Auto merge of #8412 - ecoal95:webidl-sequence-return, r=jdm

Add WebIDL sequence return values

And use it for `WebGLRenderingContext::getSupportedExtensions`.
Part of #544

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7 files changed, 64 insertions, 5 deletions

diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index 5ac6c455e39..260ef1e9006 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -1295,7 +1295,12 @@ def getRetvalDeclarationForType(returnType, descriptorProvider):
     if returnType.isObject() or returnType.isSpiderMonkeyInterface():
         return CGGeneric("*mut JSObject")
     if returnType.isSequence():
-        raise TypeError("We don't support sequence return values")
+        inner = returnType.unroll()
+        result = getRetvalDeclarationForType(inner, descriptorProvider)
+        result = CGWrapper(result, pre="Vec<", post=">")
+        if returnType.nullable():
+            result = CGWrapper(result, pre="Option<", post=">")
+        return result
     if returnType.isDictionary():
         nullable = returnType.nullable()
         dictName = returnType.inner.name if nullable else returnType.name
diff --git a/components/script/dom/bindings/conversions.rs b/components/script/dom/bindings/conversions.rs
index 45279e7a966..493ed4c0c27 100644
--- a/components/script/dom/bindings/conversions.rs
+++ b/components/script/dom/bindings/conversions.rs
@@ -46,6 +46,7 @@ use js::jsapi::{HandleId, HandleObject, HandleValue, JS_GetClass};
 use js::jsapi::{JSClass, JSContext, JSObject, JSString, MutableHandleValue};
 use js::jsapi::{JS_GetLatin1StringCharsAndLength, JS_GetReservedSlot};
 use js::jsapi::{JS_GetTwoByteStringCharsAndLength, JS_NewStringCopyN};
+use js::jsapi::{JS_NewArrayObject1, JS_DefineElement, RootedValue, RootedObject};
 use js::jsapi::{JS_NewUCStringCopyN, JS_StringHasLatin1Chars, JS_WrapValue};
 use js::jsval::{BooleanValue, Int32Value, NullValue, UInt32Value, UndefinedValue};
 use js::jsval::{JSVal, ObjectOrNullValue, ObjectValue, StringValue};
@@ -811,6 +812,28 @@ impl<T: FromJSValConvertible> FromJSValConvertible for Option<T> {
     }
 }
 
+impl<T: ToJSValConvertible> ToJSValConvertible for Vec<T> {
+    fn to_jsval(&self, cx: *mut JSContext, rval: MutableHandleValue) {
+        let js_array = RootedObject::new(cx,
+                                         unsafe { JS_NewArrayObject1(cx, self.len() as libc::size_t) });
+        assert!(!js_array.handle().is_null());
+
+        for (index, obj) in self.iter().enumerate() {
+            let mut val = RootedValue::new(cx, UndefinedValue());
+            obj.to_jsval(cx, val.handle_mut());
+
+            unsafe {
+                assert!(JS_DefineElement(cx, js_array.handle(),
+                                         index as u32, val.handle(), js::JSPROP_ENUMERATE, None, None));
+            }
+        }
+
+        unsafe {
+            rval.set(ObjectValue(&*js_array.handle().get()));
+        }
+    }
+}
+
 //http://heycam.github.io/webidl/#es-object
 impl ToJSValConvertible for *mut JSObject {
     fn to_jsval(&self, cx: *mut JSContext, rval: MutableHandleValue) {
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 875f88628f4..4855bcc36de 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -245,6 +245,11 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.14
+    fn GetSupportedExtensions(&self) -> Option<Vec<DOMString>> {
+        Some(vec![])
+    }
+
+    // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.14
     fn GetExtension(&self, _cx: *mut JSContext, _name: DOMString) -> *mut JSObject {
         // TODO(ecoal95) we actually do not support extensions.
         // `getSupportedExtensions` cannot be implemented as of right now (see #544)
diff --git a/components/script/dom/webidls/WebGLRenderingContext.webidl b/components/script/dom/webidls/WebGLRenderingContext.webidl
index 957220efa54..27019ed7754 100644
--- a/components/script/dom/webidls/WebGLRenderingContext.webidl
+++ b/components/script/dom/webidls/WebGLRenderingContext.webidl
@@ -471,7 +471,7 @@ interface WebGLRenderingContextBase
     [WebGLHandlesContextLoss] WebGLContextAttributes? getContextAttributes();
     //[WebGLHandlesContextLoss] boolean isContextLost();
 
-    //sequence<DOMString>? getSupportedExtensions();
+    sequence<DOMString>? getSupportedExtensions();
     object? getExtension(DOMString name);
 
     void activeTexture(GLenum texture);
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 117bdbf5407..30c6d7f71a4 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -5047,10 +5047,16 @@
             "url": "/_mozilla/mozilla/variadic-interface.html"
           }
         ],
-        "mozilla/webgl_context_creation_error.html": [
+        "mozilla/webgl/context_creation_error.html": [
           {
-            "path": "mozilla/webgl_context_creation_error.html",
-            "url": "/_mozilla/mozilla/webgl_context_creation_error.html"
+            "path": "mozilla/webgl/context_creation_error.html",
+            "url": "/_mozilla/mozilla/webgl/context_creation_error.html"
+          }
+        ],
+        "mozilla/webgl/get_supported_extensions.html": [
+          {
+            "path": "mozilla/webgl/get_supported_extensions.html",
+            "url": "/_mozilla/mozilla/webgl/get_supported_extensions.html"
           }
         ],
         "mozilla/websocket_connection_fail.html": [
diff --git a/tests/wpt/mozilla/tests/mozilla/webgl_context_creation_error.html b/tests/wpt/mozilla/tests/mozilla/webgl/context_creation_error.html
index 8b62ba1fd8e..8b62ba1fd8e 100644
--- a/tests/wpt/mozilla/tests/mozilla/webgl_context_creation_error.html
+++ b/tests/wpt/mozilla/tests/mozilla/webgl/context_creation_error.html
diff --git a/tests/wpt/mozilla/tests/mozilla/webgl/get_supported_extensions.html b/tests/wpt/mozilla/tests/mozilla/webgl/get_supported_extensions.html
new file mode 100644
index 00000000000..691535db476
--- /dev/null
+++ b/tests/wpt/mozilla/tests/mozilla/webgl/get_supported_extensions.html
@@ -0,0 +1,20 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>WebGLContextEvent getSupportedExtensions test</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+test(function() {
+  var gl = document.createElement("canvas").getContext("webgl");
+
+  if (!gl)
+    return;
+
+  var extensions = gl.getSupportedExtensions();
+  assert_true(Array.isArray(extensions), "getSupportedExtensions should return an array");
+
+  for (var i = 0; i < extensions.length; ++i)
+    assert_true(typeof(extensions[i]) === "string", "Extensions should be strings, got " + typeof(extensions[i]));
+
+});
+</script>