DevTools: Capture async stacks for event listeners.

Source/core/inspector/AsyncCallStackTracker.cpp

Index: Source/core/inspector/AsyncCallStackTracker.cpp
diff --git a/Source/core/inspector/AsyncCallStackTracker.cpp b/Source/core/inspector/AsyncCallStackTracker.cpp
index 89d21b2452a3474eed3556fee4a124f9f464094d..841c94667395ff8770fe72ba997c60f5fc033a48 100644
--- a/Source/core/inspector/AsyncCallStackTracker.cpp
+++ b/Source/core/inspector/AsyncCallStackTracker.cpp
@@ -33,12 +33,19 @@
 
 #include "core/dom/ContextLifecycleObserver.h"
 #include "core/dom/ExecutionContext.h"
+#include "core/events/EventTarget.h"
+#include "core/events/RegisteredEventListener.h"
+#include "wtf/text/StringBuilder.h"
 
 namespace WebCore {
 
 class AsyncCallStackTracker::ExecutionContextData : public ContextLifecycleObserver {
     WTF_MAKE_FAST_ALLOCATED;
 public:
+    typedef std::pair<RegisteredEventListener, RefPtr<AsyncCallChain> > EventListenerAsyncCallChain;
+    typedef Vector<EventListenerAsyncCallChain, 1> EventListenerAsyncCallChainVector;
+    typedef HashMap<AtomicString, EventListenerAsyncCallChainVector> EventListenerAsyncCallChainVectorHashMap;
+
     ExecutionContextData(AsyncCallStackTracker* tracker, ExecutionContext* executionContext)
         : ContextLifecycleObserver(executionContext)
         , m_tracker(tracker)
@@ -54,12 +61,56 @@ public:
         delete self;
     }
 
-private:
-    friend class AsyncCallStackTracker;
+    void addEventListenerData(EventTarget* eventTarget, const AtomicString& eventType, const EventListenerAsyncCallChain& item)
+    {
+        HashMap<EventTarget*, EventListenerAsyncCallChainVectorHashMap>::iterator it = m_eventTargetCallChains.find(eventTarget);
+        if (it == m_eventTargetCallChains.end())
+            it = m_eventTargetCallChains.set(eventTarget, EventListenerAsyncCallChainVectorHashMap()).iterator;
+        EventListenerAsyncCallChainVectorHashMap& map = it->value;
+        EventListenerAsyncCallChainVectorHashMap::iterator it2 = map.find(eventType);
+        if (it2 == map.end())
+            it2 = map.set(eventType, EventListenerAsyncCallChainVector()).iterator;
+        it2->value.append(item);
+    }
+
+    void removeEventListenerData(EventTarget* eventTarget, const AtomicString& eventType, const RegisteredEventListener& item)
+    {
+        findEventListenerData(eventTarget, eventType, item, true);
+    }
+
+    PassRefPtr<AsyncCallChain> findEventListenerData(EventTarget* eventTarget, const AtomicString& eventType, const RegisteredEventListener& item, bool remove = false)
+    {
+        HashMap<EventTarget*, EventListenerAsyncCallChainVectorHashMap>::iterator it = m_eventTargetCallChains.find(eventTarget);
+        if (it == m_eventTargetCallChains.end())
+            return 0;
+        EventListenerAsyncCallChainVectorHashMap& map = it->value;
+        EventListenerAsyncCallChainVectorHashMap::iterator it2 = map.find(eventType);
+        if (it2 == map.end())
+            return 0;
+        RefPtr<AsyncCallChain> result;
+        EventListenerAsyncCallChainVector& vector = it2->value;
+        for (size_t i = 0; i < vector.size(); ++i) {
+            if (vector[i].first == item) {
+                result = vector[i].second;
+                if (remove) {
+                    vector.remove(i);
+                    if (vector.isEmpty())
+                        map.remove(it2);
+                    if (map.isEmpty())
+                        m_eventTargetCallChains.remove(it);
+                }
+                break;
+            }
+        }
+        return result.release();
+    }
+
+public:
     AsyncCallStackTracker* m_tracker;
     HashSet<int> m_intervalTimerIds;
     HashMap<int, RefPtr<AsyncCallChain> > m_timerCallChains;
     HashMap<int, RefPtr<AsyncCallChain> > m_animationFrameCallChains;
+    HashMap<EventTarget*, EventListenerAsyncCallChainVectorHashMap> m_eventTargetCallChains;
 };
 
 AsyncCallStackTracker::AsyncCallStack::AsyncCallStack(const String& description, const ScriptValue& callFrames)
@@ -113,7 +164,8 @@ void AsyncCallStackTracker::didInstallTimer(ExecutionContext* context, int timer
 void AsyncCallStackTracker::didRemoveTimer(ExecutionContext* context, int timerId)
 {
     ASSERT(context);
-    if (!isEnabled() || timerId <= 0)
+    ASSERT(isEnabled());
+    if (timerId <= 0)
         return;
     ExecutionContextData* data = m_executionContextDataMap.get(context);
     if (!data)
@@ -125,17 +177,16 @@ void AsyncCallStackTracker::didRemoveTimer(ExecutionContext* context, int timerI
 void AsyncCallStackTracker::willFireTimer(ExecutionContext* context, int timerId)
 {
     ASSERT(context);
-    if (!isEnabled())
-        return;
+    ASSERT(isEnabled());
     ASSERT(timerId > 0);
     ASSERT(!m_currentAsyncCallChain);
     ExecutionContextData* data = m_executionContextDataMap.get(context);
     if (!data)
         return;
     if (data->m_intervalTimerIds.contains(timerId))
-        m_currentAsyncCallChain = data->m_timerCallChains.get(timerId);
+        setCurrentAsyncCallChain(data->m_timerCallChains.get(timerId));
     else
-        m_currentAsyncCallChain = data->m_timerCallChains.take(timerId);
+        setCurrentAsyncCallChain(data->m_timerCallChains.take(timerId));
 }
 
 void AsyncCallStackTracker::didRequestAnimationFrame(ExecutionContext* context, int callbackId, const ScriptValue& callFrames)
@@ -154,7 +205,8 @@ void AsyncCallStackTracker::didRequestAnimationFrame(ExecutionContext* context,
 void AsyncCallStackTracker::didCancelAnimationFrame(ExecutionContext* context, int callbackId)
 {
     ASSERT(context);
-    if (!isEnabled() || callbackId <= 0)
+    ASSERT(isEnabled());
+    if (callbackId <= 0)
         return;
     if (ExecutionContextData* data = m_executionContextDataMap.get(context))
         data->m_animationFrameCallChains.remove(callbackId);
@@ -163,28 +215,86 @@ void AsyncCallStackTracker::didCancelAnimationFrame(ExecutionContext* context, i
 void AsyncCallStackTracker::willFireAnimationFrame(ExecutionContext* context, int callbackId)
 {
     ASSERT(context);
-    if (!isEnabled())
-        return;
+    ASSERT(isEnabled());
     ASSERT(callbackId > 0);
     ASSERT(!m_currentAsyncCallChain);
     if (ExecutionContextData* data = m_executionContextDataMap.get(context))
-        m_currentAsyncCallChain = data->m_animationFrameCallChains.take(callbackId);
+        setCurrentAsyncCallChain(data->m_animationFrameCallChains.take(callbackId));
+}
+
+void AsyncCallStackTracker::didAddEventListener(EventTarget* eventTarget, const AtomicString& eventType, EventListener* listener, bool useCapture, const ScriptValue& callFrames)
+{
+    ASSERT(eventTarget->executionContext());
+    ASSERT(isEnabled());
+    if (!validateCallFrames(callFrames))
+        return;
+
+    StringBuilder description;
+    description.append(eventTarget->interfaceName());
+    if (!description.isEmpty())
+        description.append(".");
+    if (listener->isAttribute()) {
+        description.append("on");
+        description.append(eventType);
+    } else {
+        description.append("addEventListener(\"");
+        description.append(eventType);
+        description.append("\")");
+    }
+
+    ExecutionContextData* data = createContextDataIfNeeded(eventTarget->executionContext());
+    data->addEventListenerData(eventTarget, eventType, std::make_pair(RegisteredEventListener(listener, useCapture), createAsyncCallChain(description.toString(), callFrames)));
+}
+
+void AsyncCallStackTracker::didRemoveEventListener(EventTarget* eventTarget, const AtomicString& eventType, EventListener* listener, bool useCapture)
+{
+    ASSERT(eventTarget->executionContext());
+    ASSERT(isEnabled());
+    if (ExecutionContextData* data = m_executionContextDataMap.get(eventTarget->executionContext()))
+        data->removeEventListenerData(eventTarget, eventType, RegisteredEventListener(listener, useCapture));
+}
+
+void AsyncCallStackTracker::didRemoveAllEventListeners(EventTarget* eventTarget)
+{
+    ASSERT(eventTarget->executionContext());
+    ASSERT(isEnabled());
+    if (ExecutionContextData* data = m_executionContextDataMap.get(eventTarget->executionContext()))
+        data->m_eventTargetCallChains.remove(eventTarget);
+}
+
+void AsyncCallStackTracker::willHandleEvent(EventTarget* eventTarget, const AtomicString& eventType, EventListener* listener, bool useCapture)
+{
+    ASSERT(eventTarget->executionContext());
+    ASSERT(isEnabled());
+    if (ExecutionContextData* data = m_executionContextDataMap.get(eventTarget->executionContext()))
+        setCurrentAsyncCallChain(data->findEventListenerData(eventTarget, eventType, RegisteredEventListener(listener, useCapture)));
 }
 
 void AsyncCallStackTracker::didFireAsyncCall()
 {
-    m_currentAsyncCallChain = 0;
+    setCurrentAsyncCallChain(0);
 }
 
 PassRefPtr<AsyncCallStackTracker::AsyncCallChain> AsyncCallStackTracker::createAsyncCallChain(const String& description, const ScriptValue& callFrames)
 {
-    ASSERT(isEnabled());
     RefPtr<AsyncCallChain> chain = adoptRef(m_currentAsyncCallChain ? new AsyncCallStackTracker::AsyncCallChain(*m_currentAsyncCallChain) : new AsyncCallStackTracker::AsyncCallChain());
     ensureMaxAsyncCallChainDepth(chain.get(), m_maxAsyncCallStackDepth - 1);
     chain->m_callStacks.prepend(adoptRef(new AsyncCallStackTracker::AsyncCallStack(description, callFrames)));
     return chain.release();
 }
 
+void AsyncCallStackTracker::setCurrentAsyncCallChain(PassRefPtr<AsyncCallChain> chain)
+{
+    if (m_currentAsyncCallChain) {
+        m_nestedAsyncCallCount += chain ? 1 : -1;
+        if (!m_nestedAsyncCallCount)
+            m_currentAsyncCallChain = 0;
+    } else if (chain) {
+        m_currentAsyncCallChain = chain;
+        m_nestedAsyncCallCount = 1;
+    }
+}
+
 void AsyncCallStackTracker::ensureMaxAsyncCallChainDepth(AsyncCallChain* chain, unsigned maxDepth)
 {
     while (chain->m_callStacks.size() > maxDepth)
@@ -209,6 +319,7 @@ AsyncCallStackTracker::ExecutionContextData* AsyncCallStackTracker::createContex
 void AsyncCallStackTracker::clear()
 {
     m_currentAsyncCallChain = 0;
+    m_nestedAsyncCallCount = 0;
     ExecutionContextDataMap copy;
     m_executionContextDataMap.swap(copy);
     for (ExecutionContextDataMap::const_iterator it = copy.begin(); it != copy.end(); ++it)