[intl] Refactor instance type checks

Adds Intl::IsObjectOfType method to do type checks. This will make it
easier to port the methods using the runtime type check calls as we
won't have to create a v8::string for type checks.

Bug: v8:5751
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I0babdc8709564be693ce808e2ef3ffef7b24ceec
Reviewed-on: https://chromium-review.googlesource.com/1121943
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54143}

BUILD.gn

@@ -2122,6 +2122,7 @@ v8_source_set("v8_base") {
     "src/objects/frame-array.h",
     "src/objects/hash-table-inl.h",
     "src/objects/hash-table.h",
+    "src/objects/intl-objects-inl.h",
     "src/objects/intl-objects.cc",
     "src/objects/intl-objects.h",
     "src/objects/js-array-inl.h",
@@ -2804,6 +2805,7 @@ v8_source_set("v8_base") {
       "src/char-predicates.cc",
       "src/intl.cc",
       "src/intl.h",
+      "src/objects/intl-objects-inl.h",
       "src/objects/intl-objects.cc",
       "src/objects/intl-objects.h",
       "src/objects/js-locale-inl.h",

src/builtins/builtins-intl.cc

@@ -443,12 +443,8 @@ BUILTIN(NumberFormatPrototypeFormatToParts) {
   HandleScope handle_scope(isolate);
   CHECK_RECEIVER(JSObject, number_format_holder, method);
 
-  Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
-  Handle<Object> tag =
-      JSReceiver::GetDataProperty(number_format_holder, marker);
-  Handle<String> expected_tag =
-      isolate->factory()->NewStringFromStaticChars("numberformat");
-  if (!(tag->IsString() && String::cast(*tag)->Equals(*expected_tag))) {
+  if (!Intl::IsObjectOfType(isolate, number_format_holder,
+                            Intl::Type::kNumberFormat)) {
     THROW_NEW_ERROR_RETURN_FAILURE(
         isolate,
         NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
@@ -478,10 +474,8 @@ BUILTIN(DateTimeFormatPrototypeFormatToParts) {
   CHECK_RECEIVER(JSObject, date_format_holder, method);
   Factory* factory = isolate->factory();
 
-  Handle<Symbol> marker = factory->intl_initialized_marker_symbol();
-  Handle<Object> tag = JSReceiver::GetDataProperty(date_format_holder, marker);
-  Handle<String> expected_tag = factory->NewStringFromStaticChars("dateformat");
-  if (!(tag->IsString() && String::cast(*tag)->Equals(*expected_tag))) {
+  if (!Intl::IsObjectOfType(isolate, date_format_holder,
+                            Intl::Type::kDateTimeFormat)) {
     THROW_NEW_ERROR_RETURN_FAILURE(
         isolate, NewTypeError(MessageTemplate::kIncompatibleMethodReceiver,
                               factory->NewStringFromAsciiChecked(method),

src/js/intl.js

@@ -67,7 +67,7 @@ endmacro
 /**
  * Adds bound method to the prototype of the given object.
  */
-function AddBoundMethod(obj, methodName, implementation, length, typename,
+function AddBoundMethod(obj, methodName, implementation, length, type,
                         compat) {
   %CheckIsBootstrapping();
   var internalName = %CreatePrivateSymbol(methodName);
@@ -75,7 +75,7 @@ function AddBoundMethod(obj, methodName, implementation, length, typename,
   DEFINE_METHOD(
     obj.prototype,
     get [methodName]() {
-      var receiver = Unwrap(this, typename, obj, methodName, compat);
+      var receiver = Unwrap(this, type, obj, methodName, compat);
       if (IS_UNDEFINED(receiver[internalName])) {
         var boundMethod;
         if (IS_UNDEFINED(length) || length === 2) {
@@ -120,11 +120,11 @@ function IntlConstruct(receiver, constructor, create, newTarget, args,
 
 
 
-function Unwrap(receiver, typename, constructor, method, compat) {
-  if (!%IsInitializedIntlObjectOfType(receiver, typename)) {
+function Unwrap(receiver, type, constructor, method, compat) {
+  if (!%IsInitializedIntlObjectOfType(receiver, type)) {
     if (compat && receiver instanceof constructor) {
       let fallback = receiver[IntlFallbackSymbol];
-      if (%IsInitializedIntlObjectOfType(fallback, typename)) {
+      if (%IsInitializedIntlObjectOfType(fallback, type)) {
         return fallback;
       }
     }
@@ -1053,7 +1053,7 @@ function CreateCollator(locales, options) {
 
   var collator = %CreateCollator(requestedLocale, internalOptions, resolved);
 
-  %MarkAsInitializedIntlObjectOfType(collator, 'collator');
+  %MarkAsInitializedIntlObjectOfType(collator, COLLATOR_TYPE);
   collator[resolvedSymbol] = resolved;
 
   return collator;
@@ -1079,8 +1079,8 @@ function CollatorConstructor() {
 DEFINE_METHOD(
   GlobalIntlCollator.prototype,
   resolvedOptions() {
-    var coll = Unwrap(this, 'collator', GlobalIntlCollator, 'resolvedOptions',
-                      false);
+    var coll = Unwrap(this, COLLATOR_TYPE, GlobalIntlCollator,
+                      'resolvedOptions', false);
     return {
       locale: coll[resolvedSymbol].locale,
       usage: coll[resolvedSymbol].usage,
@@ -1123,7 +1123,7 @@ function compare(collator, x, y) {
 };
 
 
-AddBoundMethod(GlobalIntlCollator, 'compare', compare, 2, 'collator', false);
+AddBoundMethod(GlobalIntlCollator, 'compare', compare, 2, COLLATOR_TYPE, false);
 
 function PluralRulesConstructor() {
   if (IS_UNDEFINED(new.target)) {
@@ -1166,7 +1166,7 @@ function PluralRulesConstructor() {
   var pluralRules = %CreatePluralRules(requestedLocale, internalOptions,
                                        resolved);
 
-  %MarkAsInitializedIntlObjectOfType(pluralRules, 'pluralrules');
+  %MarkAsInitializedIntlObjectOfType(pluralRules, PLURAL_RULES_TYPE);
   pluralRules[resolvedSymbol] = resolved;
 
   return pluralRules;
@@ -1176,7 +1176,7 @@ function PluralRulesConstructor() {
 DEFINE_METHOD(
   GlobalIntlPluralRules.prototype,
   resolvedOptions() {
-    if (!%IsInitializedIntlObjectOfType(this, 'pluralrules')) {
+    if (!%IsInitializedIntlObjectOfType(this, PLURAL_RULES_TYPE)) {
       throw %make_type_error(kIncompatibleMethodReceiver,
                              'Intl.PluralRules.prototype.resolvedOptions',
                              this);
@@ -1217,7 +1217,7 @@ DEFINE_METHOD(
 DEFINE_METHOD(
   GlobalIntlPluralRules.prototype,
   select(value) {
-    if (!%IsInitializedIntlObjectOfType(this, 'pluralrules')) {
+    if (!%IsInitializedIntlObjectOfType(this, PLURAL_RULES_TYPE)) {
       throw %make_type_error(kIncompatibleMethodReceiver,
                             'Intl.PluralRules.prototype.select',
                             this);
@@ -1378,7 +1378,7 @@ function CreateNumberFormat(locales, options) {
         {value: currencyDisplay, writable: true});
   }
 
-  %MarkAsInitializedIntlObjectOfType(numberFormat, 'numberformat');
+  %MarkAsInitializedIntlObjectOfType(numberFormat, NUMBER_FORMAT_TYPE);
   numberFormat[resolvedSymbol] = resolved;
 
   return numberFormat;
@@ -1404,7 +1404,7 @@ function NumberFormatConstructor() {
 DEFINE_METHOD(
   GlobalIntlNumberFormat.prototype,
   resolvedOptions() {
-    var format = Unwrap(this, 'numberformat', GlobalIntlNumberFormat,
+    var format = Unwrap(this, NUMBER_FORMAT_TYPE, GlobalIntlNumberFormat,
                         'resolvedOptions', true);
     var result = {
       locale: format[resolvedSymbol].locale,
@@ -1465,7 +1465,7 @@ function formatNumber(formatter, value) {
 
 
 AddBoundMethod(GlobalIntlNumberFormat, 'format', formatNumber, 1,
-               'numberformat', true);
+               NUMBER_FORMAT_TYPE, true);
 
 /**
  * Returns a string that matches LDML representation of the options object.
@@ -1740,7 +1740,7 @@ function CreateDateTimeFormat(locales, options) {
     throw %make_range_error(kUnsupportedTimeZone, tz);
   }
 
-  %MarkAsInitializedIntlObjectOfType(dateFormat, 'dateformat');
+  %MarkAsInitializedIntlObjectOfType(dateFormat, DATE_TIME_FORMAT_TYPE);
   dateFormat[resolvedSymbol] = resolved;
 
   return dateFormat;
@@ -1766,7 +1766,7 @@ function DateTimeFormatConstructor() {
 DEFINE_METHOD(
   GlobalIntlDateTimeFormat.prototype,
   resolvedOptions() {
-    var format = Unwrap(this, 'dateformat', GlobalIntlDateTimeFormat,
+    var format = Unwrap(this, DATE_TIME_FORMAT_TYPE, GlobalIntlDateTimeFormat,
                         'resolvedOptions', true);
 
     /**
@@ -1841,7 +1841,7 @@ function formatDate(formatter, dateValue) {
 }
 
 // Length is 1 as specified in ECMA 402 v2+
-AddBoundMethod(GlobalIntlDateTimeFormat, 'format', formatDate, 1, 'dateformat',
+AddBoundMethod(GlobalIntlDateTimeFormat, 'format', formatDate, 1, DATE_TIME_FORMAT_TYPE,
                true);
 
 
@@ -1911,7 +1911,7 @@ function CreateBreakIterator(locales, options) {
 
   var iterator = %CreateBreakIterator(locale.locale, internalOptions, resolved);
 
-  %MarkAsInitializedIntlObjectOfType(iterator, 'breakiterator');
+  %MarkAsInitializedIntlObjectOfType(iterator, BREAK_ITERATOR_TYPE);
   iterator[resolvedSymbol] = resolved;
 
   return iterator;
@@ -1941,7 +1941,7 @@ DEFINE_METHOD(
       throw %make_type_error(kOrdinaryFunctionCalledAsConstructor);
     }
 
-    var segmenter = Unwrap(this, 'breakiterator', GlobalIntlv8BreakIterator,
+    var segmenter = Unwrap(this, BREAK_ITERATOR_TYPE, GlobalIntlv8BreakIterator,
                            'resolvedOptions', false);
 
     return {
@@ -2012,13 +2012,15 @@ function breakType(iterator) {
 
 
 AddBoundMethod(GlobalIntlv8BreakIterator, 'adoptText', adoptText, 1,
-               'breakiterator');
-AddBoundMethod(GlobalIntlv8BreakIterator, 'first', first, 0, 'breakiterator');
-AddBoundMethod(GlobalIntlv8BreakIterator, 'next', next, 0, 'breakiterator');
+               BREAK_ITERATOR_TYPE);
+AddBoundMethod(GlobalIntlv8BreakIterator, 'first', first, 0,
+               BREAK_ITERATOR_TYPE);
+AddBoundMethod(GlobalIntlv8BreakIterator, 'next', next, 0,
+               BREAK_ITERATOR_TYPE);
 AddBoundMethod(GlobalIntlv8BreakIterator, 'current', current, 0,
-               'breakiterator');
+               BREAK_ITERATOR_TYPE);
 AddBoundMethod(GlobalIntlv8BreakIterator, 'breakType', breakType, 0,
-               'breakiterator');
+               BREAK_ITERATOR_TYPE);
 
 // Save references to Intl objects and methods we use, for added security.
 var savedObjects = {

src/js/macros.py

@@ -83,3 +83,11 @@ macro DEFINE_METHOD(obj, method_def) = DEFINE_METHOD_LEN(obj, method_def, -1);
 # Constants.  The compiler constant folds them.
 define INFINITY = (1/0);
 define UNDEFINED = (void 0);
+
+# This should be kept consistent with Intl::Type.
+define NUMBER_FORMAT_TYPE = 0;
+define COLLATOR_TYPE = 1;
+define DATE_TIME_FORMAT_TYPE = 2;
+define PLURAL_RULES_TYPE = 3;
+define BREAK_ITERATOR_TYPE = 4;
+define LOCALE_TYPE = 5;

src/objects/intl-objects-inl.h

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_OBJECTS_INTL_OBJECTS_INL_H_
+#define V8_OBJECTS_INTL_OBJECTS_INL_H_
+
+#include "src/objects/intl-objects.h"
+
+namespace v8 {
+namespace internal {
+
+inline Intl::Type Intl::TypeFromInt(int type_int) {
+  STATIC_ASSERT(Intl::Type::kNumberFormat == 0);
+  DCHECK_LE(Intl::Type::kNumberFormat, type_int);
+  DCHECK_GT(Intl::Type::kTypeCount, type_int);
+  return static_cast<Intl::Type>(type_int);
+}
+
+inline Intl::Type Intl::TypeFromSmi(Smi* type) {
+  return TypeFromInt(Smi::ToInt(type));
+}
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_OBJECTS_INTL_OBJECTS_INL_H_

src/objects/intl-objects.cc

@@ -7,6 +7,7 @@
 #endif  // V8_INTL_SUPPORT
 
 #include "src/objects/intl-objects.h"
+#include "src/objects/intl-objects-inl.h"
 
 #include <memory>
 
@@ -1080,8 +1081,8 @@ void V8BreakIterator::DeleteBreakIterator(
 }
 
 // Build the shortened locale; eg, convert xx_Yyyy_ZZ  to xx_ZZ.
-bool IntlUtil::RemoveLocaleScriptTag(const std::string& icu_locale,
-                                     std::string* locale_less_script) {
+bool Intl::RemoveLocaleScriptTag(const std::string& icu_locale,
+                                 std::string* locale_less_script) {
   icu::Locale new_locale = icu::Locale::createCanonical(icu_locale.c_str());
   const char* icu_script = new_locale.getScript();
   if (icu_script == NULL || strlen(icu_script) == 0) {
@@ -1097,7 +1098,7 @@ bool IntlUtil::RemoveLocaleScriptTag(const std::string& icu_locale,
   return true;
 }
 
-std::set<std::string> IntlUtil::GetAvailableLocales(const IcuService& service) {
+std::set<std::string> Intl::GetAvailableLocales(const IcuService& service) {
   const icu::Locale* icu_available_locales = nullptr;
   int32_t count = 0;
 
@@ -1142,7 +1143,7 @@ std::set<std::string> IntlUtil::GetAvailableLocales(const IcuService& service) {
     locales.insert(locale);
 
     std::string shortened_locale;
-    if (IntlUtil::RemoveLocaleScriptTag(icu_name, &shortened_locale)) {
+    if (Intl::RemoveLocaleScriptTag(icu_name, &shortened_locale)) {
       std::replace(shortened_locale.begin(), shortened_locale.end(), '_', '-');
       locales.insert(shortened_locale);
     }
@@ -1151,5 +1152,19 @@ std::set<std::string> IntlUtil::GetAvailableLocales(const IcuService& service) {
   return locales;
 }
 
+bool Intl::IsObjectOfType(Isolate* isolate, Handle<Object> input,
+                          Intl::Type expected_type) {
+  if (!input->IsJSObject()) return false;
+  Handle<JSObject> obj = Handle<JSObject>::cast(input);
+
+  Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
+  Handle<Object> tag = JSReceiver::GetDataProperty(obj, marker);
+
+  if (!tag->IsSmi()) return false;
+
+  Intl::Type type = Intl::TypeFromSmi(Smi::cast(*tag));
+  return type == expected_type;
+}
+
 }  // namespace internal
 }  // namespace v8

src/objects/intl-objects.h

@@ -163,13 +163,36 @@ class V8BreakIterator {
   V8BreakIterator();
 };
 
-class IntlUtil {
+class Intl {
  public:
+  enum Type {
+    kNumberFormat = 0,
+    kCollator,
+    kDateTimeFormat,
+    kPluralRules,
+    kBreakIterator,
+    kLocale,
+
+    kTypeCount
+  };
+
+  inline static Intl::Type TypeFromInt(int type);
+  inline static Intl::Type TypeFromSmi(Smi* type);
+
+  // Checks if the given object has the expected_type based by looking
+  // up a private symbol on the object.
+  //
+  // TODO(gsathya): This should just be an instance type check once we
+  // move all the Intl objects to C++.
+  static bool IsObjectOfType(Isolate* isolate, Handle<Object> object,
+                             Intl::Type expected_type);
+
   // Gets the ICU locales for a given service. If there is a locale with a
   // script tag then the locales also include a locale without the script; eg,
   // pa_Guru_IN (language=Panjabi, script=Gurmukhi, country-India) would include
   // pa_IN.
   static std::set<std::string> GetAvailableLocales(const IcuService& service);
+
   // If locale has a script tag then return true and the locale without the
   // script else return false and an empty string
   static bool RemoveLocaleScriptTag(const std::string& icu_locale,

src/runtime/runtime-intl.cc

@@ -20,6 +20,7 @@
 #include "src/intl.h"
 #include "src/isolate-inl.h"
 #include "src/messages.h"
+#include "src/objects/intl-objects-inl.h"
 #include "src/objects/intl-objects.h"
 #include "src/utils.h"
 
@@ -172,36 +173,18 @@ RUNTIME_FUNCTION(Runtime_GetDefaultICULocale) {
   return *factory->NewStringFromStaticChars("und");
 }
 
-RUNTIME_FUNCTION(Runtime_IsInitializedIntlObject) {
-  HandleScope scope(isolate);
-
-  DCHECK_EQ(1, args.length());
-
-  CONVERT_ARG_HANDLE_CHECKED(Object, input, 0);
-
-  if (!input->IsJSObject()) return isolate->heap()->false_value();
-  Handle<JSObject> obj = Handle<JSObject>::cast(input);
-
-  Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
-  Handle<Object> tag = JSReceiver::GetDataProperty(obj, marker);
-  return isolate->heap()->ToBoolean(!tag->IsUndefined(isolate));
-}
-
 RUNTIME_FUNCTION(Runtime_IsInitializedIntlObjectOfType) {
   HandleScope scope(isolate);
 
   DCHECK_EQ(2, args.length());
 
   CONVERT_ARG_HANDLE_CHECKED(Object, input, 0);
-  CONVERT_ARG_HANDLE_CHECKED(String, expected_type, 1);
+  CONVERT_SMI_ARG_CHECKED(expected_type_int, 1);
 
-  if (!input->IsJSObject()) return isolate->heap()->false_value();
-  Handle<JSObject> obj = Handle<JSObject>::cast(input);
+  Intl::Type expected_type = Intl::TypeFromInt(expected_type_int);
 
-  Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
-  Handle<Object> tag = JSReceiver::GetDataProperty(obj, marker);
-  return isolate->heap()->ToBoolean(tag->IsString() &&
-                                    String::cast(*tag)->Equals(*expected_type));
+  return isolate->heap()->ToBoolean(
+      Intl::IsObjectOfType(isolate, input, expected_type));
 }
 
 RUNTIME_FUNCTION(Runtime_MarkAsInitializedIntlObjectOfType) {
@@ -210,7 +193,13 @@ RUNTIME_FUNCTION(Runtime_MarkAsInitializedIntlObjectOfType) {
   DCHECK_EQ(2, args.length());
 
   CONVERT_ARG_HANDLE_CHECKED(JSObject, input, 0);
-  CONVERT_ARG_HANDLE_CHECKED(String, type, 1);
+  CONVERT_ARG_HANDLE_CHECKED(Smi, type, 1);
+
+#ifdef DEBUG
+  // TypeFromSmi does correctness checks.
+  Intl::Type type_intl = Intl::TypeFromSmi(*type);
+  USE(type_intl);
+#endif
 
   Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
   JSObject::SetProperty(input, marker, type, LanguageMode::kStrict).Assert();

src/runtime/runtime.h

@@ -225,7 +225,6 @@ namespace internal {
   F(InternalCompare, 3, 1)                   \
   F(InternalDateFormat, 2, 1)                \
   F(InternalNumberFormat, 2, 1)              \
-  F(IsInitializedIntlObject, 1, 1)           \
   F(IsInitializedIntlObjectOfType, 2, 1)     \
   F(MarkAsInitializedIntlObjectOfType, 2, 1) \
   F(PluralRulesSelect, 2, 1)                 \

test/cctest/test-intl.cc

@@ -183,15 +183,13 @@ TEST(GetOptions) {
 
 bool ScriptTagWasRemoved(std::string locale, std::string expected) {
   std::string without_script_tag;
-  bool didShorten =
-      IntlUtil::RemoveLocaleScriptTag(locale, &without_script_tag);
+  bool didShorten = Intl::RemoveLocaleScriptTag(locale, &without_script_tag);
   return didShorten && expected == without_script_tag;
 }
 
 bool ScriptTagWasNotRemoved(std::string locale) {
   std::string without_script_tag;
-  bool didShorten =
-      IntlUtil::RemoveLocaleScriptTag(locale, &without_script_tag);
+  bool didShorten = Intl::RemoveLocaleScriptTag(locale, &without_script_tag);
   return !didShorten && without_script_tag.empty();
 }
 
@@ -209,23 +207,61 @@ TEST(RemoveLocaleScriptTag) {
 TEST(GetAvailableLocales) {
   std::set<std::string> locales;
 
-  locales = IntlUtil::GetAvailableLocales(IcuService::kBreakIterator);
+  locales = Intl::GetAvailableLocales(IcuService::kBreakIterator);
   CHECK(locales.count("en-US"));
   CHECK(!locales.count("abcdefg"));
 
-  locales = IntlUtil::GetAvailableLocales(IcuService::kCollator);
+  locales = Intl::GetAvailableLocales(IcuService::kCollator);
   CHECK(locales.count("en-US"));
 
-  locales = IntlUtil::GetAvailableLocales(IcuService::kDateFormat);
+  locales = Intl::GetAvailableLocales(IcuService::kDateFormat);
   CHECK(locales.count("en-US"));
 
-  locales = IntlUtil::GetAvailableLocales(IcuService::kNumberFormat);
+  locales = Intl::GetAvailableLocales(IcuService::kNumberFormat);
   CHECK(locales.count("en-US"));
 
-  locales = IntlUtil::GetAvailableLocales(IcuService::kPluralRules);
+  locales = Intl::GetAvailableLocales(IcuService::kPluralRules);
   CHECK(locales.count("en-US"));
 }
 
+TEST(IsObjectOfType) {
+  LocalContext env;
+  Isolate* isolate = CcTest::i_isolate();
+  v8::Isolate* v8_isolate = env->GetIsolate();
+  v8::HandleScope handle_scope(v8_isolate);
+
+  Handle<JSObject> obj = isolate->factory()->NewJSObjectWithNullProto();
+  Handle<Symbol> marker = isolate->factory()->intl_initialized_marker_symbol();
+
+  STATIC_ASSERT(Intl::Type::kNumberFormat == 0);
+  Intl::Type types[] = {Intl::Type::kNumberFormat,   Intl::Type::kCollator,
+                        Intl::Type::kDateTimeFormat, Intl::Type::kPluralRules,
+                        Intl::Type::kBreakIterator,  Intl::Type::kLocale};
+
+  for (auto type : types) {
+    Handle<Smi> tag =
+        Handle<Smi>(Smi::FromInt(static_cast<int>(type)), isolate);
+    JSObject::SetProperty(obj, marker, tag, LanguageMode::kStrict).Assert();
+
+    CHECK(Intl::IsObjectOfType(isolate, obj, type));
+  }
+
+  Handle<Object> tag = isolate->factory()->NewStringFromAsciiChecked("foo");
+  JSObject::SetProperty(obj, marker, tag, LanguageMode::kStrict).Assert();
+  CHECK(!Intl::IsObjectOfType(isolate, obj, types[0]));
+
+  CHECK(!Intl::IsObjectOfType(isolate, tag, types[0]));
+  CHECK(!Intl::IsObjectOfType(isolate, Handle<Smi>(Smi::FromInt(0), isolate),
+                              types[0]));
+
+  // Proxy with target as an initialized object should fail.
+  tag = Handle<Smi>(Smi::FromInt(static_cast<int>(types[0])), isolate);
+  JSObject::SetProperty(obj, marker, tag, LanguageMode::kStrict).Assert();
+  Handle<JSReceiver> proxy = isolate->factory()->NewJSProxy(
+      obj, isolate->factory()->NewJSObjectWithNullProto());
+  CHECK(!Intl::IsObjectOfType(isolate, proxy, types[0]));
+}
+
 }  // namespace internal
 }  // namespace v8