JS errors thrown in private scripts should be reported to stderr in Debug builds

Source/bindings/core/v8/PrivateScriptRunner.cpp

 // Copyright 2014 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/PrivateScriptRunner.h"
 
 #include "bindings/core/v8/DOMWrapperWorld.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/V8Binding.h"
@@ skipping 187 matching lines @@
     v8::Handle<v8::Object> classObject = classObjectOfPrivateScript(scriptState, className);
     v8::Handle<v8::Value> method = classObject->Get(v8String(scriptState->isolate(), methodName));
     if (method.IsEmpty() || !method->IsFunction()) {
         LOG_ERROR_ALWAYS("Private script error: Target DOM method was not found. (Class name = %s, Method name = %s)\n", className.utf8().data(), methodName.utf8().data());
         RELEASE_ASSERT_NOT_REACHED();
     }
     initializeHolderIfNeeded(scriptState, classObject, holder);
     return V8ScriptRunner::callFunction(v8::Handle<v8::Function>::Cast(method), scriptState->executionContext(), holder, argc, argv, scriptState->isolate());
 }
 
-bool PrivateScriptRunner::throwDOMExceptionInPrivateScriptIfNeeded(v8::Isolate* isolate, ExceptionState& exceptionState, v8::Handle<v8::Value> exception)
+static void dumpJSError(String exceptionName, String message)
 {
+    // FIXME: Set a ScriptOrigin of the private script and print a more informative message.
+#ifndef NDEBUG
+    fprintf(stderr, "Private script throws an exception: %s\n", exceptionName.utf8().data());

[haraken, 2014/08/12 02:38:33]

I used fprintf(stderr) instead of WTF_LOG_ERROR, because WTF_LOG_ERROR prints
__FILE__ and __LINE__ of this code, like this:


ERROR: Private script throws an exception: ReferenceError

../../third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp(212) :
void blink::dumpJSError(WTF::String, WTF::String)
ERROR: bbb is not defined

../../third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp(214) :
void blink::dumpJSError(WTF::String, WTF::String)

+    if (!message.isEmpty())
+        fprintf(stderr, "%s\n", message.utf8().data());
+#endif
+}
+
+bool PrivateScriptRunner::rethrowExceptionInPrivateScript(v8::Isolate* isolate, ExceptionState& exceptionState, v8::TryCatch& block)
+{
+    v8::Handle<v8::Value> exception = block.Exception();
     if (exception.IsEmpty() || !exception->IsObject())
         return false;
 
     v8::Handle<v8::Object> exceptionObject = v8::Handle<v8::Object>::Cast(exception);
     v8::Handle<v8::Value> name = exceptionObject->Get(v8String(isolate, "name"));
     if (name.IsEmpty() || !name->IsString())
         return false;
     String exceptionName = toCoreString(v8::Handle<v8::String>::Cast(name));
     if (exceptionName == "DOMExceptionInPrivateScript") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
         v8::Handle<v8::Value> code = exceptionObject->Get(v8String(isolate, "code"));
         RELEASE_ASSERT(!code.IsEmpty() && code->IsInt32());
-        exceptionState.throwDOMException(toInt32(code), toCoreString(v8::Handle<v8::String>::Cast(message)));
+        exceptionState.throwDOMException(toInt32(code), toCoreString(v8::Handle<v8::String>::Cast(v8Message)));
         exceptionState.throwIfNeeded();
         return true;
     }
     if (exceptionName == "Error") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
-        exceptionState.throwDOMException(V8GeneralError, toCoreString(v8::Handle<v8::String>::Cast(message)));
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
+        String message = toCoreString(v8::Handle<v8::String>::Cast(v8Message));
+        exceptionState.throwDOMException(V8GeneralError, message);
         exceptionState.throwIfNeeded();
+        dumpJSError(exceptionName, message);
         return true;
     }
     if (exceptionName == "TypeError") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
-        exceptionState.throwDOMException(V8TypeError, toCoreString(v8::Handle<v8::String>::Cast(message)));
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
+        String message = toCoreString(v8::Handle<v8::String>::Cast(v8Message));
+        exceptionState.throwDOMException(V8TypeError, message);
         exceptionState.throwIfNeeded();
+        dumpJSError(exceptionName, message);
         return true;
     }
     if (exceptionName == "RangeError") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
-        exceptionState.throwDOMException(V8RangeError, toCoreString(v8::Handle<v8::String>::Cast(message)));
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
+        String message = toCoreString(v8::Handle<v8::String>::Cast(v8Message));
+        exceptionState.throwDOMException(V8RangeError, message);
         exceptionState.throwIfNeeded();
+        dumpJSError(exceptionName, message);
         return true;
     }
     if (exceptionName == "SyntaxError") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
-        exceptionState.throwDOMException(V8SyntaxError, toCoreString(v8::Handle<v8::String>::Cast(message)));
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
+        String message = toCoreString(v8::Handle<v8::String>::Cast(v8Message));
+        exceptionState.throwDOMException(V8SyntaxError, message);
         exceptionState.throwIfNeeded();
+        dumpJSError(exceptionName, message);
         return true;
     }
     if (exceptionName == "ReferenceError") {
-        v8::Handle<v8::Value> message = exceptionObject->Get(v8String(isolate, "message"));
-        RELEASE_ASSERT(!message.IsEmpty() && message->IsString());
-        exceptionState.throwDOMException(V8ReferenceError, toCoreString(v8::Handle<v8::String>::Cast(message)));
+        v8::Handle<v8::Value> v8Message = exceptionObject->Get(v8String(isolate, "message"));
+        RELEASE_ASSERT(!v8Message.IsEmpty() && v8Message->IsString());
+        String message = toCoreString(v8::Handle<v8::String>::Cast(v8Message));
+        exceptionState.throwDOMException(V8ReferenceError, message);
         exceptionState.throwIfNeeded();
+        dumpJSError(exceptionName, message);
         return true;
     }
     return false;
 }
 
 } // namespace blink