Auto merge of #6223 - nox:merge-generic-functions, r=Ms2ger

Merge generic funs to share them across all bindings (fixes #2684)



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5 files changed, 185 insertions, 200 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index f9e929c68da..832dd564736 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -1441,7 +1441,7 @@ class MethodDefiner(PropertyDefiner):
                 if m.get("methodInfo", True):
                     identifier = m.get("nativeName", m["name"])
                     jitinfo = "&%s_methodinfo" % identifier
-                    accessor = "Some(genericMethod)"
+                    accessor = "Some(generic_method)"
                 else:
                     jitinfo = "0 as *const JSJitInfo"
                     accessor = 'Some(%s)' % m.get("nativeName", m["name"])
@@ -1481,9 +1481,9 @@ class AttrDefiner(PropertyDefiner):
                 jitinfo = "0 as *const JSJitInfo"
             else:
                 if attr.hasLenientThis():
-                    accessor = "genericLenientGetter"
+                    accessor = "generic_lenient_getter"
                 else:
-                    accessor = "genericGetter"
+                    accessor = "generic_getter"
                 jitinfo = "&%s_getterinfo" % attr.identifier.name
 
             return ("JSNativeWrapper { op: Some(%(native)s), info: %(info)s }"
@@ -1499,9 +1499,9 @@ class AttrDefiner(PropertyDefiner):
                 jitinfo = "0 as *const JSJitInfo"
             else:
                 if attr.hasLenientThis():
-                    accessor = "genericLenientSetter"
+                    accessor = "generic_lenient_setter"
                 else:
-                    accessor = "genericSetter"
+                    accessor = "generic_setter"
                 jitinfo = "&%s_setterinfo" % attr.identifier.name
 
             return ("JSNativeWrapper { op: Some(%(native)s), info: %(info)s }"
@@ -2696,52 +2696,6 @@ class CGSetterCall(CGPerSignatureCall):
         # We just get our stuff from our last arg no matter what
         return ""
 
-class CGAbstractBindingMethod(CGAbstractExternMethod):
-    """
-    Common class to generate the JSNatives for all our methods, getters, and
-    setters.  This will generate the function declaration and unwrap the
-    |this| object.  Subclasses are expected to override the generate_code
-    function to do the rest of the work.  This function should return a
-    CGThing which is already properly indented.
-    """
-    def __init__(self, descriptor, name, args, unwrapFailureCode=None):
-        CGAbstractExternMethod.__init__(self, descriptor, name, "u8", args)
-
-        if unwrapFailureCode is None:
-            self.unwrapFailureCode = (
-                'throw_type_error(cx, "\\"this\\" object does not '
-                'implement interface %s.");\n'
-                'return 0;' % descriptor.interface.identifier.name)
-        else:
-            self.unwrapFailureCode = unwrapFailureCode
-
-    def definition_body(self):
-        # Our descriptor might claim that we're not castable, simply because
-        # we're someone's consequential interface.  But for this-unwrapping, we
-        # know that we're the real deal.  So fake a descriptor here for
-        # consumption by FailureFatalCastableObjectUnwrapper.
-        unwrapThis = str(CastableObjectUnwrapper(
-                        FakeCastableDescriptor(self.descriptor),
-                        "obj.handle()", self.unwrapFailureCode, "object"))
-        unwrapThis = CGGeneric(
-            "let args = CallArgs::from_vp(vp, argc);\n"
-            "let thisobj = args.thisv();\n"
-            "if !thisobj.get().is_null_or_undefined() && !thisobj.get().is_object() {\n"
-            "    return JSFalse;\n"
-            "}\n"
-            "let obj = if thisobj.get().is_object() {\n"
-            "    RootedObject::new(cx, thisobj.get().to_object())\n"
-            "} else {\n"
-            "    RootedObject::new(cx, GetGlobalForObjectCrossCompartment(JS_CALLEE(cx, vp).to_object_or_null()))\n"
-            "};\n"
-            "\n"
-            "let this: Root<%s> = %s;\n" % (self.descriptor.concreteType, unwrapThis))
-        return CGList([ unwrapThis, self.generate_code() ], "\n")
-
-    def generate_code(self):
-        assert(False) # Override me
-
-
 class CGAbstractStaticBindingMethod(CGAbstractMethod):
     """
     Common class to generate the JSNatives for all our static methods, getters
@@ -2767,21 +2721,6 @@ let global = global_object_for_js_object(JS_CALLEE(cx, vp).to_object());
     def generate_code(self):
         assert False  # Override me
 
-
-class CGGenericMethod(CGAbstractBindingMethod):
-    """
-    A class for generating the C++ code for an IDL method..
-    """
-    def __init__(self, descriptor):
-        args = [Argument('*mut JSContext', 'cx'), Argument('libc::c_uint', 'argc'),
-                Argument('*mut JSVal', 'vp')]
-        CGAbstractBindingMethod.__init__(self, descriptor, 'genericMethod', args)
-
-    def generate_code(self):
-        return CGGeneric(
-            "let _info: *const JSJitInfo = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));\n"
-            "return CallJitMethodOp(_info, cx, obj.handle(), this.r() as *const _ as *const libc::c_void as *mut libc::c_void, argc, vp);")
-
 class CGSpecializedMethod(CGAbstractExternMethod):
     """
     A class for generating the C++ code for a specialized method that the JIT
@@ -2825,30 +2764,6 @@ class CGStaticMethod(CGAbstractStaticBindingMethod):
         call = CGMethodCall(["global.r()"], nativeName, True, self.descriptor, self.method)
         return CGList([setupArgs, call])
 
-class CGGenericGetter(CGAbstractBindingMethod):
-    """
-    A class for generating the C++ code for an IDL attribute getter.
-    """
-    def __init__(self, descriptor, lenientThis=False):
-        args = [Argument('*mut JSContext', 'cx'), Argument('libc::c_uint', 'argc'),
-                Argument('*mut JSVal', 'vp')]
-        if lenientThis:
-            name = "genericLenientGetter"
-            unwrapFailureCode = (
-                "assert!(JS_IsExceptionPending(cx) == 0);\n"
-                "*vp = UndefinedValue();\n"
-                "return 1;")
-        else:
-            name = "genericGetter"
-            unwrapFailureCode = None
-        CGAbstractBindingMethod.__init__(self, descriptor, name, args,
-                                         unwrapFailureCode)
-
-    def generate_code(self):
-        return CGGeneric(
-            "let info: *const JSJitInfo = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));\n"
-            "return CallJitGetterOp(info, cx, obj.handle(), this.r() as *const _ as *const libc::c_void as *mut libc::c_void, argc, vp);")
-
 class CGSpecializedGetter(CGAbstractExternMethod):
     """
     A class for generating the code for a specialized attribute getter
@@ -2900,34 +2815,6 @@ class CGStaticGetter(CGAbstractStaticBindingMethod):
                             self.attr)
         return CGList([setupArgs, call])
 
-
-class CGGenericSetter(CGAbstractBindingMethod):
-    """
-    A class for generating the Rust code for an IDL attribute setter.
-    """
-    def __init__(self, descriptor, lenientThis=False):
-        args = [Argument('*mut JSContext', 'cx'), Argument('libc::c_uint', 'argc'),
-                Argument('*mut JSVal', 'vp')]
-        if lenientThis:
-            name = "genericLenientSetter"
-            unwrapFailureCode = (
-                "assert!(JS_IsExceptionPending(cx) == 0);\n"
-                "return 1;")
-        else:
-            name = "genericSetter"
-            unwrapFailureCode = None
-        CGAbstractBindingMethod.__init__(self, descriptor, name, args,
-                                         unwrapFailureCode)
-
-    def generate_code(self):
-        return CGGeneric(
-                "let info: *const JSJitInfo = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));\n"
-                "if CallJitSetterOp(info, cx, obj.handle(), this.r() as *const _ as *const libc::c_void as *mut libc::c_void, argc, vp) == 0 {\n"
-                "    return 0;\n"
-                "}\n"
-                "*vp = UndefinedValue();\n"
-                "return 1;")
-
 class CGSpecializedSetter(CGAbstractExternMethod):
     """
     A class for generating the code for a specialized attribute setter
@@ -4641,8 +4528,6 @@ class CGDescriptor(CGThing):
             # cgThings.append(CGGetConstructorObjectMethod(descriptor))
             pass
 
-        (hasMethod, hasGetter, hasLenientGetter,
-         hasSetter, hasLenientSetter) = False, False, False, False, False
         for m in descriptor.interface.members:
             if (m.isMethod() and
                 (not m.isIdentifierLess() or m == descriptor.operations["Stringifier"])):
@@ -4652,7 +4537,6 @@ class CGDescriptor(CGThing):
                 elif not descriptor.interface.isCallback():
                     cgThings.append(CGSpecializedMethod(descriptor, m))
                     cgThings.append(CGMemberJITInfo(descriptor, m))
-                    hasMethod = True
             elif m.isAttr():
                 if m.stringifier:
                     raise TypeError("Stringifier attributes not supported yet. "
@@ -4664,10 +4548,6 @@ class CGDescriptor(CGThing):
                     cgThings.append(CGStaticGetter(descriptor, m))
                 elif not descriptor.interface.isCallback():
                     cgThings.append(CGSpecializedGetter(descriptor, m))
-                    if m.hasLenientThis():
-                        hasLenientGetter = True
-                    else:
-                        hasGetter = True
 
                 if not m.readonly:
                     if m.isStatic():
@@ -4675,27 +4555,12 @@ class CGDescriptor(CGThing):
                         cgThings.append(CGStaticSetter(descriptor, m))
                     elif not descriptor.interface.isCallback():
                         cgThings.append(CGSpecializedSetter(descriptor, m))
-                        if m.hasLenientThis():
-                            hasLenientSetter = True
-                        else:
-                            hasSetter = True
                 elif m.getExtendedAttribute("PutForwards"):
                     cgThings.append(CGSpecializedForwardingSetter(descriptor, m))
-                    hasSetter = True
 
                 if (not m.isStatic() and
                     not descriptor.interface.isCallback()):
                     cgThings.append(CGMemberJITInfo(descriptor, m))
-        if hasMethod:
-            cgThings.append(CGGenericMethod(descriptor))
-        if hasGetter:
-            cgThings.append(CGGenericGetter(descriptor))
-        if hasLenientGetter:
-            cgThings.append(CGGenericGetter(descriptor, lenientThis=True))
-        if hasSetter:
-            cgThings.append(CGGenericSetter(descriptor))
-        if hasLenientSetter:
-            cgThings.append(CGGenericSetter(descriptor, lenientThis=True))
 
         if descriptor.concrete:
             cgThings.append(CGClassFinalizeHook(descriptor))
@@ -5128,6 +4993,9 @@ class CGBindingRoot(CGThing):
             'dom::bindings::utils::{NativeProperties, NativePropertyHooks}',
             'dom::bindings::utils::ConstantVal::{IntVal, UintVal}',
             'dom::bindings::utils::NonNullJSNative',
+            'dom::bindings::utils::{generic_getter, generic_lenient_getter}',
+            'dom::bindings::utils::{generic_lenient_setter, generic_method}',
+            'dom::bindings::utils::generic_setter',
             'dom::bindings::trace::{JSTraceable, RootedTraceable}',
             'dom::bindings::callback::{CallbackContainer,CallbackInterface,CallbackFunction}',
             'dom::bindings::callback::{CallSetup,ExceptionHandling}',
@@ -5756,6 +5624,15 @@ class GlobalGenRoots():
             CGGeneric(AUTOGENERATED_WARNING_COMMENT),
             CGGeneric("pub const MAX_PROTO_CHAIN_LENGTH: usize = %d;\n\n" % config.maxProtoChainLength),
             CGNonNamespacedEnum('ID', protos, [0], deriving="PartialEq, Copy, Clone", repr="u16"),
+            CGWrapper(CGIndenter(CGList([CGGeneric('"' + name + '"') for name in protos],
+                                        ",\n"),
+                                 indentLevel=4),
+                      pre="static INTERFACES: [&'static str; %d] = [\n" % len(protos),
+                      post="\n];\n\n"),
+            CGGeneric("pub fn proto_id_to_name(proto_id: u16) -> &'static str {\n"
+                      "    debug_assert!(proto_id < ID::Count as u16);\n"
+                      "    INTERFACES[proto_id as usize]\n"
+                      "}\n\n"),
             CGNonNamespacedEnum('Proxies', proxies, [0], deriving="PartialEq, Copy, Clone"),
         ])
 
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index 317744907c7..1f29eeb687d 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -41,17 +41,16 @@ use dom::bindings::utils::{Reflectable, Reflector, DOMClass};
 use util::str::DOMString;
 
 use js;
-use js::glue::{RUST_JSID_TO_STRING, RUST_JSID_IS_STRING};
-use js::glue::RUST_JS_NumberValue;
+use js::glue::{GetProxyPrivate, IsWrapper, RUST_JS_NumberValue};
+use js::glue::{RUST_JSID_IS_STRING, RUST_JSID_TO_STRING, UnwrapObject};
 use js::rust::{ToUint64, ToInt64};
 use js::rust::{ToUint32, ToInt32};
 use js::rust::{ToUint16, ToNumber, ToBoolean, ToString};
-use js::jsapi::{JSContext, JSObject, JSString};
-use js::jsapi::{JS_StringHasLatin1Chars, JS_GetLatin1StringCharsAndLength, JS_GetTwoByteStringCharsAndLength};
-use js::jsapi::{JS_NewUCStringCopyN, JS_NewStringCopyN};
-use js::jsapi::{JS_WrapValue};
-use js::jsapi::{JSClass, JS_GetClass};
-use js::jsapi::{HandleId, HandleValue, HandleObject, MutableHandleValue};
+use js::jsapi::{HandleId, HandleObject, HandleValue, JS_GetClass};
+use js::jsapi::{JS_GetLatin1StringCharsAndLength, JS_GetReservedSlot};
+use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_NewStringCopyN};
+use js::jsapi::{JS_NewUCStringCopyN, JS_StringHasLatin1Chars, JS_WrapValue};
+use js::jsapi::{JSClass, JSContext, JSObject, JSString, MutableHandleValue};
 use js::jsval::JSVal;
 use js::jsval::{UndefinedValue, NullValue, BooleanValue, Int32Value, UInt32Value};
 use js::jsval::{StringValue, ObjectValue, ObjectOrNullValue};
@@ -504,25 +503,27 @@ pub fn is_dom_proxy(obj: *mut JSObject) -> bool {
 // globals and non-globals.
 pub const DOM_OBJECT_SLOT: u32 = 0;
 
-/// Get the DOM object from the given reflector.
-pub unsafe fn native_from_reflector<T>(obj: *mut JSObject) -> *const T {
-    use js::jsapi::JS_GetReservedSlot;
-    use js::glue::GetProxyPrivate;
-
+/// Get the private pointer of a DOM object from a given reflector.
+unsafe fn private_from_reflector(obj: *mut JSObject) -> *const libc::c_void {
     let clasp = JS_GetClass(obj);
     let value = if is_dom_class(clasp) {
         JS_GetReservedSlot(obj, DOM_OBJECT_SLOT)
     } else {
-        assert!(is_dom_proxy(obj));
+        debug_assert!(is_dom_proxy(obj));
         GetProxyPrivate(obj)
     };
     if value.is_undefined() {
         ptr::null()
     } else {
-        value.to_private() as *const T
+        value.to_private()
     }
 }
 
+/// Get the DOM object from the given reflector.
+pub unsafe fn native_from_reflector<T>(obj: *mut JSObject) -> *const T {
+    private_from_reflector(obj) as *const T
+}
+
 /// Get the `DOMClass` from `obj`, or `Err(())` if `obj` is not a DOM object.
 unsafe fn get_dom_class(obj: *mut JSObject) -> Result<DOMClass, ()> {
     use dom::bindings::utils::DOMJSClass;
@@ -543,47 +544,57 @@ unsafe fn get_dom_class(obj: *mut JSObject) -> Result<DOMClass, ()> {
     return Err(());
 }
 
-/// Get an `Unrooted<T>` for the given DOM object, unwrapping any wrapper
-/// around it first, and checking if the object is of the correct type.
+/// Get a `*const libc::c_void` for the given DOM object, unwrapping any
+/// wrapper around it first, and checking if the object is of the correct type.
 ///
 /// Returns Err(()) if `obj` is an opaque security wrapper or if the object is
-/// not a reflector for a DOM object of the given type (as defined by the
+/// not an object for a DOM object of the given type (as defined by the
 /// proto_id and proto_depth).
-pub fn native_from_reflector_jsmanaged<T>(mut obj: *mut JSObject) -> Result<Root<T>, ()>
-    where T: Reflectable + IDLInterface
-{
-    use js::glue::{IsWrapper, UnwrapObject};
-
-    unsafe {
-        let dom_class = try!(get_dom_class(obj).or_else(|_| {
-            if IsWrapper(obj) == 1 {
-                debug!("found wrapper");
-                obj = UnwrapObject(obj, /* stopAtOuter = */ 0);
-                if obj.is_null() {
-                    debug!("unwrapping security wrapper failed");
-                    Err(())
-                } else {
-                    assert!(IsWrapper(obj) == 0);
-                    debug!("unwrapped successfully");
-                    get_dom_class(obj)
-                }
-            } else {
-                debug!("not a dom wrapper");
+pub unsafe fn private_from_proto_chain(mut obj: *mut JSObject,
+                                       proto_id: u16, proto_depth: u16)
+                                       -> Result<*const libc::c_void, ()> {
+    let dom_class = try!(get_dom_class(obj).or_else(|_| {
+        if IsWrapper(obj) == 1 {
+            debug!("found wrapper");
+            obj = UnwrapObject(obj, /* stopAtOuter = */ 0);
+            if obj.is_null() {
+                debug!("unwrapping security wrapper failed");
                 Err(())
+            } else {
+                assert!(IsWrapper(obj) == 0);
+                debug!("unwrapped successfully");
+                get_dom_class(obj)
             }
-        }));
-
-        let proto_id = <T as IDLInterface>::get_prototype_id();
-        let proto_depth = <T as IDLInterface>::get_prototype_depth();
-        if dom_class.interface_chain[proto_depth] == proto_id {
-            debug!("good prototype");
-            let native = native_from_reflector(obj);
-            assert!(!native.is_null());
-            Ok(Root::new(NonZero::new(native)))
         } else {
-            debug!("bad prototype");
+            debug!("not a dom wrapper");
             Err(())
         }
+    }));
+
+    if dom_class.interface_chain[proto_depth as usize] as u16 == proto_id {
+        debug!("good prototype");
+        Ok(private_from_reflector(obj))
+    } else {
+        debug!("bad prototype");
+        Err(())
+    }
+}
+
+/// Get a `Root<T>` for the given DOM object, unwrapping any wrapper
+/// around it first, and checking if the object is of the correct type.
+///
+/// Returns Err(()) if `obj` is an opaque security wrapper or if the object is
+/// not a reflector for a DOM object of the given type (as defined by the
+/// proto_id and proto_depth).
+pub fn native_from_reflector_jsmanaged<T>(obj: *mut JSObject) -> Result<Root<T>, ()>
+    where T: Reflectable + IDLInterface
+{
+    let proto_id = <T as IDLInterface>::get_prototype_id() as u16;
+    let proto_depth = <T as IDLInterface>::get_prototype_depth() as u16;
+    unsafe {
+        private_from_proto_chain(obj, proto_id, proto_depth).map(|obj| {
+            Root::new(NonZero::new(obj as *const T))
+        })
     }
 }
 
diff --git a/components/script/dom/bindings/error.rs b/components/script/dom/bindings/error.rs
index 683e5e19feb..9c0567067db 100644
--- a/components/script/dom/bindings/error.rs
+++ b/components/script/dom/bindings/error.rs
@@ -4,6 +4,7 @@
 
 //! Utilities to throw exceptions from Rust bindings.
 
+use dom::bindings::codegen::PrototypeList::proto_id_to_name;
 use dom::bindings::conversions::ToJSValConvertible;
 use dom::bindings::global::GlobalRef;
 use dom::domexception::{DOMException, DOMErrorName};
@@ -149,6 +150,15 @@ pub fn throw_not_in_union(cx: *mut JSContext, names: &'static str) {
     throw_type_error(cx, &error);
 }
 
+/// Throw an exception to signal that a `JSObject` can not be converted to a
+/// given DOM type.
+pub fn throw_invalid_this(cx: *mut JSContext, proto_id: u16) {
+    debug_assert!(unsafe { JS_IsExceptionPending(cx) } == 0);
+    let error = format!("\"this\" object does not implement interface {}.",
+                        proto_id_to_name(proto_id));
+    throw_type_error(cx, &error);
+}
+
 /// Format string used to throw javascript errors.
 static ERROR_FORMAT_STRING_STRING: [libc::c_char; 4] = [
     '{' as libc::c_char,
diff --git a/components/script/dom/bindings/utils.rs b/components/script/dom/bindings/utils.rs
index 43f920a4f02..c57de127dfc 100644
--- a/components/script/dom/bindings/utils.rs
+++ b/components/script/dom/bindings/utils.rs
@@ -6,8 +6,11 @@
 
 use dom::bindings::codegen::PrototypeList;
 use dom::bindings::codegen::PrototypeList::MAX_PROTO_CHAIN_LENGTH;
-use dom::bindings::conversions::{native_from_handleobject, is_dom_class, jsstring_to_str};
-use dom::bindings::error::{Error, ErrorResult, Fallible, throw_type_error};
+use dom::bindings::conversions::{is_dom_class, jsstring_to_str};
+use dom::bindings::conversions::native_from_handleobject;
+use dom::bindings::conversions::private_from_proto_chain;
+use dom::bindings::error::{Error, ErrorResult, Fallible, throw_invalid_this};
+use dom::bindings::error::throw_type_error;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Root;
 use dom::bindings::trace::trace_object;
@@ -24,8 +27,11 @@ use std::ptr;
 use std::cmp::PartialEq;
 use std::default::Default;
 use std::cell::UnsafeCell;
-use js::glue::UnwrapObject;
-use js::glue::{IsWrapper, RUST_JSID_IS_INT, RUST_JSID_TO_INT};
+use js::glue::{CallJitMethodOp, CallJitGetterOp, CallJitSetterOp, IsWrapper};
+use js::glue::{RUST_FUNCTION_VALUE_TO_JITINFO, RUST_JSID_IS_INT};
+use js::glue::{RUST_JSID_TO_INT, UnwrapObject};
+use js::jsapi::{CallArgs, GetGlobalForObjectCrossCompartment, JSJitInfo};
+use js::jsapi::JS_IsExceptionPending;
 use js::jsapi::{JS_AlreadyHasOwnProperty, JS_NewFunction, JSTraceOp};
 use js::jsapi::{JS_DefineProperties, JS_ForwardGetPropertyTo};
 use js::jsapi::{JS_GetClass, JS_LinkConstructorAndPrototype};
@@ -47,13 +53,12 @@ use js::jsapi::{ObjectOpResult, RootedObject, RootedValue, Heap, MutableHandleOb
 use js::jsapi::PropertyDefinitionBehavior;
 use js::jsapi::JSAutoCompartment;
 use js::jsapi::{DOMCallbacks, JSWrapObjectCallbacks};
-use js::jsval::JSVal;
-use js::jsval::{PrivateValue, NullValue};
-use js::jsval::{Int32Value, UInt32Value, DoubleValue, BooleanValue};
+use js::jsval::{BooleanValue, DoubleValue, Int32Value, JSVal, NullValue};
+use js::jsval::{PrivateValue, UInt32Value, UndefinedValue};
 use js::rust::{GCMethods, ToString};
 use js::glue::{WrapperNew, GetCrossCompartmentWrapper};
-use js::{JSPROP_ENUMERATE, JSPROP_READONLY, JSPROP_PERMANENT};
-use js::JSFUN_CONSTRUCTOR;
+use js::{JS_ARGV, JS_CALLEE, JSFUN_CONSTRUCTOR, JSPROP_ENUMERATE};
+use js::{JSPROP_PERMANENT, JSPROP_READONLY};
 use js;
 use string_cache::{Atom, Namespace};
 
@@ -670,6 +675,91 @@ pub unsafe fn delete_property_by_id(cx: *mut JSContext, object: HandleObject,
     JS_DeletePropertyById1(cx, object, id, bp)
 }
 
+unsafe fn generic_call(cx: *mut JSContext, argc: libc::c_uint, vp: *mut JSVal,
+                       is_lenient: bool,
+                       call: unsafe extern fn(*const JSJitInfo, *mut JSContext,
+                                              HandleObject, *mut libc::c_void, u32,
+                                              *mut JSVal)
+                                              -> u8)
+                       -> u8 {
+    let args = CallArgs::from_vp(vp, argc);
+    let thisobj = args.thisv();
+    if !thisobj.get().is_null_or_undefined() && !thisobj.get().is_object() {
+        return 0;
+    }
+    let obj = if thisobj.get().is_object() {
+        thisobj.get().to_object()
+    } else {
+        GetGlobalForObjectCrossCompartment(JS_CALLEE(cx, vp).to_object_or_null())
+    };
+    let obj = RootedObject::new(cx, obj);
+    let info = RUST_FUNCTION_VALUE_TO_JITINFO(JS_CALLEE(cx, vp));
+    let proto_id = (*info).protoID;
+    let depth = (*info).depth;
+    let this = match private_from_proto_chain(obj.ptr, proto_id, depth) {
+        Ok(val) => val,
+        Err(()) => {
+            if is_lenient {
+                debug_assert!(JS_IsExceptionPending(cx) == 0);
+                *vp = UndefinedValue();
+                return 1;
+            } else {
+                throw_invalid_this(cx, proto_id);
+                return 0;
+            }
+        }
+    };
+    call(info, cx, obj.handle(), this as *mut libc::c_void, argc, vp)
+}
+
+/// Generic method of IDL interface.
+pub unsafe extern fn generic_method(cx: *mut JSContext,
+                                    argc: libc::c_uint, vp: *mut JSVal)
+                                    -> u8 {
+    generic_call(cx, argc, vp, false, CallJitMethodOp)
+}
+
+/// Generic getter of IDL interface.
+pub unsafe extern fn generic_getter(cx: *mut JSContext,
+                                    argc: libc::c_uint, vp: *mut JSVal)
+                                    -> u8 {
+    generic_call(cx, argc, vp, false, CallJitGetterOp)
+}
+
+/// Generic lenient getter of IDL interface.
+pub unsafe extern fn generic_lenient_getter(cx: *mut JSContext,
+                                            argc: libc::c_uint,
+                                            vp: *mut JSVal)
+                                            -> u8 {
+    generic_call(cx, argc, vp, true, CallJitGetterOp)
+}
+
+unsafe extern fn call_setter(info: *const JSJitInfo, cx: *mut JSContext,
+                             handle: HandleObject, this: *mut libc::c_void,
+                             argc: u32, vp: *mut JSVal)
+                             -> u8 {
+    if CallJitSetterOp(info, cx, handle, this, argc, vp) == 0 {
+        return 0;
+    }
+    *vp = UndefinedValue();
+    1
+}
+
+/// Generic setter of IDL interface.
+pub unsafe extern fn generic_setter(cx: *mut JSContext,
+                                    argc: libc::c_uint, vp: *mut JSVal)
+                                    -> u8 {
+    generic_call(cx, argc, vp, false, call_setter)
+}
+
+/// Generic lenient setter of IDL interface.
+pub unsafe extern fn generic_lenient_setter(cx: *mut JSContext,
+                                            argc: libc::c_uint,
+                                            vp: *mut JSVal)
+                                            -> u8 {
+    generic_call(cx, argc, vp, true, call_setter)
+}
+
 /// Validate a qualified name. See https://dom.spec.whatwg.org/#validate for details.
 pub fn validate_qualified_name(qualified_name: &str) -> ErrorResult {
     match xml_name_type(qualified_name) {
diff --git a/tests/wpt/metadata/html/dom/interfaces.html.ini b/tests/wpt/metadata/html/dom/interfaces.html.ini
index b1228b4171f..02a810d184b 100644
--- a/tests/wpt/metadata/html/dom/interfaces.html.ini
+++ b/tests/wpt/metadata/html/dom/interfaces.html.ini
@@ -57,9 +57,6 @@
   [Document interface: attribute commands]
     expected: FAIL
 
-  [Document interface: attribute onreadystatechange]
-    expected: FAIL
-
   [Document interface: attribute fgColor]
     expected: FAIL