Implement onunhandledrejection / onrejectionhandled events

Source/bindings/core/v8/RejectedPromises.cpp

 // Copyright 2015 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 "config.h"
 #include "bindings/core/v8/RejectedPromises.h"
 
 #include "bindings/core/v8/ScopedPersistent.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "core/dom/ExecutionContext.h"
+#include "core/events/EventTarget.h"
+#include "core/events/PromiseRejectionEvent.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/inspector/ScriptArguments.h"
+#include "platform/RuntimeEnabledFeatures.h"
 
 namespace blink {
 
 static const unsigned maxReportedHandlersPendingResolution = 1000;
 
 class RejectedPromises::Message final : public NoBaseWillBeGarbageCollectedFinalized<RejectedPromises::Message> {
 public:
     static PassOwnPtrWillBeRawPtr<Message> create(ScriptState* scriptState, v8::Local<v8::Promise> promise, const ScriptValue& exception, const String& errorMessage, const String& resourceName, int scriptId, int lineNumber, int columnNumber, PassRefPtrWillBeRawPtr<ScriptCallStack> callStack)
     {
         return adoptPtrWillBeNoop(new Message(scriptState, promise, exception, errorMessage, resourceName, scriptId, lineNumber, columnNumber, callStack));
@@ skipping 26 matching lines @@
         if (!executionContext)
             return;
 
         ScriptState::Scope scope(m_scriptState);
         v8::Local<v8::Value> value = m_promise.newLocal(m_scriptState->isolate());
         // Either collected or https://crbug.com/450330
         if (value.IsEmpty() || !value->IsPromise())
             return;
         ASSERT(!v8::Local<v8::Promise>::Cast(value)->HasHandler());
 
-        const String errorMessage = "Uncaught (in promise)";
-        Vector<ScriptValue> args;
-        args.append(ScriptValue(m_scriptState, v8String(m_scriptState->isolate(), errorMessage)));
-        args.append(m_exception);
-        RefPtrWillBeRawPtr<ScriptArguments> arguments = ScriptArguments::create(m_scriptState, args);
+        EventTarget* target = executionContext->errorEventTarget();
+        if (RuntimeEnabledFeatures::promiseRejectionEventEnabled() && target) {
+            RefPtrWillBeRawPtr<PromiseRejectionEvent> event = PromiseRejectionEvent::create(EventTypeNames::unhandledrejection, ScriptPromise(m_scriptState, value), m_exception);
+            m_shouldLogToConsole = target->dispatchEvent(event);

[philipj_slow, 2015/06/16 14:58:03]

Can you document this with "Log to console if event was not preventDefault()'ed"
or something? At least I always have to look up what the return value of
dispatchEvent() means.

[jochen (gone - plz use gerrit), 2015/06/17 07:57:53]

done

+        }
 
-        String embedderErrorMessage = m_errorMessage;
-        if (embedderErrorMessage.isEmpty())
-            embedderErrorMessage = errorMessage;
-        else if (embedderErrorMessage.startsWith("Uncaught "))
-            embedderErrorMessage.insert(" (in promise)", 8);
+        if (m_shouldLogToConsole) {
+            const String errorMessage = "Uncaught (in promise)";
+            Vector<ScriptValue> args;
+            args.append(ScriptValue(m_scriptState, v8String(m_scriptState->isolate(), errorMessage)));
+            args.append(m_exception);
+            RefPtrWillBeRawPtr<ScriptArguments> arguments = ScriptArguments::create(m_scriptState, args);
 
-        RefPtrWillBeRawPtr<ConsoleMessage> consoleMessage = ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, embedderErrorMessage, m_resourceName, m_lineNumber, m_columnNumber);
-        consoleMessage->setScriptArguments(arguments);
-        consoleMessage->setCallStack(m_callStack);
-        consoleMessage->setScriptId(m_scriptId);
-        m_consoleMessageId = consoleMessage->assignMessageId();
-        executionContext->addConsoleMessage(consoleMessage.release());
+            String embedderErrorMessage = m_errorMessage;
+            if (embedderErrorMessage.isEmpty())
+                embedderErrorMessage = errorMessage;
+            else if (embedderErrorMessage.startsWith("Uncaught "))
+                embedderErrorMessage.insert(" (in promise)", 8);
+
+            RefPtrWillBeRawPtr<ConsoleMessage> consoleMessage = ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, embedderErrorMessage, m_resourceName, m_lineNumber, m_columnNumber);
+            consoleMessage->setScriptArguments(arguments);
+            consoleMessage->setCallStack(m_callStack);
+            consoleMessage->setScriptId(m_scriptId);
+            m_consoleMessageId = consoleMessage->assignMessageId();
+            executionContext->addConsoleMessage(consoleMessage.release());
+        }
 
         m_callStack.clear();
-        m_exception.clear();
     }
 
     void revoke()
     {
         ExecutionContext* executionContext = m_scriptState->executionContext();
         if (!executionContext)
             return;
 
-        RefPtrWillBeRawPtr<ConsoleMessage> consoleMessage = ConsoleMessage::create(JSMessageSource, RevokedErrorMessageLevel, "Handler added to rejected promise");
-        consoleMessage->setRelatedMessageId(m_consoleMessageId);
-        executionContext->addConsoleMessage(consoleMessage.release());
+        ScriptState::Scope scope(m_scriptState);
+        v8::Local<v8::Value> value = m_promise.newLocal(m_scriptState->isolate());
+        // Either collected or https://crbug.com/450330

[philipj_slow, 2015/06/16 14:58:03]

This issue is 403 for me, what does this comment mean?

[jochen (gone - plz use gerrit), 2015/06/17 07:57:53]

I copied it from ::report()

cc'd you on the bug, I haven't looked into what is happening here

[philipj_slow, 2015/06/17 08:31:00]

Thanks.

+        if (value.IsEmpty() || !value->IsPromise())
+            return;
+
+        EventTarget* target = executionContext->errorEventTarget();
+        if (RuntimeEnabledFeatures::promiseRejectionEventEnabled() && target) {
+            RefPtrWillBeRawPtr<PromiseRejectionEvent> event = PromiseRejectionEvent::create(EventTypeNames::rejectionhandled, ScriptPromise(m_scriptState, value), m_exception);
+            m_shouldLogToConsole &= target->dispatchEvent(event);
+        }
+
+        if (m_shouldLogToConsole) {
+            RefPtrWillBeRawPtr<ConsoleMessage> consoleMessage = ConsoleMessage::create(JSMessageSource, RevokedErrorMessageLevel, "Handler added to rejected promise");
+            consoleMessage->setRelatedMessageId(m_consoleMessageId);
+            executionContext->addConsoleMessage(consoleMessage.release());
+        }
     }
 
 private:
     Message(ScriptState* scriptState, v8::Local<v8::Promise> promise, const ScriptValue& exception, const String& errorMessage, const String& resourceName, int scriptId, int lineNumber, int columnNumber, PassRefPtrWillBeRawPtr<ScriptCallStack> callStack)
         : m_scriptState(scriptState)
         , m_promise(scriptState->isolate(), promise)
         , m_exception(exception)
         , m_errorMessage(errorMessage)
         , m_resourceName(resourceName)
         , m_scriptId(scriptId)
         , m_lineNumber(lineNumber)
         , m_columnNumber(columnNumber)
         , m_callStack(callStack)
         , m_consoleMessageId(0)
         , m_collected(false)
+        , m_shouldLogToConsole(true)
     {
         m_promise.setWeak(this, &Message::didCollectPromise);
     }
 
     static void didCollectPromise(const v8::WeakCallbackInfo<Message>& data)
     {
         data.GetParameter()->m_collected = true;
         data.GetParameter()->m_promise.clear();
     }
 
     ScriptState* m_scriptState;
     ScopedPersistent<v8::Promise> m_promise;
     ScriptValue m_exception;
     String m_errorMessage;
     String m_resourceName;
     int m_scriptId;
     int m_lineNumber;
     int m_columnNumber;
     RefPtrWillBeMember<ScriptCallStack> m_callStack;
     unsigned m_consoleMessageId;
     bool m_collected;
+    bool m_shouldLogToConsole;
 };
 
 RejectedPromises::RejectedPromises()
 {
 }
 
 DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(RejectedPromises);
 
 DEFINE_TRACE(RejectedPromises)
 {
@@ skipping 48 matching lines @@
             continue;
 
         message->report();
         m_reportedAsErrors.append(message.release());
         if (m_reportedAsErrors.size() > maxReportedHandlersPendingResolution)
             m_reportedAsErrors.remove(0, maxReportedHandlersPendingResolution / 10);
     }
 }
 
 } // namespace blink