[inspector] added creation frame for async call chains for promises

src/inspector/v8-debugger.cc

Index: src/inspector/v8-debugger.cc
diff --git a/src/inspector/v8-debugger.cc b/src/inspector/v8-debugger.cc
index 8fa5245b3557a844245e7607d9f4e3d83930f07c..dbea10ac5ae922a6f9abee2e5cc31a8b1c3097cd 100644
--- a/src/inspector/v8-debugger.cc
+++ b/src/inspector/v8-debugger.cc
@@ -858,9 +858,30 @@ void V8Debugger::setAsyncCallStackDepth(V8DebuggerAgentImpl* agent, int depth) {
   if (!maxAsyncCallStackDepth) allAsyncTasksCanceled();
 }
 
+void V8Debugger::registerAsyncTaskIfNeeded(void* task) {
+  if (m_taskToId.find(task) != m_taskToId.end()) return;
+
+  int id = ++m_lastTaskId;
+  m_taskToId[task] = id;
+  m_idToTask[id] = task;
+  if (static_cast<int>(m_idToTask.size()) > m_maxAsyncCallStacks) {
+    void* taskToRemove = m_idToTask.begin()->second;
+    asyncTaskCanceled(taskToRemove);
+  }
+}
+
 void V8Debugger::asyncTaskCreated(void* task, void* parentTask) {
   if (!m_maxAsyncCallStackDepth) return;
   if (parentTask) m_parentTask[task] = parentTask;
+  v8::HandleScope scope(m_isolate);
+  // We don't need to pass context group id here because we gets
+  // this callback from V8 for promise events only.
+  std::unique_ptr<V8StackTraceImpl> chain =

[dgozman, 2017/01/24 23:57:44]

chain -> creationStack

[kozy, 2017/01/25 00:45:43]

Done.

+      V8StackTraceImpl::capture(this, 0, 1, String16());

[dgozman, 2017/01/24 23:57:44]

Let's comment that passing 1 here force no async chain for the new stack, which
allows us to not grow exponentially.

[kozy, 2017/01/25 00:45:43]

Done.

+  if (chain && !chain->isEmpty()) {
+    m_asyncTaskCreationStacks[task] = std::move(chain);
+    registerAsyncTaskIfNeeded(task);
+  }
 }
 
 void V8Debugger::asyncTaskScheduled(const StringView& taskName, void* task,
@@ -883,13 +904,7 @@ void V8Debugger::asyncTaskScheduled(const String16& taskName, void* task,
   if (chain) {
     m_asyncTaskStacks[task] = std::move(chain);
     if (recurring) m_recurringTasks.insert(task);
-    int id = ++m_lastTaskId;
-    m_taskToId[task] = id;
-    m_idToTask[id] = task;
-    if (static_cast<int>(m_idToTask.size()) > m_maxAsyncCallStacks) {
-      void* taskToRemove = m_idToTask.begin()->second;
-      asyncTaskCanceled(taskToRemove);
-    }
+    registerAsyncTaskIfNeeded(task);
   }
 }
 
@@ -898,6 +913,7 @@ void V8Debugger::asyncTaskCanceled(void* task) {
   m_asyncTaskStacks.erase(task);
   m_recurringTasks.erase(task);
   m_parentTask.erase(task);
+  m_asyncTaskCreationStacks.erase(task);
   auto it = m_taskToId.find(task);
   if (it == m_taskToId.end()) return;
   m_idToTask.erase(it->second);
@@ -920,6 +936,10 @@ void V8Debugger::asyncTaskStarted(void* task) {
   std::unique_ptr<V8StackTraceImpl> stack;
   if (stackIt != m_asyncTaskStacks.end() && stackIt->second)
     stack = stackIt->second->cloneImpl();
+  auto itCreation = m_asyncTaskCreationStacks.find(task);
+  if (stack && itCreation != m_asyncTaskCreationStacks.end()) {
+    stack->setCreation(itCreation->second->cloneImpl());
+  }
   m_currentStacks.push_back(std::move(stack));
 }
 
@@ -943,6 +963,7 @@ void V8Debugger::allAsyncTasksCanceled() {
   m_currentStacks.clear();
   m_currentTasks.clear();
   m_parentTask.clear();
+  m_asyncTaskCreationStacks.clear();
   m_idToTask.clear();
   m_taskToId.clear();
   m_lastTaskId = 0;