Introduce MicrotasksCompletedCallback.

test/cctest/test-api.cc

Index: test/cctest/test-api.cc
diff --git a/test/cctest/test-api.cc b/test/cctest/test-api.cc
index f4e8fe8e4bd36b6f4f934c962ce4f28a4100ffca..e9b2fce7f051ace5ded179f59d73dbdebb73bc60 100644
--- a/test/cctest/test-api.cc
+++ b/test/cctest/test-api.cc
@@ -21033,21 +21033,33 @@ TEST(RunMicrotasksIgnoresThrownExceptions) {
 }
 
 
+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(
@@ -21057,20 +21069,24 @@ TEST(SetAutorunMicrotasks) {
   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(
@@ -21078,6 +21094,7 @@ TEST(SetAutorunMicrotasks) {
   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());
@@ -21086,11 +21103,22 @@ TEST(SetAutorunMicrotasks) {
     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);
 }