interface.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-      interface Foo {
-        const mylong X = 5;
-      };
-      typedef long mylong;
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(
-        results[0].members[0].type.name,
-        "Long",
-        "Should expand typedefs that come before interface",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_typedef_identifier_conflict.py b/components/script/dom/bindings/codegen/parser/tests/test_typedef_identifier_conflict.py
deleted file mode 100644
index 2aab3a8a91f..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_typedef_identifier_conflict.py
+++ /dev/null
@@ -1,19 +0,0 @@
-def WebIDLTest(parser, harness):
-    exception = None
-    try:
-        parser.parse(
-            """
-            typedef long foo;
-            typedef long foo;
-            """
-        )
-
-        results = parser.finish()
-    except Exception as e:
-        exception = e
-
-    harness.ok(exception, "Should have thrown.")
-    harness.ok(
-        "Multiple unresolvable definitions of identifier 'foo'" in str(exception),
-        "Should have a sane exception message",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_undefined.py b/components/script/dom/bindings/codegen/parser/tests/test_undefined.py
deleted file mode 100644
index 4731ee1bcd7..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_undefined.py
+++ /dev/null
@@ -1,246 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    try:
-        parser.parse(
-            """
-            dictionary Dict {
-              undefined undefinedMember;
-              double bar;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "undefined must not be used as the type of a dictionary member")
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            dictionary Dict {
-              (undefined or double) undefinedMemberOfUnionInDict;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of a dictionary member, "
-        "whether directly or in a union",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              double bar(undefined foo);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a regular operation)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              getter double(undefined name);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a getter)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              setter undefined(DOMString name, undefined value);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a setter)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              deleter undefined (undefined name);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a deleter)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              constructor (undefined foo);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a constructor)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            callback Callback = undefined (undefined foo);
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a callback)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              async iterable(undefined name);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of an async iterable "
-        "iterator)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              static double bar(undefined foo);
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined must not be used as the type of an argument in any "
-        "circumstance (so not as the argument of a static operation)",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              const undefined FOO = undefined;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined is not a valid type for a constant",
-    )
-
-    parser = parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface Foo {
-              const any FOO = undefined;
-            };
-            """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "undefined is not a valid value for a constant",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_unenumerable_own_properties.py b/components/script/dom/bindings/codegen/parser/tests/test_unenumerable_own_properties.py
deleted file mode 100644
index b024d317492..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_unenumerable_own_properties.py
+++ /dev/null
@@ -1,71 +0,0 @@
-def WebIDLTest(parser, harness):
-
-    parser.parse(
-        """
-        interface Foo {};
-        [LegacyUnenumerableNamedProperties]
-        interface Bar : Foo {
-          getter long(DOMString name);
-        };
-        interface Baz : Bar {
-          getter long(DOMString name);
-        };
-        """
-    )
-    results = parser.finish()
-    harness.check(len(results), 3, "Should have three interfaces")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyUnenumerableNamedProperties]
-            interface NoNamedGetter {
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyUnenumerableNamedProperties=Foo]
-            interface ShouldNotHaveArg {
-              getter long(DOMString name);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            [LegacyUnenumerableNamedProperties]
-            interface Foo {
-              getter long(DOMString name);
-            };
-            interface Bar : Foo {};
-            [LegacyUnenumerableNamedProperties]
-            interface Baz : Bar {
-              getter long(DOMString name);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_unforgeable.py b/components/script/dom/bindings/codegen/parser/tests/test_unforgeable.py
deleted file mode 100644
index 500d123ddb2..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_unforgeable.py
+++ /dev/null
@@ -1,311 +0,0 @@
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-            interface Child : Parent {
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results),
-        2,
-        "Should be able to inherit from an interface with "
-        "[LegacyUnforgeable] properties.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-            interface Child : Parent {
-              const short foo = 10;
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results),
-        2,
-        "Should be able to inherit from an interface with "
-        "[LegacyUnforgeable] properties even if we have a constant with "
-        "the same name.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-            interface Child : Parent {
-              static attribute short foo;
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results),
-        2,
-        "Should be able to inherit from an interface with "
-        "[LegacyUnforgeable] properties even if we have a static attribute "
-        "with the same name.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-            interface Child : Parent {
-              static undefined foo();
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results),
-        2,
-        "Should be able to inherit from an interface with "
-        "[LegacyUnforgeable] properties even if we have a static operation "
-        "with the same name.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-              undefined foo();
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should have thrown when shadowing unforgeable attribute on "
-        "parent with operation.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-              undefined foo();
-            };
-            interface Parent {
-              [LegacyUnforgeable] undefined foo();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-    harness.ok(
-        threw,
-        "Should have thrown when shadowing unforgeable operation on "
-        "parent with operation.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-              attribute short foo;
-            };
-            interface Parent {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw,
-        "Should have thrown when shadowing unforgeable attribute on "
-        "parent with attribute.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-              attribute short foo;
-            };
-            interface Parent {
-              [LegacyUnforgeable] undefined foo();
-            };
-        """
-        )
-
-        results = parser.finish()
-    except Exception as x:
-        threw = True
-    harness.ok(
-        threw,
-        "Should have thrown when shadowing unforgeable operation on "
-        "parent with attribute.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-            interface Child : Parent {
-            };
-            interface Parent {};
-            interface mixin Mixin {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-            Parent includes Mixin;
-        """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results),
-        4,
-        "Should be able to inherit from an interface with a "
-        "mixin with [LegacyUnforgeable] properties.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-              undefined foo();
-            };
-            interface Parent {};
-            interface mixin Mixin {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-            Parent includes Mixin;
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown when shadowing unforgeable attribute "
-        "of parent's consequential interface.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-            };
-            interface Parent : GrandParent {};
-            interface GrandParent {};
-            interface mixin Mixin {
-              [LegacyUnforgeable] readonly attribute long foo;
-            };
-            GrandParent includes Mixin;
-            interface mixin ChildMixin {
-              undefined foo();
-            };
-            Child includes ChildMixin;
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown when our consequential interface shadows unforgeable attribute "
-        "of ancestor's consequential interface.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface Child : Parent {
-            };
-            interface Parent : GrandParent {};
-            interface GrandParent {};
-            interface mixin Mixin {
-              [LegacyUnforgeable] undefined foo();
-            };
-            GrandParent includes Mixin;
-            interface mixin ChildMixin {
-              undefined foo();
-            };
-            Child includes ChildMixin;
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown when our consequential interface shadows unforgeable operation "
-        "of ancestor's consequential interface.",
-    )
-
-    parser = parser.reset()
-    parser.parse(
-        """
-        interface iface {
-          [LegacyUnforgeable] attribute long foo;
-        };
-    """
-    )
-
-    results = parser.finish()
-    harness.check(
-        len(results), 1, "Should allow writable [LegacyUnforgeable] attribute."
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface iface {
-              [LegacyUnforgeable] static readonly attribute long foo;
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown for static [LegacyUnforgeable] attribute.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_union.py b/components/script/dom/bindings/codegen/parser/tests/test_union.py
deleted file mode 100644
index 7fc1236d54e..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_union.py
+++ /dev/null
@@ -1,198 +0,0 @@
-import WebIDL
-import itertools
-import string
-
-# We'd like to use itertools.chain but it's 2.6 or higher.
-
-
-def chain(*iterables):
-    # chain('ABC', 'DEF') --> A B C D E F
-    for it in iterables:
-        for element in it:
-            yield element
-
-
-# We'd like to use itertools.combinations but it's 2.6 or higher.
-def combinations(iterable, r):
-    # combinations('ABCD', 2) --> AB AC AD BC BD CD
-    # combinations(range(4), 3) --> 012 013 023 123
-    pool = tuple(iterable)
-    n = len(pool)
-    if r > n:
-        return
-    indices = list(range(r))
-    yield tuple(pool[i] for i in indices)
-    while True:
-        for i in reversed(range(r)):
-            if indices[i] != i + n - r:
-                break
-        else:
-            return
-        indices[i] += 1
-        for j in range(i + 1, r):
-            indices[j] = indices[j - 1] + 1
-        yield tuple(pool[i] for i in indices)
-
-
-# We'd like to use itertools.combinations_with_replacement but it's 2.7 or
-# higher.
-def combinations_with_replacement(iterable, r):
-    # combinations_with_replacement('ABC', 2) --> AA AB AC BB BC CC
-    pool = tuple(iterable)
-    n = len(pool)
-    if not n and r:
-        return
-    indices = [0] * r
-    yield tuple(pool[i] for i in indices)
-    while True:
-        for i in reversed(range(r)):
-            if indices[i] != n - 1:
-                break
-        else:
-            return
-        indices[i:] = [indices[i] + 1] * (r - i)
-        yield tuple(pool[i] for i in indices)
-
-
-def WebIDLTest(parser, harness):
-    types = [
-        "float",
-        "double",
-        "short",
-        "unsigned short",
-        "long",
-        "unsigned long",
-        "long long",
-        "unsigned long long",
-        "boolean",
-        "byte",
-        "octet",
-        "DOMString",
-        "ByteString",
-        "USVString",
-        # "sequence<float>",
-        "object",
-        "ArrayBuffer",
-        # "Date",
-        "TestInterface1",
-        "TestInterface2",
-    ]
-
-    testPre = """
-        interface TestInterface1 {
-        };
-        interface TestInterface2 {
-        };
-        """
-
-    interface = (
-        testPre
-        + """
-        interface PrepareForTest {
-        """
-    )
-    for (i, type) in enumerate(types):
-        interface += string.Template(
-            """
-          readonly attribute ${type} attr${i};
-        """
-        ).substitute(i=i, type=type)
-    interface += """
-        };
-        """
-
-    parser.parse(interface)
-    results = parser.finish()
-
-    iface = results[2]
-
-    parser = parser.reset()
-
-    def typesAreDistinguishable(t):
-        return all(u[0].isDistinguishableFrom(u[1]) for u in combinations(t, 2))
-
-    def typesAreNotDistinguishable(t):
-        return any(not u[0].isDistinguishableFrom(u[1]) for u in combinations(t, 2))
-
-    def unionTypeName(t):
-        if len(t) > 2:
-            t[0:2] = [unionTypeName(t[0:2])]
-        return "(" + " or ".join(t) + ")"
-
-    # typeCombinations is an iterable of tuples containing the name of the type
-    # as a string and the parsed IDL type.
-    def unionTypes(typeCombinations, predicate):
-        for c in typeCombinations:
-            if predicate(t[1] for t in c):
-                yield unionTypeName([t[0] for t in c])
-
-    # We limit invalid union types with a union member type to the subset of 3
-    # types with one invalid combination.
-    # typeCombinations is an iterable of tuples containing the name of the type
-    # as a string and the parsed IDL type.
-    def invalidUnionWithUnion(typeCombinations):
-        for c in typeCombinations:
-            if (
-                typesAreNotDistinguishable((c[0][1], c[1][1]))
-                and typesAreDistinguishable((c[1][1], c[2][1]))
-                and typesAreDistinguishable((c[0][1], c[2][1]))
-            ):
-                yield unionTypeName([t[0] for t in c])
-
-    # Create a list of tuples containing the name of the type as a string and
-    # the parsed IDL type.
-    types = zip(types, (a.type for a in iface.members))
-
-    validUnionTypes = chain(
-        unionTypes(combinations(types, 2), typesAreDistinguishable),
-        unionTypes(combinations(types, 3), typesAreDistinguishable),
-    )
-    invalidUnionTypes = chain(
-        unionTypes(combinations_with_replacement(types, 2), typesAreNotDistinguishable),
-        invalidUnionWithUnion(combinations(types, 3)),
-    )
-    interface = (
-        testPre
-        + """
-        interface TestUnion {
-        """
-    )
-    for (i, type) in enumerate(validUnionTypes):
-        interface += string.Template(
-            """
-          undefined method${i}(${type} arg);
-          ${type} returnMethod${i}();
-          attribute ${type} attr${i};
-          undefined optionalMethod${i}(${type}? arg);
-        """
-        ).substitute(i=i, type=type)
-    interface += """
-        };
-        """
-    parser.parse(interface)
-    results = parser.finish()
-
-    parser = parser.reset()
-
-    for invalid in invalidUnionTypes:
-        interface = (
-            testPre
-            + string.Template(
-                """
-            interface TestUnion {
-              undefined method(${type} arg);
-            };
-        """
-            ).substitute(type=invalid)
-        )
-
-        threw = False
-        try:
-            parser.parse(interface)
-            results = parser.finish()
-        except:
-            threw = True
-
-        harness.ok(threw, "Should have thrown.")
-
-        parser = parser.reset()
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_union_any.py b/components/script/dom/bindings/codegen/parser/tests/test_union_any.py
deleted file mode 100644
index caba44b55f9..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_union_any.py
+++ /dev/null
@@ -1,16 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface AnyNotInUnion {
-              undefined foo((any or DOMString) arg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_union_nullable.py b/components/script/dom/bindings/codegen/parser/tests/test_union_nullable.py
deleted file mode 100644
index d15ed4cfb54..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_union_nullable.py
+++ /dev/null
@@ -1,60 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface OneNullableInUnion {
-              undefined foo((object? or DOMString?) arg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Two nullable member types of a union should have thrown.")
-
-    parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface NullableInNullableUnion {
-              undefined foo((object? or DOMString)? arg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "A nullable union type with a nullable member type should have " "thrown.",
-    )
-
-    parser.reset()
-    threw = False
-
-    try:
-        parser.parse(
-            """
-            interface NullableInUnionNullableUnionHelper {
-            };
-            interface NullableInUnionNullableUnion {
-              undefined foo(((object? or DOMString) or NullableInUnionNullableUnionHelper)? arg);
-            };
-        """
-        )
-
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "A nullable union type with a nullable member type should have " "thrown.",
-    )
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_usvstring.py b/components/script/dom/bindings/codegen/parser/tests/test_usvstring.py
deleted file mode 100644
index effede391cb..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_usvstring.py
+++ /dev/null
@@ -1,40 +0,0 @@
-# -*- coding: UTF-8 -*-
-
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        interface TestUSVString {
-          attribute USVString svs;
-        };
-    """
-    )
-
-    results = parser.finish()
-
-    harness.check(len(results), 1, "Should be one production")
-    harness.ok(isinstance(results[0], WebIDL.IDLInterface), "Should be an IDLInterface")
-    iface = results[0]
-    harness.check(
-        iface.identifier.QName(), "::TestUSVString", "Interface has the right QName"
-    )
-    harness.check(
-        iface.identifier.name, "TestUSVString", "Interface has the right name"
-    )
-    harness.check(iface.parent, None, "Interface has no parent")
-
-    members = iface.members
-    harness.check(len(members), 1, "Should be one member")
-
-    attr = members[0]
-    harness.ok(isinstance(attr, WebIDL.IDLAttribute), "Should be an IDLAttribute")
-    harness.check(
-        attr.identifier.QName(), "::TestUSVString::svs", "Attr has correct QName"
-    )
-    harness.check(attr.identifier.name, "svs", "Attr has correct name")
-    harness.check(str(attr.type), "USVString", "Attr type is the correct name")
-    harness.ok(attr.type.isUSVString(), "Should be USVString type")
-    harness.ok(attr.type.isString(), "Should be String collective type")
-    harness.ok(not attr.type.isDOMString(), "Should be not be DOMString type")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_variadic_callback.py b/components/script/dom/bindings/codegen/parser/tests/test_variadic_callback.py
deleted file mode 100644
index 3fd3dccd37a..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_variadic_callback.py
+++ /dev/null
@@ -1,13 +0,0 @@
-import WebIDL
-
-
-def WebIDLTest(parser, harness):
-    parser.parse(
-        """
-        callback TestVariadicCallback = any(any... arguments);
-    """
-    )
-
-    results = parser.finish()
-
-    harness.ok(True, "TestVariadicCallback callback parsed without error.")
diff --git a/components/script/dom/bindings/codegen/parser/tests/test_variadic_constraints.py b/components/script/dom/bindings/codegen/parser/tests/test_variadic_constraints.py
deleted file mode 100644
index 06ce09d8236..00000000000
--- a/components/script/dom/bindings/codegen/parser/tests/test_variadic_constraints.py
+++ /dev/null
@@ -1,74 +0,0 @@
-def WebIDLTest(parser, harness):
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface VariadicConstraints1 {
-              undefined foo(byte... arg1, byte arg2);
-            };
-        """
-        )
-        results = parser.finish()
-
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown on variadic argument followed by required " "argument.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface VariadicConstraints2 {
-              undefined foo(byte... arg1, optional byte arg2);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown on variadic argument followed by optional " "argument.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface VariadicConstraints3 {
-              undefined foo(optional byte... arg1);
-            };
-        """
-        )
-        results = parser.finish()
-
-    except:
-        threw = True
-
-    harness.ok(
-        threw,
-        "Should have thrown on variadic argument explicitly flagged as " "optional.",
-    )
-
-    parser = parser.reset()
-    threw = False
-    try:
-        parser.parse(
-            """
-            interface VariadicConstraints4 {
-              undefined foo(byte... arg1 = 0);
-            };
-        """
-        )
-        results = parser.finish()
-    except:
-        threw = True
-
-    harness.ok(threw, "Should have thrown on variadic argument with default value.")