Implement custom element construction and some 'define' checks

third_party/WebKit/Source/bindings/core/v8/custom/V8HTMLElementCustom.cpp

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "bindings/core/v8/V8HTMLElement.h"
+
+#include "bindings/core/v8/DOMWrapperWorld.h"
+#include "bindings/core/v8/ExceptionState.h"
+#include "bindings/core/v8/V8Binding.h"
+#include "bindings/core/v8/V8BindingMacros.h"
+#include "bindings/core/v8/V8DOMWrapper.h"
+#include "bindings/core/v8/V8ThrowException.h"
+#include "core/dom/Document.h"
+#include "core/dom/custom/CustomElementDefinition.h"
+#include "core/dom/custom/CustomElementsRegistry.h"
+#include "core/frame/LocalDOMWindow.h"
+#include "platform/RuntimeEnabledFeatures.h"
+
+namespace blink {
+
+void V8HTMLElement::constructorCustom(
+    const v8::FunctionCallbackInfo<v8::Value>& info)
+{
+    DCHECK(info.IsConstructCall());
+
+    v8::Isolate* isolate = info.GetIsolate();
+    ScriptState* scriptState = ScriptState::current(isolate);
+
+    if (!RuntimeEnabledFeatures::customElementsV1Enabled()
+        || !scriptState->world().isMainWorld()) {
+        V8ThrowException::throwTypeError(info.GetIsolate(), "Illegal constructor");
+        return;
+    }
+
+    LocalDOMWindow* window = scriptState->domWindow();
+    CustomElementDefinition* def =
+        window->customElements(scriptState)->definitionForConstructor(
+            scriptState,
+            info.NewTarget());
+    if (!def) {
+        V8ThrowException::throwTypeError(isolate, "Illegal constructor");
+        return;
+    }
+
+    // TODO(dominicc): Implement cases where the definition's
+    // construction stack is not empty when parser-creation is
+    // implemented.
+
+    ExceptionState exceptionState(
+        ExceptionState::ConstructionContext,
+        "HTMLElement",
+        info.Holder(),
+        isolate);
+    Element* element = window->document()->createElement(
+        def->localName(),
+        AtomicString(),
+        exceptionState);
+    if (exceptionState.throwIfNeeded())
+        return;
+    const WrapperTypeInfo* wrapperType = element->wrapperTypeInfo();
+    v8::Local<v8::Object> wrapper = V8DOMWrapper::associateObjectWithWrapper(
+        isolate,
+        element,
+        wrapperType,
+        info.This());
+
+    if (!v8CallBoolean(wrapper->SetPrototype(
+        scriptState->context(),
+        def->prototype(scriptState)))) {
+        return;

[yosin_UTC9, 2016/05/12 07:54:22]

Do you forget |V8ThrowException| here?

[dominicc (has gone to gerrit), 2016/05/12 08:00:40]

I'm not sure when that would fail, actually, because we're using a new wrapper
here. I just put the return in there because there will be steps which come
after this.

[bashi, 2016/05/12 08:19:13]

I'm not sure if this would fail but there will be an exception when
v8CallBoolean() returns false because that's the convention of v8 APIs which
returns Maybe<>. I don't think that you need to throw a new exception here.

+    }
+}
+
+} // namespace blink