Add callbacks to ScriptCustomElementDefinition

third_party/WebKit/Source/bindings/core/v8/ScriptCustomElementDefinitionBuilder.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/ScriptCustomElementDefinitionBuilder.h"
 
 #include "bindings/core/v8/DOMWrapperWorld.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptCustomElementDefinition.h"
 #include "bindings/core/v8/ScriptState.h"
@@ skipping 42 matching lines @@
 
         // Constructor is already registered.
         m_exceptionState.throwDOMException(
             NotSupportedError,
             "this constructor has already been used with this registry");
         return false;
     }
     return true;
 }
 
+bool ScriptCustomElementDefinitionBuilder::getValue(
+    const v8::Local<v8::Object>& object, const char* name,
+    v8::Local<v8::Value>& value) const
+{
+    v8::Isolate* isolate = m_scriptState->isolate();
+    v8::Local<v8::Context> context = m_scriptState->context();
+    v8::Local<v8::String> nameString = v8AtomicString(isolate, name);
+    return v8Call(object->Get(context, nameString), value);
+}
+
 bool ScriptCustomElementDefinitionBuilder::checkPrototype()
 {
-    v8::Isolate* isolate = m_scriptState->isolate();
-    v8::Local<v8::Context> context = m_scriptState->context();
-    v8::Local<v8::String> prototypeString =
-        v8AtomicString(isolate, "prototype");
     v8::Local<v8::Value> prototypeValue;
-    if (!v8Call(
-        m_constructor->Get(context, prototypeString), prototypeValue)) {
+    if (!getValue(m_constructor, "prototype", prototypeValue))
         return false;
-    }
     if (!prototypeValue->IsObject()) {
         m_exceptionState.throwTypeError(
             "constructor prototype is not an object");
         return false;
     }
     m_prototype = prototypeValue.As<v8::Object>();
     // If retrieving the prototype destroyed the context, indicate that
     // defining the element should not proceed.
     return true;
 }
 
+bool ScriptCustomElementDefinitionBuilder::getCallable(const char* name,

[yosin_UTC9, 2016/06/02 01:33:38]

It is better to return Optional, or v8::Maybe<v8::Object>, rather than output
variable with bool.
https://chromium.googlesource.com/chromium/src/+/master/third_party/WebKit/So...

Optional may be preferred way since it will be std::optional<T>.

+    v8::Local<v8::Object>& callback) const
+{
+    v8::Local<v8::Value> value;
+    if (!getValue(m_prototype, name, value))
+        return false;
+    if (value->IsUndefined())
+        return true;
+    if (!value->IsObject()) {
+        m_exceptionState.throwTypeError(
+            String::format("\"%s\" is not an object", name));
+        return false;
+    }
+    callback = value.As<v8::Object>();
+    if (!callback->IsCallable()) {
+        m_exceptionState.throwTypeError(
+            String::format("\"%s\" is not callable", name));
+        return false;
+    }
+    return true;
+}
+
+bool ScriptCustomElementDefinitionBuilder::cacheProperties()
+{
+    const char* observedAttributes = "observedAttributes";
+    v8::Local<v8::Value> observedAttributesValue;
+    if (!getValue(m_constructor, observedAttributes, observedAttributesValue))
+        return false;
+    if (!observedAttributesValue->IsUndefined()) {
+        m_observedAttributes = toImplArray<Vector<AtomicString>>(
+            observedAttributesValue, 0, m_scriptState->isolate(),
+            m_exceptionState);
+        if (m_exceptionState.hadException())
+            return false;
+    }
+
+    const char* connectedCallback = "connectedCallback";
+    const char* disconnectedCallback = "disconnectedCallback";
+    const char* attributeChangedCallback = "attributeChangedCallback";
+    return getCallable(connectedCallback, m_connectedCallback)

[dominicc (has gone to gerrit), 2016/06/02 00:31:27]

Please add unit tests which detach the window in callbacks retrieving each of
these properties; with a parsed upgrade candidate existing when define is
called. See the fork() thing in the tests in custom-elements.

+        && getCallable(disconnectedCallback, m_disconnectedCallback)
+        && getCallable(attributeChangedCallback, m_attributeChangedCallback);
+}
+
 CustomElementDefinition* ScriptCustomElementDefinitionBuilder::build(
     const CustomElementDescriptor& descriptor)
 {
-    return ScriptCustomElementDefinition::create(
-        m_scriptState.get(),
-        m_registry,
-        descriptor,
-        m_constructor,
-        m_prototype);
+    return ScriptCustomElementDefinition::create(descriptor, *this);
 }
 
 } // namespace blink