Catch uncaught promise rejections from V8 and log to console.

Source/bindings/core/v8/V8Initializer.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 12 matching lines @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "bindings/core/v8/V8Initializer.h"
 
 #include "bindings/core/v8/DOMWrapperWorld.h"
 #include "bindings/core/v8/ScriptCallStackFactory.h"
 #include "bindings/core/v8/ScriptController.h"
 #include "bindings/core/v8/ScriptProfiler.h"
+#include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8DOMException.h"
 #include "bindings/core/v8/V8ErrorEvent.h"
 #include "bindings/core/v8/V8ErrorHandler.h"
 #include "bindings/core/v8/V8GCController.h"
 #include "bindings/core/v8/V8History.h"
 #include "bindings/core/v8/V8Location.h"
 #include "bindings/core/v8/V8PerContextData.h"
 #include "bindings/core/v8/V8Window.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/frame/ConsoleTypes.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
+#include "core/inspector/ConsoleMessage.h"
+#include "core/inspector/ScriptArguments.h"
 #include "core/inspector/ScriptCallStack.h"
 #include "platform/EventDispatchForbiddenScope.h"
 #include "platform/TraceEvent.h"
 #include "public/platform/Platform.h"
 #include "wtf/RefPtr.h"
 #include "wtf/text/WTFString.h"
 #include <v8-debug.h>
 
 namespace blink {
 
@@ skipping 90 matching lines @@
         // Allowing error events in private scripts is safe because error events don't propagate to
         // other isolated worlds (which means that the error events won't fire any event listeners
         // in user's scripts).
         EventDispatchForbiddenScope::AllowUserAgentEvents allowUserAgentEvents;
         enteredWindow->document()->reportException(event.release(), scriptId, callStack, corsStatus);
     } else {
         enteredWindow->document()->reportException(event.release(), scriptId, callStack, corsStatus);
     }
 }
 
+typedef WillBeHeapDeque<ScriptValue> PromiseRejectMessageQueue;
+
+static PromiseRejectMessageQueue& promiseRejectMessageQueue()
+{
+    DEFINE_STATIC_LOCAL(OwnPtrWillBePersistent<PromiseRejectMessageQueue>, queue, (adoptPtrWillBeNoop(new PromiseRejectMessageQueue())));
+    return *queue;
+}
+
+void V8Initializer::reportRejectedPromises()
+{
+    ASSERT(isMainThread());
+
+    PromiseRejectMessageQueue& queue = promiseRejectMessageQueue();
+    while (!queue.isEmpty()) {
+        ScriptValue promise = queue.takeFirst();
+        ScriptState* scriptState = promise.scriptState();
+        if (scriptState->contextIsValid())

[pfeldman, 2014/10/06 19:40:13]

That's a really bad name. Lets swap the semantics in a separate patch.

[Jens Widell, 2014/10/07 05:22:23]

https://codereview.chromium.org/622333002/

[aandrey, 2014/10/07 10:03:37]

Acknowledged.

+            continue;
+        ScriptState::Scope scope(scriptState);
+
+        ASSERT(!promise.isEmpty());
+        v8::Handle<v8::Value> value = promise.v8Value();
+        ASSERT(!value.IsEmpty() && value->IsPromise());
+        if (v8::Handle<v8::Promise>::Cast(value)->HasHandler())
+            continue;
+
+        const String errorMessage = "Unhandled promise rejection";
+        Vector<ScriptValue> args;
+        args.append(ScriptValue(scriptState, v8String(scriptState->isolate(), errorMessage)));
+        args.append(promise);
+        RefPtrWillBeRawPtr<ScriptArguments> arguments = ScriptArguments::create(scriptState, args);
+
+        RefPtrWillBeRawPtr<ConsoleMessage> consoleMessage = ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, errorMessage, "", 0);
+        consoleMessage->setScriptArguments(arguments);
+        scriptState->executionContext()->addConsoleMessage(consoleMessage.release());

[yurys, 2014/10/07 05:32:44]

We should be careful not to call this on ScriptState wrapping debugger context
as the latter doesn't have ExecutionState and that would lead to a crash. Can
you check that promises created and reject during evaluation on debugger pause
are reported correctly and add a test for that case?

[aandrey, 2014/10/07 10:03:37]

Added a test, this case does not repro.
Seems like EndOfTaskRunner won't execute while we running debugger message loop.

Anyway, added the NULL check, since scriptState->executionContext()
theoretically can return 0.

+    }
+}
+
+static void promiseRejectHandlerInMainThread(v8::Handle<v8::Promise> promise, v8::Handle<v8::Value> /*value*/, v8::PromiseRejectEvent event)
+{
+    ASSERT(isMainThread());
+
+    if (event != v8::kPromiseRejectWithNoHandler)
+        return;
+
+    // It's possible that promiseRejectHandlerInMainThread() is invoked while we're initializing a window.
+    // In that half-baked situation, we don't have a valid context nor a valid world,
+    // so just return immediately.
+    if (DOMWrapperWorld::windowIsBeingInitialized())
+        return;
+
+    ScriptState* scriptState = ScriptState::current(promise->GetIsolate());
+    promiseRejectMessageQueue().append(ScriptValue(scriptState, promise));
+}
+
 static void failedAccessCheckCallbackInMainThread(v8::Local<v8::Object> host, v8::AccessType type, v8::Local<v8::Value> data)
 {
     v8::Isolate* isolate = v8::Isolate::GetCurrent();
     LocalFrame* target = findFrame(host, data, isolate);
     if (!target)
         return;
     LocalDOMWindow* targetWindow = target->domWindow();
 
     // FIXME: We should modify V8 to pass in more contextual information (context, property, and object).
     ExceptionState exceptionState(ExceptionState::UnknownContext, 0, 0, isolate->GetCurrentContext()->Global(), isolate);
@@ skipping 43 matching lines @@
     v8::Isolate* isolate = V8PerIsolateData::initialize();
 
     initializeV8Common(isolate);
 
     v8::V8::SetFatalErrorHandler(reportFatalErrorInMainThread);
     v8::V8::AddMessageListener(messageHandlerInMainThread);
     v8::V8::SetFailedAccessCheckCallbackFunction(failedAccessCheckCallbackInMainThread);
     v8::V8::SetAllowCodeGenerationFromStringsCallback(codeGenerationCheckCallbackInMainThread);
 
     isolate->SetEventLogger(timerTraceProfilerInMainThread);
+    isolate->SetPromiseRejectCallback(promiseRejectHandlerInMainThread);
 
     ScriptProfiler::initialize();
 }
 
 static void reportFatalErrorInWorker(const char* location, const char* message)
 {
     // FIXME: We temporarily deal with V8 internal error situations such as out-of-memory by crashing the worker.
     CRASH();
 }
 
@@ skipping 35 matching lines @@
     initializeV8Common(isolate);
 
     v8::V8::AddMessageListener(messageHandlerInWorker);
     v8::V8::SetFatalErrorHandler(reportFatalErrorInWorker);
 
     uint32_t here;
     isolate->SetStackLimit(reinterpret_cast<uintptr_t>(&here - kWorkerMaxStackSize / sizeof(uint32_t*)));
 }
 
 } // namespace blink