From 74fa2c809d7727d3ff792b7f29abd5a797be1095 Mon Sep 17 00:00:00 2001
From: Cheng Zhao <zcbenz@gmail.com>
Date: Fri, 7 Aug 2015 15:18:33 +0800
Subject: [PATCH] Make every JS function call is wrapped with V8RecursionScope

---
 atom/common/event_emitter_caller.cc | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/atom/common/event_emitter_caller.cc b/atom/common/event_emitter_caller.cc
index 3dbdc9db956..68c48217a36 100644
--- a/atom/common/event_emitter_caller.cc
+++ b/atom/common/event_emitter_caller.cc
@@ -4,15 +4,33 @@
 
 #include "atom/common/event_emitter_caller.h"
 
+#include "base/memory/scoped_ptr.h"
+#include "third_party/WebKit/public/web/WebScopedMicrotaskSuppression.h"
+
 #include "atom/common/node_includes.h"
 
 namespace mate {
 
 namespace internal {
 
+namespace {
+
+// Returns whether current process is browser process, currently we detect it
+// by checking whether current has used V8 Lock, but it might be a bad idea.
+inline bool IsBrowserProcess() {
+  return v8::Locker::IsActive();
+}
+
+}  // namespace
+
 v8::Local<v8::Value> CallEmitWithArgs(v8::Isolate* isolate,
                                       v8::Local<v8::Object> obj,
                                       ValueVector* args) {
+  // Perform microtask checkpoint after running JavaScript.
+  scoped_ptr<blink::WebScopedRunV8Script> script_scope(
+      IsBrowserProcess() ? nullptr : new blink::WebScopedRunV8Script(isolate));
+  // Use node::MakeCallback to call the callback, and it will also run pending
+  // tasks in Node.js.
   return node::MakeCallback(
       isolate, obj, "emit", args->size(), &args->front());
 }