Implement script-side of callback reactions for Custom Elements V1

third_party/WebKit/Source/bindings/core/v8/ScriptCustomElementDefinition.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/ScriptCustomElementDefinition.h"
 
+#include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8BindingMacros.h"
 #include "bindings/core/v8/V8CustomElementsRegistry.h"
 #include "bindings/core/v8/V8Element.h"
 #include "bindings/core/v8/V8HiddenValue.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
 #include "bindings/core/v8/V8ThrowException.h"
 #include "core/dom/ExceptionCode.h"
 #include "v8.h"
@@ skipping 56 matching lines @@
     //
     // At a meta-level, this downcast is safe because there is
     // currently only one implementation of CustomElementDefinition in
     // product code and that is ScriptCustomElementDefinition. But
     // that may change in the future.
     CustomElementDefinition* definition = registry->definitionForName(name);
     CHECK(definition);
     return static_cast<ScriptCustomElementDefinition*>(definition);
 }
 
+template <typename T>
 static void keepAlive(v8::Local<v8::Array>& array, uint32_t index,
-    const v8::Local<v8::Object>& value,
-    ScopedPersistent<v8::Object>& persistent,
+    const v8::Local<T>& value,
+    ScopedPersistent<T>& persistent,
     ScriptState* scriptState)
 {
     if (value.IsEmpty())
         return;
 
     v8CallOrCrash(array->Set(scriptState->context(), index, value));
 
     persistent.set(scriptState->isolate(), value);
     persistent.setPhantom();
 }
 
 ScriptCustomElementDefinition* ScriptCustomElementDefinition::create(
     ScriptState* scriptState,
     CustomElementsRegistry* registry,
     const CustomElementDescriptor& descriptor,
     const v8::Local<v8::Object>& constructor,
     const v8::Local<v8::Object>& prototype,
-    const v8::Local<v8::Object>& connectedCallback,
-    const v8::Local<v8::Object>& disconnectedCallback,
-    const v8::Local<v8::Object>& attributeChangedCallback,
+    const v8::Local<v8::Function>& connectedCallback,
+    const v8::Local<v8::Function>& disconnectedCallback,
+    const v8::Local<v8::Function>& attributeChangedCallback,
     const HashSet<AtomicString>& observedAttributes)
 {
     ScriptCustomElementDefinition* definition =
         new ScriptCustomElementDefinition(
             scriptState,
             descriptor,
             constructor,
             prototype,
             connectedCallback,
             disconnectedCallback,
@@ skipping 18 matching lines @@
     v8CallOrCrash(map->Set(scriptState->context(), nameValue, array));
 
     return definition;
 }
 
 ScriptCustomElementDefinition::ScriptCustomElementDefinition(
     ScriptState* scriptState,
     const CustomElementDescriptor& descriptor,
     const v8::Local<v8::Object>& constructor,
     const v8::Local<v8::Object>& prototype,
-    const v8::Local<v8::Object>& connectedCallback,
-    const v8::Local<v8::Object>& disconnectedCallback,
-    const v8::Local<v8::Object>& attributeChangedCallback,
+    const v8::Local<v8::Function>& connectedCallback,
+    const v8::Local<v8::Function>& disconnectedCallback,
+    const v8::Local<v8::Function>& attributeChangedCallback,
     const HashSet<AtomicString>& observedAttributes)
     : CustomElementDefinition(descriptor)
     , m_scriptState(scriptState)
     , m_constructor(scriptState->isolate(), constructor)
-    , m_observedAttributes(observedAttributes)
 {
+    m_observedAttributes = observedAttributes;

[dominicc (has gone to gerrit), 2016/06/14 09:19:45]

We should make the CustomElementDefinition take observed attributes in its
constructor; no need to make the state mutable by the derived class.

 }
 
 // https://html.spec.whatwg.org/multipage/scripting.html#upgrades
 bool ScriptCustomElementDefinition::runConstructor(Element* element)
 {
     if (!m_scriptState->contextIsValid())
         return false;
     ScriptState::Scope scope(m_scriptState.get());
     v8::Isolate* isolate = m_scriptState->isolate();
 
@@ skipping 39 matching lines @@
     DCHECK(!m_prototype.isEmpty());
     return m_prototype.newLocal(m_scriptState->isolate());
 }
 
 // CustomElementDefinition
 ScriptValue ScriptCustomElementDefinition::getConstructorForScript()
 {
     return ScriptValue(m_scriptState.get(), constructor());
 }
 
+bool ScriptCustomElementDefinition::hasConnectedCallback() const
+{
+    return !m_connectedCallback.isEmpty();
+}
+
+bool ScriptCustomElementDefinition::hasDisconnectedCallback() const
+{
+    return !m_disconnectedCallback.isEmpty();
+}
+
+void ScriptCustomElementDefinition::runCallback(
+    ScopedPersistent<v8::Function>& callback,
+    Element* element, int argc, v8::Local<v8::Value> argv[])
+{
+    if (!m_scriptState->contextIsValid())
+        return;
+    ScriptState::Scope scope(m_scriptState.get());
+    v8::Isolate* isolate = m_scriptState->isolate();
+
+    // Invoke custom element reactions
+    // https://html.spec.whatwg.org/multipage/scripting.html#invoke-custom-element-reactions
+    // If this throws any exception, then report the exception.
+    v8::TryCatch tryCatch(isolate);
+    tryCatch.SetVerbose(true);
+
+    ExecutionContext* executionContext = m_scriptState->getExecutionContext();
+    v8::Local<v8::Value> elementHandle = toV8(element,
+        m_scriptState->context()->Global(), isolate);
+    ScriptController::callFunction(
+        executionContext,
+        callback.newLocal(isolate),
+        elementHandle,
+        argc, argv, isolate);
+}
+
+void ScriptCustomElementDefinition::runConnectedCallback(Element* element)
+{
+    runCallback(m_connectedCallback, element);
+}
+
+void ScriptCustomElementDefinition::runDisconnectedCallback(Element* element)
+{
+    runCallback(m_disconnectedCallback, element);
+}
+
+static v8::Local<v8::Value> v8StringOrNull(v8::Isolate* isolate,

[dominicc (has gone to gerrit), 2016/06/14 09:19:45]

This is a nice little helper; maybe this should live in V8Binding.h, I guess?

+    const AtomicString& value)
+{
+    if (value.isNull())
+        return v8::Null(isolate);
+    return v8String(isolate, value);
+}
+
+void ScriptCustomElementDefinition::runAttributeChangedCallback(
+    Element* element, const QualifiedName& name,
+    const AtomicString& oldValue, const AtomicString& newValue)
+{
+    v8::Isolate* isolate = m_scriptState->isolate();

[dominicc (has gone to gerrit), 2016/06/14 09:19:45]

This needs to set up the ScriptState::Scope just like runCallback does.

+    const int argc = 4;
+    v8::Local<v8::Value> argv[argc] = {
+        v8String(isolate, name.localName()),
+        v8StringOrNull(isolate, oldValue),
+        v8StringOrNull(isolate, newValue),
+        v8String(isolate, name.namespaceURI()),
+    };
+    runCallback(m_attributeChangedCallback, element, argc, argv);
+}
+
 } // namespace blink