Merge DevTools Refactor CL to Blink36

Source/bindings/dart/DartScriptDebugServer.cpp

+/*
+ * Copyright (C) 2014 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:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "config.h"
+#include "bindings/dart/DartScriptDebugServer.h"
+
+#include "bindings/dart/DartController.h"
+#include "bindings/dart/DartHandleProxy.h"
+#include "bindings/dart/DartUtilities.h"
+#include "bindings/dart/V8Converter.h"
+#include "bindings/v8/PageScriptDebugServer.h"
+#include "bindings/v8/ScriptController.h"
+#include "bindings/v8/V8Binding.h"
+#include "bindings/v8/V8ScriptState.h"
+#include "bindings/v8/V8WindowShell.h"
+#include "core/dom/Document.h"
+#include "core/frame/DOMWindow.h"
+#include "core/inspector/InspectorController.h"
+#include "core/inspector/InspectorDebuggerAgent.h"
+#include "core/inspector/InspectorInstrumentation.h"
+#include "core/inspector/InstrumentingAgents.h"
+#include "core/inspector/JSONParser.h"
+#include "core/inspector/ScriptDebugListener.h"
+#include "core/page/Page.h"
+#include "platform/JSONValues.h"
+#include "platform/Logging.h"
+#include "wtf/HashMap.h"
+#include "wtf/Vector.h"
+
+namespace WebCore {
+
+static Dart_ExceptionPauseInfo calculatePauseInfo(ScriptDebugServer::PauseOnExceptionsState pauseOnExceptionState)
+{
+    switch (pauseOnExceptionState) {
+    case ScriptDebugServer::DontPauseOnExceptions:
+        return kNoPauseOnExceptions;
+    case ScriptDebugServer::PauseOnAllExceptions:
+        return kPauseOnAllExceptions;
+    case ScriptDebugServer::PauseOnUncaughtExceptions:
+        return kPauseOnUnhandledExceptions;
+    }
+    return kNoPauseOnExceptions;
+}
+
+DartBreakpoint::DartBreakpoint(intptr_t breakpointId, Dart_Isolate isolate)
+    : m_breakpointId(breakpointId)
+    , m_isolate(isolate)
+{
+}
+
+DartBreakpointInfo::DartBreakpointInfo(const String& scriptUrl, const ScriptBreakpoint& scriptBreakpoint)
+    : m_scriptUrl(scriptUrl)
+    , m_scriptBreakpoint(scriptBreakpoint)
+{
+}
+
+DartPageDebug::DartPageDebug(Page* page, size_t pageId)
+    : m_page(page)
+    , m_listener(0)
+    , m_pageId(pageId)
+    , m_nextBreakpointId(1)
+    , m_nextScriptId(1)
+{
+}
+
+DartPageDebug::~DartPageDebug()
+{
+    for (BreakpointMap::iterator it = m_breakpoints.begin(); it != m_breakpoints.end(); ++it)
+        delete it->value;
+}
+
+void DartPageDebug::registerIsolate(Dart_Isolate isolate)
+{
+    m_isolateMap.add(isolate);
+}
+
+intptr_t DartPageDebug::setBreakpointHelper(DartBreakpointInfo* breakpointInfo, const String& breakpointIdString, Dart_Isolate isolate, Dart_Handle& exception)
+{
+    Dart_Handle scriptURL = DartUtilities::convertSourceString(breakpointInfo->m_scriptUrl);
+    // FIXME: use scriptBreakpoint.columnNumber and ScriptBreakpoint.condition as well.
+    Dart_Handle ret = Dart_SetBreakpoint(scriptURL, breakpointInfo->m_scriptBreakpoint.lineNumber + 1);
+    if (Dart_IsError(ret)) {
+        exception = ret;
+        return 0;
+    }
+    ASSERT(Dart_IsInteger(ret));
+    intptr_t breakpointId = DartUtilities::dartToInt(ret, exception);
+    ASSERT(!exception);
+    if (exception) {
+        return 0;
+    }
+    m_breakpointIdMap.set(breakpointId, breakpointIdString);
+    breakpointInfo->m_breakpoints.append(DartBreakpoint(breakpointId, isolate));
+    return breakpointId;
+}
+
+String DartPageDebug::setBreakpoint(const String& sourceID, const ScriptBreakpoint& scriptBreakpoint, int* actualLineNumber, int* actualColumnNumber, bool interstatementLocation)
+{
+    String breakpointIdString = String::format("{\"dartBreakpoint\":%ld,\"page\":%ld}", m_nextBreakpointId, m_pageId);
+
+    m_nextBreakpointId++;
+    if (!m_idToScriptUrlMap.contains(sourceID)) {
+        return "Unable to set breakpoint. Unknown sourceID";
+    }
+    Vector<Dart_Isolate> isolates;
+    m_isolateMap.copyValues(isolates);
+    for (Vector<Dart_Isolate>::iterator it = isolates.begin(); it != isolates.end(); ++it) {
+        Dart_Isolate isolate = *it;
+        DartIsolateScope scope(isolate);
+        DartApiScope apiScope;
+        Dart_Handle exception = 0;
+
+        DartBreakpointInfo* breakpointInfo;
+        BreakpointMap::iterator breakpointIt = m_breakpoints.find(breakpointIdString);
+        if (breakpointIt != m_breakpoints.end()) {
+            breakpointInfo = breakpointIt->value;
+        } else {
+            breakpointInfo = new DartBreakpointInfo(m_idToScriptUrlMap.get(sourceID), scriptBreakpoint);
+            m_breakpoints.set(breakpointIdString, breakpointInfo);
+        }
+
+        intptr_t breakpointId = setBreakpointHelper(breakpointInfo, breakpointIdString, isolate, exception);
+        if (exception) {
+            continue;
+        }
+        Dart_Handle breakpointLine = Dart_GetBreakpointLine(breakpointId);
+        *actualColumnNumber = 0;
+        if (!Dart_IsError(breakpointLine)) {
+            ASSERT(Dart_IsInteger(breakpointLine));
+            *actualLineNumber = DartUtilities::dartToInt(breakpointLine, exception) - 1;
+            ASSERT(!exception);
+        } else {
+            *actualLineNumber = 1;
+        }
+    }
+    return breakpointIdString;
+}
+
+
+void DartPageDebug::removeBreakpointHelper(DartBreakpointInfo* breakpointInfo)
+{
+    Vector<DartBreakpoint>& breakpoints = breakpointInfo->m_breakpoints;
+    for (Vector<DartBreakpoint>::iterator it = breakpoints.begin(); it != breakpoints.end(); ++it) {
+        DartBreakpoint& breakpoint = *it;
+        DartIsolateScope scope(breakpoint.m_isolate);
+        DartApiScope apiScope;
+        // perhaps this isn't needed if the isolate will be removed soon anyway.
+        Dart_RemoveBreakpoint(breakpoint.m_breakpointId);
+    }
+    delete breakpointInfo;
+}
+
+void DartPageDebug::removeBreakpoint(const String& breakpointId)
+{
+    if (m_breakpoints.contains(breakpointId)) {
+        removeBreakpointHelper(m_breakpoints.get(breakpointId));
+        m_breakpoints.remove(breakpointId);
+    }
+}
+
+void DartPageDebug::clearBreakpointsForIsolate(Dart_Isolate isolate)
+{
+    // Warning: this code is O(num_isolates * num_breakpoints)
+    for (BreakpointMap::iterator i = m_breakpoints.begin(); i != m_breakpoints.end(); ++i) {
+        Vector<DartBreakpoint>& breakpoints = i->value->m_breakpoints;
+        for (size_t j = 0; j < breakpoints.size(); j++) {
+            DartBreakpoint& breakpoint = breakpoints[j];
+            if (breakpoint.m_isolate == isolate) {
+                // No need to actually call Dart_RemoveBreakpoint as the
+                // isolate is about to be shut down.
+                breakpoints.remove(j);
+                break;
+            }
+        }
+    }
+}
+
+void DartPageDebug::dispatchDidParseSource(intptr_t libraryId, Dart_Handle scriptURL, Dart_Isolate isolate)
+{
+    ASSERT(Dart_IsString(scriptURL));
+    ScriptDebugListener::Script script;
+    script.url = DartUtilities::toString(scriptURL);
+    String sourceID = getScriptId(script.url);
+    script.source = DartUtilities::toString(Dart_ScriptGetSource(libraryId, scriptURL));
+    // FIXME: track script.sourceMappingURL for dart-dart source map support.
+
+    Dart_Handle info = Dart_ScriptGetTokenInfo(libraryId, scriptURL);
+    ASSERT(Dart_IsList(info));
+    intptr_t infoLength = 0;
+    Dart_Handle ALLOW_UNUSED result = Dart_ListLength(info, &infoLength);
+    ASSERT(!Dart_IsError(result));
+    Dart_Handle elem;
+    int lastLineNumber = 0;
+    int lastColumnNumber = 0;
+    intptr_t lastLineStart = 0;
+    for (intptr_t i = infoLength - 3; i >= 0; i--) {
+        elem = Dart_ListGetAt(info, i);
+        if (Dart_IsNull(elem)) {
+            lastLineStart = i;
+            break;
+        }
+    }
+    Dart_Handle exception = 0;
+    lastLineNumber = DartUtilities::toInteger(Dart_ListGetAt(info, lastLineStart + 1), exception);
+    ASSERT(!exception);
+    lastColumnNumber = DartUtilities::toInteger(Dart_ListGetAt(info, infoLength - 1), exception);
+    ASSERT(!exception);
+
+    script.startLine = 0;
+    script.startColumn = 0;
+    script.endLine = lastLineNumber + 1;
+    script.endColumn = !lastLineNumber ? lastColumnNumber : 0;
+    script.isContentScript = false;
+    script.language = String("dart");
+    script.libraryId = libraryId;
+    m_listener->didParseSource(sourceID, script);
+}
+
+String DartPageDebug::getScriptId(const String& url)
+{
+    HashMap<String, String>::iterator it = m_scriptUrlToIdMap.find(url);
+    if (it == m_scriptUrlToIdMap.end()) {
+        String id = String::format("{\"dartScript\":%ld,\"page\":%ld}", m_nextScriptId, m_pageId);
+        m_nextScriptId++;
+        m_scriptUrlToIdMap.set(url, id);
+        m_idToScriptUrlMap.set(id, url);
+        return id;
+    }
+    return it->value;
+}
+
+void DartPageDebug::clearBreakpoints()
+{
+    for (BreakpointMap::iterator i = m_breakpoints.begin(); i != m_breakpoints.end(); ++i)
+        removeBreakpointHelper(i->value);
+    m_breakpoints.clear();
+    m_breakpointIdMap.clear();
+}
+
+void DartPageDebug::registerIsolateScripts(Dart_Isolate isolate)
+{
+    Dart_Handle libraries = Dart_GetLibraryIds();
+    ASSERT(Dart_IsList(libraries));
+
+    intptr_t librariesLength = 0;
+    Dart_Handle ALLOW_UNUSED result = Dart_ListLength(libraries, &librariesLength);
+    ASSERT(!Dart_IsError(result));
+    for (intptr_t i = 0; i < librariesLength; ++i) {
+        Dart_Handle libraryIdHandle = Dart_ListGetAt(libraries, i);
+        ASSERT(!Dart_IsError(libraryIdHandle));
+        Dart_Handle exception = 0;
+        int64_t int64LibraryId = DartUtilities::toInteger(libraryIdHandle, exception);
+        ASSERT(!exception);
+        intptr_t libraryId = static_cast<intptr_t>(int64LibraryId);
+        ASSERT(libraryId == int64LibraryId);
+
+        Dart_Handle libraryURL = Dart_GetLibraryURL(libraryId);
+        ASSERT(Dart_IsString(libraryURL));
+
+        // FIXMEDART: we may be doing this more than once per library.
+        Dart_SetLibraryDebuggable(libraryId, true);
+
+        Dart_Handle scripts = Dart_GetScriptURLs(libraryURL);
+        ASSERT(Dart_IsList(scripts));
+
+        intptr_t scriptsLength = 0;
+        result = Dart_ListLength(scripts, &scriptsLength);
+        ASSERT(!Dart_IsError(result));
+        for (intptr_t j = 0; j < scriptsLength; ++j) {
+            Dart_Handle scriptURL = Dart_ListGetAt(scripts, j);
+            dispatchDidParseSource(libraryId, scriptURL, isolate);
+        }
+    }
+}
+
+Vector<Dart_Isolate> DartPageDebug::isolates()
+{
+    Vector<Dart_Isolate> result;
+    m_isolateMap.copyValues(result);
+    return result;
+}
+
+void DartPageDebug::addListener(ScriptDebugListener* listener)
+{
+    ASSERT(!m_listener);
+    m_listener = listener;
+
+    Vector<Dart_Isolate> iter = isolates();
+    for (Vector<Dart_Isolate>::iterator i = iter.begin(); i != iter.end(); ++i) {
+        Dart_Isolate isolate = *i;
+        DartIsolateScope scope(isolate);
+        DartApiScope apiScope;
+        isolateLoaded();
+    }
+}
+
+void DartPageDebug::removeListener()
+{
+    m_listener = 0;
+    Vector<Dart_Isolate> iter = isolates();
+    for (Vector<Dart_Isolate>::iterator i = iter.begin(); i != iter.end(); ++i) {
+        Dart_Isolate isolate = *i;
+        DartIsolateScope scope(isolate);
+        DartApiScope apiScope;
+        Dart_SetPausedEventHandler(0);
+        Dart_SetExceptionThrownHandler(0);
+        Dart_SetIsolateEventHandler(0);
+        Dart_SetExceptionPauseInfo(kNoPauseOnExceptions);
+    }
+    // FIXME: Remove all breakpoints set by the agent. JavaScript does not
+    // remove the breakpoints either.
+}
+
+void DartPageDebug::unregisterIsolate(Dart_Isolate isolate)
+{
+    clearBreakpointsForIsolate(isolate);
+    m_isolateMap.removeByValue(isolate);
+}
+
+void DartPageDebug::isolateLoaded()
+{
+    if (!m_listener)
+        return;
+
+    Dart_Isolate isolate = Dart_CurrentIsolate();
+    Dart_SetPausedEventHandler(DartScriptDebugServer::pausedEventHandler);
+    Dart_SetExceptionThrownHandler(DartScriptDebugServer::exceptionHandler);
+    Dart_SetIsolateEventHandler(DartScriptDebugServer::isolateEventHandler);
+
+    Dart_ExceptionPauseInfo pauseInfo = calculatePauseInfo(
+        DartScriptDebugServer::shared().pauseOnExceptionState());
+    Dart_SetExceptionPauseInfo(pauseInfo);
+
+    ASSERT(isolate);
+    // FIXME: we should be able to get rid of the V8Scope now that
+    // DartScriptState and ScriptState have been refactored.
+    V8Scope v8Scope(DartDOMData::current(), v8::Debug::GetDebugContext());
+
+    LocalFrame* frame = DartUtilities::domWindowForCurrentIsolate()->frame();
+    DartController* controller = DartController::retrieve(frame);
+    Vector<DartScriptState*> scriptStates;
+    controller->collectScriptStatesForIsolate(isolate, DartUtilities::currentV8Context(), scriptStates);
+    for (size_t i = 0; i< scriptStates.size(); i++)
+        InspectorInstrumentation::didCreateIsolatedContext(frame, scriptStates[i], 0);
+
+    registerIsolateScripts(isolate);
+
+    for (BreakpointMap::iterator it = m_breakpoints.begin(); it != m_breakpoints.end(); ++it) {
+        Dart_Handle ALLOW_UNUSED exception = 0;
+        setBreakpointHelper(it->value, it->key, isolate, exception);
+    }
+}
+
+String DartPageDebug::lookupBreakpointId(intptr_t dartBreakpointId)
+{
+    if (dartBreakpointId > 0) {
+        BreakpointIdMap::iterator it = m_breakpointIdMap.find(dartBreakpointId);
+        if (it != m_breakpointIdMap.end())
+            return it->value;
+    }
+    return "";
+}
+
+DartScriptDebugServer::DartScriptDebugServer()
+    : m_pauseOnExceptionState(DontPauseOnExceptions)
+    , m_breakpointsActivated(true)
+    , m_runningNestedMessageLoop(false)
+    , m_executionState(0)
+    , m_pausedPage(0)
+    , m_clientMessageLoop(0)
+    , m_nextPageId(1)
+{
+}
+
+DartScriptDebugServer::~DartScriptDebugServer()
+{
+    for (DebugDataMap::iterator it = m_pageIdToDebugDataMap.begin(); it != m_pageIdToDebugDataMap.end(); ++it)
+        delete it->value;
+}
+
+DartPageDebug* DartScriptDebugServer::lookupPageDebugForId(const String& id)
+{
+    RefPtr<JSONValue> json = parseJSON(id);
+    ASSERT(json && json->type() == JSONValue::TypeObject);
+    if (json && json->type() == JSONValue::TypeObject) {
+        size_t pageId;
+        bool success = json->asObject()->getNumber("page", &pageId);
+        ASSERT(success);
+        if (success)
+            return m_pageIdToDebugDataMap.get(pageId);
+    }
+    return 0;
+}
+
+DartPageDebug* DartScriptDebugServer::lookupPageDebug(Page* page)
+{
+    ASSERT(page);
+    PageToIdMap::iterator it = m_pageToIdMap.find(page);
+    if (it != m_pageToIdMap.end())
+        return m_pageIdToDebugDataMap.get(it->value);
+
+    size_t pageId = m_nextPageId++;
+    m_pageToIdMap.set(page, pageId);
+    DartPageDebug* pageDebug = new DartPageDebug(page, pageId);
+    m_pageIdToDebugDataMap.set(pageId, pageDebug);
+    return pageDebug;
+}
+
+String DartScriptDebugServer::getScriptId(const String& url, Dart_Isolate isolate)
+{
+    // FIXME: this is a ugly. It would be better to get the domData for the
+    // specified isolate.
+    ASSERT(isolate == Dart_CurrentIsolate());
+    DartPageDebug* pageDebug = lookupPageDebug(DartUtilities::domWindowForCurrentIsolate()->document()->page());
+    ASSERT(pageDebug);
+    if (!pageDebug)
+        return "";
+    return pageDebug->getScriptId(url);
+}
+
+void DartScriptDebugServer::registerIsolate(Dart_Isolate isolate, Page* page)
+{
+    DartIsolateScope scope(isolate);
+    DartApiScope apiScope;
+
+    DartPageDebug* pageDebug = lookupPageDebug(page);
+    pageDebug->registerIsolate(isolate);
+}
+
+// FIXMEDART: we aren't really handling adding and removing breakpoints
+// as new isolates add/remove themselves.
+String DartScriptDebugServer::setBreakpoint(const String& sourceID, const ScriptBreakpoint& scriptBreakpoint, int* actualLineNumber, int* actualColumnNumber, bool interstatementLocation)
+{
+    DartPageDebug* pageDebug = lookupPageDebugForId(sourceID);
+    ASSERT(pageDebug);
+    if (!pageDebug)
+        return "";
+    return pageDebug->setBreakpoint(sourceID, scriptBreakpoint, actualLineNumber, actualColumnNumber, interstatementLocation);
+}
+
+void DartScriptDebugServer::removeBreakpoint(const String& breakpointId)
+{
+    DartPageDebug* pageDebug = lookupPageDebugForId(breakpointId);
+    if (pageDebug) {
+        pageDebug->removeBreakpoint(breakpointId);
+    }
+}
+
+void DartScriptDebugServer::clearBreakpoints()
+{
+    Vector<DartPageDebug*> list = pages();
+    for (Vector<DartPageDebug*>::iterator it = list.begin(); it != list.end(); ++it)
+        (*it)->clearBreakpoints();
+}
+
+void DartScriptDebugServer::setBreakpointsActivated(bool activated)
+{
+    m_breakpointsActivated = activated;
+}
+
+ScriptDebugServer::PauseOnExceptionsState DartScriptDebugServer::pauseOnExceptionsState()
+{
+    return m_pauseOnExceptionState;
+}
+
+void DartScriptDebugServer::setPauseOnExceptionsState(PauseOnExceptionsState pauseOnExceptionState)
+{
+    if (m_pauseOnExceptionState == pauseOnExceptionState)
+        return;
+    m_pauseOnExceptionState = pauseOnExceptionState;
+
+    Dart_ExceptionPauseInfo pauseInfo = calculatePauseInfo(pauseOnExceptionState);
+
+    Vector<Dart_Isolate> iter = isolates();
+    for (Vector<Dart_Isolate>::iterator it = iter.begin(); it != iter.end(); ++it) {
+        DartIsolateScope scope(*it);
+        DartApiScope apiScope;
+        Dart_SetExceptionPauseInfo(pauseInfo);
+    }
+}
+
+void DartScriptDebugServer::setPauseOnNextStatement(bool pause)
+{
+    if (isPaused())
+        return;
+    if (pause) {
+        debugBreak();
+    } else {
+        cancelDebugBreak();
+    }
+}
+
+bool DartScriptDebugServer::canBreakProgram()
+{
+    if (!m_breakpointsActivated)
+        return false;
+
+    // FIXME: what is the dart equivalent of
+    // v8::HandleScope scope(m_isolate);
+    // return !m_isolate->GetCurrentContext().IsEmpty();
+    // ?
+    return true;
+}
+
+void DartScriptDebugServer::breakProgram()
+{
+    if (!canBreakProgram())
+        return;
+
+    // FIXME: determine if this method needs to be implemented for Dart.
+}
+
+void DartScriptDebugServer::continueProgram()
+{
+    if (isPaused())
+        quitMessageLoopOnPause();
+    m_executionState = 0;
+}
+
+void DartScriptDebugServer::stepIntoStatement()
+{
+    ASSERT(isPaused());
+    Dart_SetStepInto();
+    continueProgram();
+}
+
+void DartScriptDebugServer::stepOverStatement(const ActivationFrame& frame)
+{
+    ASSERT(isPaused());
+    Dart_SetStepOver();
+    continueProgram();
+}
+
+void DartScriptDebugServer::stepOutOfFunction(const ActivationFrame& frame)
+{
+    ASSERT(isPaused());
+    Dart_SetStepOut();
+    continueProgram();
+}
+
+bool DartScriptDebugServer::setScriptSource(const String& sourceID, const String& newContent, bool preview, String* error, RefPtr<TypeBuilder::Debugger::SetScriptSourceError>& errorData, StackTrace* newCallFrames, RefPtr<JSONObject>& result)
+{
+    *error = "Dart does not support live editing source code yet.";
+    return false;
+}
+
+bool DartScriptDebugServer::executeSkipPauseRequest(ScriptDebugListener::SkipPauseRequest request, Dart_StackTrace stackTrace)
+{
+    switch (request) {
+    case ScriptDebugListener::NoSkip:
+        return false;
+    case ScriptDebugListener::Continue:
+        return true;
+    case ScriptDebugListener::StepInto:
+    case ScriptDebugListener::StepOut:
+        break;
+    }
+    ASSERT(0);
+    // FIXMEDART: actually do something jacobr JACOBR
+    return true;
+}
+
+StackTrace DartScriptDebugServer::currentCallFrames()
+{
+    return StackTrace(m_executionState);
+}
+
+StackTrace DartScriptDebugServer::currentCallFramesForAsyncStack()
+{
+    // FIXMEDART: implement propertly. These are the regular not Async call frames.
+    return StackTrace(m_executionState);
+}
+
+bool DartScriptDebugServer::isPaused()
+{
+    return !!m_executionState;
+}
+
+void DartScriptDebugServer::clearCompiledScripts()
+{
+    // FIXMEDART: is this meaningful for Dart?
+    // Currently tracking what scripts have been compiled is handled by a
+    // different class.
+}
+
+void DartScriptDebugServer::setPreprocessorSource(const String& preprocessorSource)
+{
+    // FIXMEDART: support calling a preprocessor on all Dart scripts.
+}
+
+DartScriptDebugServer& DartScriptDebugServer::shared()
+{
+    DEFINE_STATIC_LOCAL(DartScriptDebugServer, server, ());
+    return server;
+}
+
+void DartScriptDebugServer::addListener(ScriptDebugListener* listener, Page* page)
+{
+    ScriptController& scriptController = page->mainFrame()->script();
+    if (!scriptController.canExecuteScripts(NotAboutToExecuteScript))
+        return;
+
+    DartPageDebug* pageDebug = lookupPageDebug(page);
+    pageDebug->addListener(listener);
+}
+
+Vector<DartPageDebug*> DartScriptDebugServer::pages()
+{
+    Vector<DartPageDebug*> result;
+    copyValuesToVector(m_pageIdToDebugDataMap, result);
+    return result;
+}
+
+Vector<Dart_Isolate> DartScriptDebugServer::isolates()
+{
+    Vector<Dart_Isolate> result;
+    Vector<DartPageDebug*> allPages = pages();
+    for (Vector<DartPageDebug*>::iterator it = allPages.begin(); it != allPages.end(); ++it) {
+        Vector<Dart_Isolate> forPage = (*it)->isolates();
+        result.appendRange(forPage.begin(), forPage.end());
+    }
+    return result;
+}
+
+bool DartScriptDebugServer::resolveCodeLocation(const Dart_CodeLocation& location, int* line, int* column)
+{
+    // FIXME: cache the results of calling Dart_ScriptGetTokenInfo to improve
+    // performance.
+    Dart_Handle info = Dart_ScriptGetTokenInfo(location.library_id, location.script_url);
+    ASSERT(Dart_IsList(info));
+    intptr_t infoLength = 0;
+    Dart_Handle ALLOW_UNUSED result = Dart_ListLength(info, &infoLength);
+    ASSERT(!Dart_IsError(result));
+    Dart_Handle elem;
+    bool lineStart = true;
+    int currentLineNumber = 0;
+    for (intptr_t i = 0; i < infoLength; i++) {
+        elem = Dart_ListGetAt(info, i);
+        if (Dart_IsNull(elem)) {
+            lineStart = true;
+        } else {
+            ASSERT(Dart_IsInteger(elem));
+            Dart_Handle exception = 0;
+            int64_t value = DartUtilities::toInteger(elem, exception);
+            ASSERT(!exception);
+            if (lineStart) {
+                // Line number.
+                currentLineNumber = value;
+                lineStart = false;
+            } else {
+                // Token offset.
+                if (value == location.token_pos) {
+                    *line = currentLineNumber;
+                    ASSERT(i + 1 < infoLength);
+                    *column = DartUtilities::toInteger(Dart_ListGetAt(info, i + 1), exception);
+                    ASSERT(!exception);
+                    return true;
+                }
+                i++; // skip columnNumber.
+            }
+        }
+    }
+    return false;
+}
+
+void DartScriptDebugServer::removeListener(ScriptDebugListener* listener, Page* page)
+{
+    if (!m_pageToIdMap.contains(page))
+        return;
+
+    if (m_pausedPage == page)
+        continueProgram();
+
+    DartPageDebug* pageDebug = lookupPageDebug(page);
+    if (pageDebug)
+        pageDebug->removeListener();
+}
+
+void DartScriptDebugServer::setClientMessageLoop(PageScriptDebugServer::ClientMessageLoop* clientMessageLoop)
+{
+    m_clientMessageLoop = clientMessageLoop;
+}
+
+void DartScriptDebugServer::runMessageLoopOnPause(Dart_Isolate isolate)
+{
+    LocalFrame* frame = DartUtilities::domWindowForCurrentIsolate()->frame();
+    m_pausedPage = frame->page();
+
+    // Wait for continue or step command.
+    ASSERT(m_clientMessageLoop);
+    if (m_clientMessageLoop)
+        m_clientMessageLoop->run(m_pausedPage);
+
+    DartPageDebug* pageDebug = lookupPageDebug(m_pausedPage);
+    // The listener may have been removed in the nested loop.
+    if (pageDebug && pageDebug->listener())
+        pageDebug->listener()->didContinue();
+
+    m_pausedPage = 0;
+}
+
+void DartScriptDebugServer::quitMessageLoopOnPause()
+{
+    m_clientMessageLoop->quitNow();
+}
+
+bool DartScriptDebugServer::canPreprocess(LocalFrame* frame)
+{
+    // FIXMEDART: support preprocessing Dart source code.
+    return false;
+}
+
+// Source to Source processing iff debugger enabled and it has loaded a preprocessor.
+PassOwnPtr<ScriptSourceCode> DartScriptDebugServer::preprocess(LocalFrame* frame, const ScriptSourceCode& sourceCode)
+{
+    // FIXMEDART: support preprocessing Dart source code.
+    return PassOwnPtr<ScriptSourceCode>();
+}
+
+String DartScriptDebugServer::preprocessEventListener(LocalFrame* frame, const String& source, const String& url, const String& functionName)
+{
+    // We don't support inline event listeners in Dart so this code should
+    // never be executed.
+    ASSERT_NOT_REACHED();
+    return source;
+}
+
+void DartScriptDebugServer::debugBreak()
+{
+    Vector<Dart_Isolate> iter = isolates();
+    for (Vector<Dart_Isolate>::iterator it = iter.begin(); it != iter.end(); ++it) {
+        Dart_Isolate isolate = *it;
+        if (!m_interruptCalled.contains(isolate)) {
+            m_interruptCalled.add(isolate);
+            Dart_InterruptIsolate(isolate);
+        }
+        m_interruptCancelled.remove(isolate);
+    }
+}
+
+void DartScriptDebugServer::cancelDebugBreak()
+{
+    // FIXME: it would be nice if the DartVM provided an API to directly cancel
+    // a debug break call like V8 does.
+    for (HashSet<Dart_Isolate>::iterator it = m_interruptCalled.begin(); it != m_interruptCalled.end(); ++it) {
+        m_interruptCancelled.add(*it);
+    }
+}
+
+Page* DartScriptDebugServer::inferPage(Dart_Isolate isolate)
+{
+    for (DebugDataMap::iterator it = m_pageIdToDebugDataMap.begin(); it != m_pageIdToDebugDataMap.end(); ++it) {
+        DartPageDebug* pageDebug = it->value;
+        if (pageDebug->containsIsolate(isolate)) {
+            return pageDebug->page();
+        }
+    }
+    return 0;
+}
+
+void DartScriptDebugServer::unregisterIsolate(Dart_Isolate isolate, Page* page)
+{
+    m_interruptCalled.remove(isolate);
+    m_interruptCancelled.remove(isolate);
+    if (!page) {
+        // FIXME: We should instead fix the underlying issue where the
+        // reference to the page is lost before we call unregisterIsolate in
+        // some cases.
+        page = inferPage(isolate);
+        ASSERT(page);
+    }
+    DartPageDebug* pageDebug = lookupPageDebug(page);
+    ASSERT(pageDebug);
+    if (pageDebug)
+        pageDebug->unregisterIsolate(isolate);
+}
+
+void DartScriptDebugServer::isolateLoaded()
+{
+    Page* page = DartUtilities::domWindowForCurrentIsolate()->document()->page();
+    if (!page || !instrumentationForPage(page)->inspectorDebuggerAgent())
+        return;
+
+    DartPageDebug* pageDebug = lookupPageDebug(page);
+    if (!pageDebug)
+        return;
+
+    pageDebug->isolateLoaded();
+}
+
+void DartScriptDebugServer::handleDartDebugEvent(Dart_IsolateId isolateId, intptr_t breakpointId, Dart_Handle exception, const Dart_CodeLocation& location)
+{
+    Dart_Isolate isolate = Dart_GetIsolate(isolateId);
+    ASSERT(isolate);
+    Dart_Handle result = 0;
+    Dart_StackTrace stackTrace = 0;
+    result = Dart_GetStackTrace(&stackTrace);
+    ASSERT(!Dart_IsError(result));
+    result = 0;
+    DartPageDebug* pageDebug = lookupPageDebugForCurrentIsolate();
+    if (!pageDebug)
+        return;
+    ScriptDebugListener* listener = pageDebug->listener();
+    if (listener) {
+        DartIsolateScope scope(isolate);
+        DartApiScope apiScope;
+        ScriptCallFrame topFrame = DartUtilities::getTopFrame(stackTrace, result);
+        if (!result) {
+            if (exception) {
+                if (executeSkipPauseRequest(listener->shouldSkipExceptionPause(topFrame), stackTrace))
+                    return;
+            } else {
+                ScriptDebugListener::SkipPauseRequest skipRequest;
+                if (breakpointId != ILLEGAL_BREAKPOINT_ID)
+                    skipRequest = listener->shouldSkipBreakpointPause(topFrame);
+                else
+                    skipRequest = listener->shouldSkipStepPause(topFrame);
+                if (executeSkipPauseRequest(skipRequest, stackTrace))
+                    return;
+            }
+        }
+        handleProgramBreak(isolate, stackTrace, breakpointId, exception, location);
+    }
+}
+
+DartPageDebug* DartScriptDebugServer::lookupPageDebugForCurrentIsolate()
+{
+    Page* page = DartUtilities::domWindowForCurrentIsolate()->document()->page();
+    return lookupPageDebug(page);
+}
+
+void DartScriptDebugServer::handleProgramBreak(Dart_Isolate isolate, Dart_StackTrace stackTrace, intptr_t dartBreakpointId, Dart_Handle exception, const Dart_CodeLocation& location)
+{
+    ASSERT(isolate == Dart_CurrentIsolate());
+    // Don't allow nested breaks.
+    if (isPaused())
+        return;
+
+    DartPageDebug* pageDebug = lookupPageDebugForCurrentIsolate();
+    if (!pageDebug)
+        return;
+    ScriptDebugListener* listener = pageDebug->listener();
+
+    if (!listener)
+        return;
+
+    Vector<String> breakpointIds;
+    breakpointIds.append(pageDebug->lookupBreakpointId(dartBreakpointId));
+    m_executionState = stackTrace;
+    // FIXME: remove call to DartHandleProxy once ScriptValue is refactored.
+    listener->didPause(DartUtilities::currentScriptState(), currentCallFrames(), exception ? ScriptValue(DartHandleProxy::create(exception), DartUtilities::currentV8Context()->GetIsolate()) : ScriptValue(), breakpointIds);
+
+    m_runningNestedMessageLoop = true;
+    runMessageLoopOnPause(isolate);
+    m_runningNestedMessageLoop = false;
+}
+
+void DartScriptDebugServer::pausedEventHandler(Dart_IsolateId isolateId, intptr_t breakpointId, const Dart_CodeLocation& location)
+{
+    DartScriptDebugServer::shared().handleDartDebugEvent(isolateId, breakpointId, 0, location);
+}
+
+void DartScriptDebugServer::exceptionHandler(Dart_IsolateId isolateId, Dart_Handle exception, Dart_StackTrace trace)
+{
+    DartScriptDebugServer::shared().handleException(isolateId, exception, trace);
+}
+
+void DartScriptDebugServer::isolateEventHandler(Dart_IsolateId isolateId, Dart_IsolateEvent kind)
+{
+    if (kind == kInterrupted) {
+        DartScriptDebugServer::shared().handleInterrupted(isolateId);
+    }
+}
+
+void DartScriptDebugServer::handleInterrupted(Dart_IsolateId isolateId)
+{
+    Dart_Isolate isolate = Dart_GetIsolate(isolateId);
+
+    if (isolate) {
+        ASSERT(isolate == Dart_CurrentIsolate());
+        if (!m_interruptCalled.contains(isolate)) {
+            return;
+        }
+
+        m_interruptCalled.remove(isolate);
+        if (m_interruptCancelled.contains(isolate)) {
+            m_interruptCancelled.remove(isolate);
+            return;
+        }
+
+        // FIXME: this is a bit of a hack. V8 was also set to pause on the next
+        // code execution. If it attempts to pause while in the middle of
+        // internal V8 debugger logic it will crash so before we do anything we
+        // need to cancel the pending pause sent to V8.
+        // Perhaps it would be slightly less hacky to send a message to
+        // ScriptDebugServer instructing it to cancel pausing V8.
+        v8::Debug::CancelDebugBreak(DartUtilities::currentV8Context()->GetIsolate());
+
+        // The user really wants to be paused at the start of the first line of
+        // the Dart method not at the method invocation itself. Otherwise,
+        // stepping to the next call steps out of the executing Dart code
+        // which is not what the user expects.
+        Dart_SetStepInto();
+        continueProgram();
+    }
+}
+
+void DartScriptDebugServer::handleException(Dart_IsolateId isolateId, Dart_Handle exception, Dart_StackTrace trace)
+{
+    Dart_Isolate isolate = Dart_GetIsolate(isolateId);
+    ASSERT(isolate);
+    Dart_CodeLocation location;
+    Dart_Handle ALLOW_UNUSED result;
+    Dart_ActivationFrame frame;
+    result = Dart_GetActivationFrame(trace, 0, &frame);
+    ASSERT(!Dart_IsError(result));
+    result = Dart_ActivationFrameGetLocation(frame, 0, 0, &location);
+    ASSERT(!Dart_IsError(result));
+    handleProgramBreak(isolate, trace, ILLEGAL_BREAKPOINT_ID, exception, location);
+}
+
+void DartScriptDebugServer::runScript(ScriptState* scriptState, const String& scriptId, ScriptValue* result, bool* wasThrown, String* exceptionMessage)
+{
+}
+
+UnifiedScriptDebugServer::UnifiedScriptDebugServer(DartScriptDebugServer* dartScriptDebugServer, PageScriptDebugServer* scriptDebugServer)
+{
+    m_v8 = scriptDebugServer;
+    m_dart = dartScriptDebugServer;
+}
+
+UnifiedScriptDebugServer& UnifiedScriptDebugServer::shared()
+{
+    DEFINE_STATIC_LOCAL(UnifiedScriptDebugServer, server, (&DartScriptDebugServer::shared(), &PageScriptDebugServer::shared()));
+    return server;
+}
+
+String UnifiedScriptDebugServer::setBreakpoint(const String& sourceID, const ScriptBreakpoint& scriptBreakpoint, int* actualLineNumber, int* actualColumnNumber, bool interstatementLocation)
+{
+    if (isDartSourceID(sourceID))
+        return m_dart->setBreakpoint(sourceID, scriptBreakpoint, actualLineNumber, actualColumnNumber, interstatementLocation);
+    return m_v8->setBreakpoint(sourceID, scriptBreakpoint, actualLineNumber, actualColumnNumber, interstatementLocation);
+}
+
+void UnifiedScriptDebugServer::removeBreakpoint(const String& breakpointId)
+{
+    if (isDartBreakpointId(breakpointId))
+        m_dart->removeBreakpoint(breakpointId);
+    else
+        m_v8->removeBreakpoint(breakpointId);
+}
+
+void UnifiedScriptDebugServer::clearBreakpoints()
+{
+    m_v8->clearBreakpoints();
+    m_dart->clearBreakpoints();
+}
+
+void UnifiedScriptDebugServer::setBreakpointsActivated(bool activated)
+{
+    m_v8->setBreakpointsActivated(activated);
+    m_dart->setBreakpointsActivated(activated);
+}
+
+ScriptDebugServer::PauseOnExceptionsState UnifiedScriptDebugServer::pauseOnExceptionsState()
+{
+    // Assume Dart and V8 always have a consistent value for
+    // pauseOnExceptionsState.
+    return m_v8->pauseOnExceptionsState();
+}
+
+void UnifiedScriptDebugServer::setPauseOnExceptionsState(ScriptDebugServer::PauseOnExceptionsState pauseOnExceptionsState)
+{
+    m_dart->setPauseOnExceptionsState(pauseOnExceptionsState);
+    m_v8->setPauseOnExceptionsState(pauseOnExceptionsState);
+}
+
+void UnifiedScriptDebugServer::setPauseOnNextStatement(bool pause)
+{
+    if (isPaused()) {
+        return;
+    }
+    m_v8->setPauseOnNextStatement(pause);
+    m_dart->setPauseOnNextStatement(pause);
+}
+
+bool UnifiedScriptDebugServer::canBreakProgram()
+{
+    return m_v8->canBreakProgram() || m_dart->canBreakProgram();
+}
+
+void UnifiedScriptDebugServer::breakProgram()
+{
+    if (m_v8->canBreakProgram())
+        m_v8->breakProgram();
+    if (m_dart->canBreakProgram())
+        m_dart->breakProgram();
+}
+
+void UnifiedScriptDebugServer::continueProgram()
+{
+    m_v8->continueProgram();
+    m_dart->continueProgram();
+}
+
+void UnifiedScriptDebugServer::stepIntoStatement()
+{
+    if (m_v8->isPaused())
+        m_v8->stepIntoStatement();
+    else
+        m_dart->stepIntoStatement();
+}
+
+void UnifiedScriptDebugServer::stepOverStatement(const ActivationFrame& frame)
+{
+    if (m_v8->isPaused())
+        m_v8->stepOverStatement(frame);
+    else
+        m_dart->stepOverStatement(frame);
+}
+
+void UnifiedScriptDebugServer::stepOutOfFunction(const ActivationFrame& frame)
+{
+    if (m_v8->isPaused())
+        m_v8->stepOutOfFunction(frame);
+    else
+        m_dart->stepOutOfFunction(frame);
+}
+
+bool UnifiedScriptDebugServer::isDartSourceID(const String& sourceID)
+{
+    // FIXMEDART: find a cleaner solution.
+    return sourceID.startsWith(String("{\"dartScript"));
+}
+
+bool UnifiedScriptDebugServer::isDartBreakpointId(const String& breakpointId)
+{
+    // FIXMEDART: find a cleaner solution.
+    return breakpointId.startsWith(String("{\"dartBreakpoint"));
+}
+
+bool UnifiedScriptDebugServer::setScriptSource(const String& sourceID, const String& newContent, bool preview, String* error, RefPtr<TypeBuilder::Debugger::SetScriptSourceError>& errorBuilder, StackTrace* newCallFrames, RefPtr<JSONObject>& result)
+{
+    if (isDartSourceID(sourceID))
+        return m_dart->setScriptSource(sourceID, newContent, preview, error, errorBuilder, newCallFrames, result);
+    return m_v8->setScriptSource(sourceID, newContent, preview, error, errorBuilder, newCallFrames, result);
+}
+
+StackTrace UnifiedScriptDebugServer::currentCallFrames()
+{
+    // FIXMEDART: we need to figure out how to interleave stack traces where possible.
+    StackTrace v8StackTrace = m_v8->currentCallFrames();
+    if (!v8StackTrace.isNull())
+        return v8StackTrace;
+    return m_dart->currentCallFrames();
+}
+
+StackTrace UnifiedScriptDebugServer::currentCallFramesForAsyncStack()
+{
+    // FIXMEDART: we need to figure out how to interleave stack traces where possible.
+    StackTrace v8StackTrace = m_v8->currentCallFramesForAsyncStack();
+    if (!v8StackTrace.isNull())
+        return v8StackTrace;
+    return m_dart->currentCallFramesForAsyncStack();
+}
+
+
+bool UnifiedScriptDebugServer::isPaused()
+{
+    return m_v8->isPaused() || m_dart->isPaused();
+}
+
+bool UnifiedScriptDebugServer::runningNestedMessageLoop()
+{
+    return m_dart->runningNestedMessageLoop() || m_v8->runningNestedMessageLoop();
+}
+
+void UnifiedScriptDebugServer::clearCompiledScripts()
+{
+    m_v8->clearCompiledScripts();
+    m_dart->clearCompiledScripts();
+}
+
+void UnifiedScriptDebugServer::setPreprocessorSource(const String& script)
+{
+    m_v8->setPreprocessorSource(script);
+    m_dart->setPreprocessorSource(script);
+}
+
+void UnifiedScriptDebugServer::preprocessBeforeCompile(const v8::Debug::EventDetails& eventDetails)
+{
+    m_v8->preprocessBeforeCompile(eventDetails);
+    // FIXMEDART: tweak the signature and call for dart.
+}
+
+PassOwnPtr<ScriptSourceCode> UnifiedScriptDebugServer::preprocess(LocalFrame* frame, const ScriptSourceCode& scriptSourceCode)
+{
+    // FIXME: how do we know whether to preprocess with Dart or V8?
+    return m_v8->preprocess(frame, scriptSourceCode);
+}
+
+void UnifiedScriptDebugServer::addListener(ScriptDebugListener* listener, Page* page)
+{
+    m_v8->addListener(listener, page);
+    m_dart->addListener(listener, page);
+}
+
+void UnifiedScriptDebugServer::removeListener(ScriptDebugListener* listener, Page* page)
+{
+    m_v8->removeListener(listener, page);
+    m_dart->removeListener(listener, page);
+}
+
+String UnifiedScriptDebugServer::preprocessEventListener(LocalFrame* frame, const String& source, const String& url, const String& functionName)
+{
+    // FIXME: how do we know whether to preprocess with Dart or V8?
+    return m_v8->preprocessEventListener(frame, source, url, functionName);
+}
+
+void UnifiedScriptDebugServer::runScript(ScriptState* scriptState, const String& scriptId, ScriptValue* result, bool* wasThrown, String* exceptionMessage)
+{
+    // FIXME: support runScript for Dart as well.
+    m_v8->runScript(scriptState, scriptId, result, wasThrown, exceptionMessage);
+}
+
+}