Support tasks injection into a running VM.

test/cctest/test-debug.cc

 // Copyright 2012 the V8 project authors. 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
@@ skipping 7378 matching lines @@
   CHECK_EQ(1, CountNativeContexts());
 
   v8::Debug::SetDebugEventListener(NopListener);
   CompileRun("debugger;");
   CHECK_EQ(2, CountNativeContexts());
 
   v8::Debug::SetDebugEventListener(NULL);
 }
 
 
+class DelayedTask : public v8::base::Thread {
+ public:
+  DelayedTask(v8::Isolate* isolate, v8::Debug::Task* task, int delay_ms)
+      : Thread(Options("DelayedTask")),
+        isolate_(isolate),
+        task_(task),
+        delay_ms_(delay_ms) {}
+  void Run() override {
+    v8::base::OS::Sleep(delay_ms_);
+    v8::Debug::BreakAndRun(isolate_, task_);
+    task_ = NULL;
+  }
+
+ private:
+  v8::Isolate* isolate_;
+  v8::Debug::Task* task_;
+  int delay_ms_;
+};
+
+
+class StopExecutionTask : public v8::Debug::Task {
+ public:
+  explicit StopExecutionTask(LocalContext& context) : context_(context) {}
+  void Run() override {
+    context_->Global()->Set(v8_str("stop"), v8::True(context_->GetIsolate()));
+  }
+
+ private:
+  LocalContext& context_;
+};
+
+
+TEST(RunTaskWhileLooping) {
+  LocalContext env;
+  v8::HandleScope scope(env->GetIsolate());
+
+  v8::Debug::Task* task = new StopExecutionTask(env);
+  DelayedTask delayed_task(env->GetIsolate(), task, 10);

[yurys, 2014/12/17 15:29:09]

Please add a comment on why we need the delay.

+  CompileRun("var stop = false;");
+  delayed_task.Start();
+  CompileRun("while (!stop) {}");
+}
+
+
 TEST(LiveEditEnabled) {
   v8::internal::FLAG_allow_natives_syntax = true;
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
   v8::Debug::SetLiveEditEnabled(env->GetIsolate(), true);
   CompileRun("%LiveEditCompareStrings('', '')");
 }
 
 
 TEST(LiveEditDisabled) {
@@ skipping 263 matching lines @@
       "let y = 2;               \n"
       "debugger;                \n"
       "x * y",
       30);
   ExpectInt32(
       "x = 1; y = 2; \n"
       "debugger;"
       "x * y",
       30);
 }