Introduce MicrotasksCompletedCallback.

test/cctest/test-api.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 21015 matching lines @@
   TryCatch try_catch(isolate);
   CompileRun("1+1;");
   CHECK(!try_catch.HasCaught());
   CHECK_EQ(1,
            CompileRun("exception1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(1,
            CompileRun("exception2Calls")->Int32Value(env.local()).FromJust());
 }
 
 
+uint8_t microtasks_completed_callback_count = 0;
+
+
+static void MicrotasksCompletedCallback(v8::Isolate* isolate) {
+  ++microtasks_completed_callback_count;
+}
+
+
 TEST(SetAutorunMicrotasks) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
+  env->GetIsolate()->AddMicrotasksCompletedCallback(
+      &MicrotasksCompletedCallback);
   CompileRun(
       "var ext1Calls = 0;"
       "var ext2Calls = 0;");
   CompileRun("1+1;");
   CHECK_EQ(0, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(0, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(0u, microtasks_completed_callback_count);
 
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskOne).ToLocalChecked());
   CompileRun("1+1;");
   CHECK_EQ(1, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(0, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(1u, microtasks_completed_callback_count);
 
   env->GetIsolate()->SetAutorunMicrotasks(false);
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskOne).ToLocalChecked());
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskTwo).ToLocalChecked());
   CompileRun("1+1;");
   CHECK_EQ(1, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(0, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(1u, microtasks_completed_callback_count);
 
   env->GetIsolate()->RunMicrotasks();
   CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(1, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(2u, microtasks_completed_callback_count);
 
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskTwo).ToLocalChecked());
   CompileRun("1+1;");
   CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(1, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(2u, microtasks_completed_callback_count);
 
   env->GetIsolate()->RunMicrotasks();
   CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(2, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(3u, microtasks_completed_callback_count);
 
   env->GetIsolate()->SetAutorunMicrotasks(true);
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskTwo).ToLocalChecked());
   CompileRun("1+1;");
   CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(3, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(4u, microtasks_completed_callback_count);
 
   env->GetIsolate()->EnqueueMicrotask(
       Function::New(env.local(), MicrotaskTwo).ToLocalChecked());
   {
     v8::Isolate::SuppressMicrotaskExecutionScope scope(env->GetIsolate());
     CompileRun("1+1;");
     CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
     CHECK_EQ(3, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+    CHECK_EQ(4u, microtasks_completed_callback_count);
   }
 
   CompileRun("1+1;");
   CHECK_EQ(2, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
   CHECK_EQ(4, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(5u, microtasks_completed_callback_count);
+
+  env->GetIsolate()->RemoveMicrotasksCompletedCallback(
+      &MicrotasksCompletedCallback);
+  env->GetIsolate()->EnqueueMicrotask(
+      Function::New(env.local(), MicrotaskOne).ToLocalChecked());
+  CompileRun("1+1;");
+  CHECK_EQ(3, CompileRun("ext1Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(4, CompileRun("ext2Calls")->Int32Value(env.local()).FromJust());
+  CHECK_EQ(5u, microtasks_completed_callback_count);
 }
 
 
 TEST(RunMicrotasksWithoutEnteringContext) {
   v8::Isolate* isolate = CcTest::isolate();
   HandleScope handle_scope(isolate);
   isolate->SetAutorunMicrotasks(false);
   Local<Context> context = Context::New(isolate);
   {
     Context::Scope context_scope(context);
@@ skipping 3863 matching lines @@
   CHECK(proxy->GetTarget()->SameValue(target));
   CHECK(proxy->GetHandler()->SameValue(handler));
 
   proxy->Revoke();
   CHECK(proxy->IsProxy());
   CHECK(!target->IsProxy());
   CHECK(proxy->IsRevoked());
   CHECK(proxy->GetTarget()->SameValue(target));
   CHECK(proxy->GetHandler()->IsNull());
 }