Remove duplicate C++ implementation of Object.prototype.toString

The only caller was the API, and it can just as easily use the
TurboFan version.

R=franzih@chromium.org

Review-Url: https://codereview.chromium.org/2603493002
Cr-Commit-Position: refs/heads/master@{#41962}

src/api.cc

@@ -4475,12 +4475,14 @@ MaybeLocal<Array> v8::Object::GetOwnPropertyNames(Local<Context> context,
 
 MaybeLocal<String> v8::Object::ObjectProtoToString(Local<Context> context) {
   PREPARE_FOR_EXECUTION(context, Object, ObjectProtoToString, String);
-  auto obj = Utils::OpenHandle(this);
+  auto self = Utils::OpenHandle(this);
-  Local<String> result;
+  Local<Value> result;
   has_pending_exception =
-      !ToLocal<String>(i::JSObject::ObjectProtoToString(isolate, obj), &result);
+      !ToLocal<Value>(i::Execution::Call(isolate, isolate->object_to_string(),
+                                         self, 0, nullptr),
+                      &result);
   RETURN_ON_FAILED_EXECUTION(String);
-  RETURN_ESCAPED(result);
+  RETURN_ESCAPED(Local<String>::Cast(result));
 }
 
 

src/objects.cc

@@ -16290,94 +16290,6 @@ bool JSObject::WasConstructedFromApiFunction() {
   return is_api_object;
 }
 
-MaybeHandle<String> Object::ObjectProtoToString(Isolate* isolate,
-                                                Handle<Object> object) {
-  if (*object == isolate->heap()->undefined_value()) {
-    return isolate->factory()->undefined_to_string();
-  }
-  if (*object == isolate->heap()->null_value()) {
-    return isolate->factory()->null_to_string();
-  }
-
-  Handle<JSReceiver> receiver =
-      Object::ToObject(isolate, object).ToHandleChecked();
-
-  // For proxies, we must check IsArray() before get(toStringTag) to comply
-  // with the specification
-  Maybe<bool> is_array = Nothing<bool>();
-  InstanceType instance_type = receiver->map()->instance_type();
-  if (instance_type == JS_PROXY_TYPE) {
-    is_array = Object::IsArray(receiver);
-    MAYBE_RETURN(is_array, MaybeHandle<String>());
-  }
-
-  Handle<String> tag;
-  Handle<Object> to_string_tag;
-  ASSIGN_RETURN_ON_EXCEPTION(
-      isolate, to_string_tag,
-      JSReceiver::GetProperty(receiver,
-                              isolate->factory()->to_string_tag_symbol()),
-      String);
-  if (to_string_tag->IsString()) {
-    tag = Handle<String>::cast(to_string_tag);
-  } else {
-    switch (instance_type) {
-      case JS_API_OBJECT_TYPE:
-      case JS_SPECIAL_API_OBJECT_TYPE:
-        tag = handle(receiver->class_name(), isolate);
-        break;
-      case JS_ARGUMENTS_TYPE:
-        return isolate->factory()->arguments_to_string();
-      case JS_ARRAY_TYPE:
-        return isolate->factory()->array_to_string();
-      case JS_BOUND_FUNCTION_TYPE:
-      case JS_FUNCTION_TYPE:
-        return isolate->factory()->function_to_string();
-      case JS_ERROR_TYPE:
-        return isolate->factory()->error_to_string();
-      case JS_DATE_TYPE:
-        return isolate->factory()->date_to_string();
-      case JS_REGEXP_TYPE:
-        return isolate->factory()->regexp_to_string();
-      case JS_PROXY_TYPE: {
-        if (is_array.FromJust()) {
-          return isolate->factory()->array_to_string();
-        }
-        if (receiver->IsCallable()) {
-          return isolate->factory()->function_to_string();
-        }
-        return isolate->factory()->object_to_string();
-      }
-      case JS_VALUE_TYPE: {
-        Object* value = JSValue::cast(*receiver)->value();
-        if (value->IsString()) {
-          return isolate->factory()->string_to_string();
-        }
-        if (value->IsNumber()) {
-          return isolate->factory()->number_to_string();
-        }
-        if (value->IsBoolean()) {
-          return isolate->factory()->boolean_to_string();
-        }
-        if (value->IsSymbol()) {
-          return isolate->factory()->object_to_string();
-        }
-        UNREACHABLE();
-        tag = handle(receiver->class_name(), isolate);
-        break;
-      }
-      default:
-        return isolate->factory()->object_to_string();
-    }
-  }
-
-  IncrementalStringBuilder builder(isolate);
-  builder.AppendCString("[object ");
-  builder.AppendString(tag);
-  builder.AppendCharacter(']');
-  return builder.Finish();
-}
-
 const char* Symbol::PrivateSymbolToName() const {
   Heap* heap = GetIsolate()->heap();
 #define SYMBOL_CHECK_AND_PRINT(name) \

src/objects.h

@@ -1496,10 +1496,6 @@ class Object {
 
   inline void VerifyApiCallResultType();
 
-  // ES6 19.1.3.6 Object.prototype.toString
-  MUST_USE_RESULT static MaybeHandle<String> ObjectProtoToString(
-      Isolate* isolate, Handle<Object> object);
-
   // Prints this object without details.
   void ShortPrint(FILE* out = stdout);