node, async-wrap: remove MakeDomainCallback

C++ won't deoptimize like JS if specific conditional branches are
sporadically met in the future. Combined with the amount of code
duplication removal and simplified maintenance complexity, it makes more
sense to merge MakeCallback and MakeDomainCallback.

Additionally, type casting in V8 before verifying what that type is will
cause V8 to abort in debug mode if that type isn't what was expected.
Fix this by first checking the v8::Value before casting.

PR-URL: https://github.com/joyent/node/pull/8110
Signed-off-by: Trevor Norris <trev.norris@gmail.com>
Reviewed-by: Fedor Indutny <fedor@indutny.com>
Reviewed-by: Alexis Campailla <alexis@janeasystems.com>
Reviewed-by: Julien Gilli <julien.gilli@joyent.com>

src/async-wrap-inl.h

@@ -51,10 +51,8 @@ inline v8::Handle<v8::Value> AsyncWrap::MakeCallback(
     int argc,
     v8::Handle<v8::Value>* argv) {
   v8::Local<v8::Value> cb_v = object()->Get(symbol);
-  v8::Local<v8::Function> cb = cb_v.As<v8::Function>();
-  CHECK(cb->IsFunction());
-
-  return MakeCallback(cb, argc, argv);
+  CHECK(cb_v->IsFunction());
+  return MakeCallback(cb_v.As<v8::Function>(), argc, argv);
 }
 
 
@@ -63,10 +61,8 @@ inline v8::Handle<v8::Value> AsyncWrap::MakeCallback(
     int argc,
     v8::Handle<v8::Value>* argv) {
   v8::Local<v8::Value> cb_v = object()->Get(index);
-  v8::Local<v8::Function> cb = cb_v.As<v8::Function>();
-  CHECK(cb->IsFunction());
-
-  return MakeCallback(cb, argc, argv);
+  CHECK(cb_v->IsFunction());
+  return MakeCallback(cb_v.As<v8::Function>(), argc, argv);
 }
 
 }  // namespace node

src/async-wrap.cc

@@ -37,101 +37,53 @@ using v8::Value;
 
 namespace node {
 
-Handle<Value> AsyncWrap::MakeDomainCallback(const Handle<Function> cb,
-                                            int argc,
-                                            Handle<Value>* argv) {
-  CHECK(env()->context() == env()->isolate()->GetCurrentContext());
-
-  Local<Object> context = object();
-  Local<Object> process = env()->process_object();
-  Local<Value> domain_v = context->Get(env()->domain_string());
-  Local<Object> domain;
-
-  TryCatch try_catch;
-  try_catch.SetVerbose(true);
-
-  bool has_domain = domain_v->IsObject();
-  if (has_domain) {
-    domain = domain_v.As<Object>();
-
-    if (domain->Get(env()->disposed_string())->IsTrue())
-      return Undefined(env()->isolate());
-
-    Local<Function> enter =
-      domain->Get(env()->enter_string()).As<Function>();
-    if (enter->IsFunction()) {
-      enter->Call(domain, 0, nullptr);
-      if (try_catch.HasCaught())
-        return Undefined(env()->isolate());
-    }
-  }
-
-  Local<Value> ret = cb->Call(context, argc, argv);
-
-  if (try_catch.HasCaught()) {
-    return Undefined(env()->isolate());
-  }
-
-  if (has_domain) {
-    Local<Function> exit =
-      domain->Get(env()->exit_string()).As<Function>();
-    if (exit->IsFunction()) {
-      exit->Call(domain, 0, nullptr);
-      if (try_catch.HasCaught())
-        return Undefined(env()->isolate());
-    }
-  }
-
-  Environment::TickInfo* tick_info = env()->tick_info();
-
-  if (tick_info->in_tick()) {
-    return ret;
-  }
-
-  if (tick_info->length() == 0) {
-    env()->isolate()->RunMicrotasks();
-  }
-
-  if (tick_info->length() == 0) {
-    tick_info->set_index(0);
-    return ret;
-  }
-
-  tick_info->set_in_tick(true);
-
-  env()->tick_callback_function()->Call(process, 0, nullptr);
-
-  tick_info->set_in_tick(false);
-
-  if (try_catch.HasCaught()) {
-    tick_info->set_last_threw(true);
-    return Undefined(env()->isolate());
-  }
-
-  return ret;
-}
-
-
 Handle<Value> AsyncWrap::MakeCallback(const Handle<Function> cb,
                                       int argc,
                                       Handle<Value>* argv) {
-  if (env()->using_domains())
-    return MakeDomainCallback(cb, argc, argv);
-
   CHECK(env()->context() == env()->isolate()->GetCurrentContext());
 
   Local<Object> context = object();
   Local<Object> process = env()->process_object();
+  Local<Object> domain;
+  bool has_domain = false;
+
+  if (env()->using_domains()) {
+    Local<Value> domain_v = context->Get(env()->domain_string());
+    has_domain = domain_v->IsObject();
+    if (has_domain) {
+      domain = domain_v.As<Object>();
+      if (domain->Get(env()->disposed_string())->IsTrue())
+        return Undefined(env()->isolate());
+    }
+  }
 
   TryCatch try_catch;
   try_catch.SetVerbose(true);
 
+  if (has_domain) {
+    Local<Value> enter_v = domain->Get(env()->enter_string());
+    if (enter_v->IsFunction()) {
+      enter_v.As<Function>()->Call(domain, 0, nullptr);
+      if (try_catch.HasCaught())
+        return Undefined(env()->isolate());
+    }
+  }
+
   Local<Value> ret = cb->Call(context, argc, argv);
 
   if (try_catch.HasCaught()) {
     return Undefined(env()->isolate());
   }
 
+  if (has_domain) {
+    Local<Value> exit_v = domain->Get(env()->exit_string());
+    if (exit_v->IsFunction()) {
+      exit_v.As<Function>()->Call(domain, 0, nullptr);
+      if (try_catch.HasCaught())
+        return Undefined(env()->isolate());
+    }
+  }
+
   Environment::TickInfo* tick_info = env()->tick_info();
 
   if (tick_info->in_tick()) {

src/async-wrap.h

@@ -74,13 +74,6 @@ class AsyncWrap : public BaseObject {
  private:
   inline AsyncWrap();
 
-  // TODO(trevnorris): BURN IN FIRE! Remove this as soon as a suitable
-  // replacement is committed.
-  v8::Handle<v8::Value> MakeDomainCallback(
-      const v8::Handle<v8::Function> cb,
-      int argc,
-      v8::Handle<v8::Value>* argv);
-
   uint32_t provider_type_;
 };
 

src/node.cc

@@ -986,111 +986,55 @@ void SetupNextTick(const FunctionCallbackInfo<Value>& args) {
 }
 
 
-Handle<Value> MakeDomainCallback(Environment* env,
-                                 Handle<Value> recv,
-                                 const Handle<Function> callback,
-                                 int argc,
-                                 Handle<Value> argv[]) {
-  // If you hit this assertion, you forgot to enter the v8::Context first.
-  CHECK_EQ(env->context(), env->isolate()->GetCurrentContext());
-
-  Local<Object> process = env->process_object();
-  Local<Object> object, domain;
-  Local<Value> domain_v;
-
-  TryCatch try_catch;
-  try_catch.SetVerbose(true);
-
-  bool has_domain = false;
-
-  if (!object.IsEmpty()) {
-    domain_v = object->Get(env->domain_string());
-    has_domain = domain_v->IsObject();
-    if (has_domain) {
-      domain = domain_v.As<Object>();
-
-      if (domain->Get(env->disposed_string())->IsTrue()) {
-        // domain has been disposed of.
-        return Undefined(env->isolate());
-      }
-
-      Local<Function> enter = domain->Get(env->enter_string()).As<Function>();
-      if (enter->IsFunction()) {
-        enter->Call(domain, 0, nullptr);
-        if (try_catch.HasCaught())
-          return Undefined(env->isolate());
-      }
-    }
-  }
-
-  Local<Value> ret = callback->Call(recv, argc, argv);
-
-  if (try_catch.HasCaught()) {
-    return Undefined(env->isolate());
-  }
-
-  if (has_domain) {
-    Local<Function> exit = domain->Get(env->exit_string()).As<Function>();
-    if (exit->IsFunction()) {
-      exit->Call(domain, 0, nullptr);
-      if (try_catch.HasCaught())
-        return Undefined(env->isolate());
-    }
-  }
-
-  Environment::TickInfo* tick_info = env->tick_info();
-
-  if (tick_info->last_threw() == 1) {
-    tick_info->set_last_threw(0);
-    return ret;
-  }
-
-  if (tick_info->in_tick()) {
-    return ret;
-  }
-
-  if (tick_info->length() == 0) {
-    env->isolate()->RunMicrotasks();
-  }
-
-  if (tick_info->length() == 0) {
-    tick_info->set_index(0);
-    return ret;
-  }
-
-  tick_info->set_in_tick(true);
-
-  env->tick_callback_function()->Call(process, 0, nullptr);
-
-  tick_info->set_in_tick(false);
-
-  if (try_catch.HasCaught()) {
-    tick_info->set_last_threw(true);
-    return Undefined(env->isolate());
-  }
-
-  return ret;
-}
-
-
 Handle<Value> MakeCallback(Environment* env,
                            Handle<Value> recv,
                            const Handle<Function> callback,
                            int argc,
                            Handle<Value> argv[]) {
-  if (env->using_domains())
-    return MakeDomainCallback(env, recv, callback, argc, argv);
-
   // If you hit this assertion, you forgot to enter the v8::Context first.
   CHECK_EQ(env->context(), env->isolate()->GetCurrentContext());
 
   Local<Object> process = env->process_object();
+  Local<Object> object, domain;
+  bool has_domain = false;
+
+  if (env->using_domains()) {
+    CHECK(recv->IsObject());
+    object = recv.As<Object>();
+    Local<Value> domain_v = object->Get(env->domain_string());
+    has_domain = domain_v->IsObject();
+    if (has_domain) {
+      domain = domain_v.As<Object>();
+      if (domain->Get(env->disposed_string())->IsTrue())
+        return Undefined(env->isolate());
+    }
+  }
 
   TryCatch try_catch;
   try_catch.SetVerbose(true);
 
+  if (has_domain) {
+    Local<Value> enter_v = domain->Get(env->enter_string());
+    if (enter_v->IsFunction()) {
+        enter_v.As<Function>()->Call(domain, 0, nullptr);
+      if (try_catch.HasCaught())
+        return Undefined(env->isolate());
+    }
+  }
+
   Local<Value> ret = callback->Call(recv, argc, argv);
 
+  if (has_domain) {
+    Local<Value> exit_v = domain->Get(env->exit_string());
+    if (exit_v->IsFunction()) {
+      exit_v.As<Function>()->Call(domain, 0, nullptr);
+      if (try_catch.HasCaught())
+        return Undefined(env->isolate());
+    }
+  }
+  env->tick_callback_function()->Call(process, 0, nullptr);
+  CHECK_EQ(env->context(), env->isolate()->GetCurrentContext());
+
   if (try_catch.HasCaught()) {
     return Undefined(env->isolate());
   }
@@ -1132,10 +1076,9 @@ Handle<Value> MakeCallback(Environment* env,
                            uint32_t index,
                            int argc,
                            Handle<Value> argv[]) {
-  Local<Function> callback = recv->Get(index).As<Function>();
-  CHECK(callback->IsFunction());
-
-  return MakeCallback(env, recv.As<Value>(), callback, argc, argv);
+  Local<Value> cb_v = recv->Get(index);
+  CHECK(cb_v->IsFunction());
+  return MakeCallback(env, recv.As<Value>(), cb_v.As<Function>(), argc, argv);
 }
 
 
@@ -1144,9 +1087,9 @@ Handle<Value> MakeCallback(Environment* env,
                            Handle<String> symbol,
                            int argc,
                            Handle<Value> argv[]) {
-  Local<Function> callback = recv->Get(symbol).As<Function>();
-  CHECK(callback->IsFunction());
-  return MakeCallback(env, recv.As<Value>(), callback, argc, argv);
+  Local<Value> cb_v = recv->Get(symbol);
+  CHECK(cb_v->IsFunction());
+  return MakeCallback(env, recv.As<Value>(), cb_v.As<Function>(), argc, argv);
 }
 
 
@@ -1203,20 +1146,6 @@ Handle<Value> MakeCallback(Isolate* isolate,
 }
 
 
-Handle<Value> MakeDomainCallback(Handle<Object> recv,
-                                 Handle<Function> callback,
-                                 int argc,
-                                 Handle<Value> argv[]) {
-  Local<Context> context = recv->CreationContext();
-  Environment* env = Environment::GetCurrent(context);
-  Context::Scope context_scope(context);
-  EscapableHandleScope handle_scope(env->isolate());
-  return handle_scope.Escape(Local<Value>::New(
-      env->isolate(),
-      MakeDomainCallback(env, recv, callback, argc, argv)));
-}
-
-
 enum encoding ParseEncoding(Isolate* isolate,
                             Handle<Value> encoding_v,
                             enum encoding _default) {