[ShadowRealm] Part 1 - Skeleton

1. Expose all the functions to empty builtins.
2. Wire up the basic structure of ShadowRealm and internal slots.

Bug: v8:11989
Change-Id: If7545fe18a74b2bd4b70a1a25776e41f03aaff89
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3195532Reviewed-by: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Chengzhong Wu <legendecas@gmail.com>
Cr-Commit-Position: refs/heads/main@{#78757}

BUILD.bazel

@@ -857,6 +857,7 @@ filegroup(
         "src/objects/js-proxy.tq",
         "src/objects/js-regexp-string-iterator.tq",
         "src/objects/js-regexp.tq",
+        "src/objects/js-shadow-realms.tq",
         "src/objects/js-temporal-objects.tq",
         "src/objects/js-weak-refs.tq",
         "src/objects/literal-objects.tq",
@@ -1051,6 +1052,7 @@ filegroup(
         "src/builtins/builtins-promise.h",
         "src/builtins/builtins-reflect.cc",
         "src/builtins/builtins-regexp.cc",
+        "src/builtins/builtins-shadow-realms.cc",
         "src/builtins/builtins-sharedarraybuffer.cc",
         "src/builtins/builtins-string.cc",
         "src/builtins/builtins-symbol.cc",
@@ -1638,6 +1640,8 @@ filegroup(
         "src/objects/js-regexp-string-iterator.h",
         "src/objects/js-regexp.cc",
         "src/objects/js-regexp.h",
+        "src/objects/js-shadow-realms.h",
+        "src/objects/js-shadow-realms-inl.h",
         "src/objects/js-temporal-objects.h",
         "src/objects/js-temporal-objects-inl.h",
         "src/objects/js-temporal-objects.cc",

BUILD.gn

@@ -1759,6 +1759,7 @@ torque_files = [
   "src/objects/js-proxy.tq",
   "src/objects/js-regexp-string-iterator.tq",
   "src/objects/js-regexp.tq",
+  "src/objects/js-shadow-realms.tq",
   "src/objects/js-temporal-objects.tq",
   "src/objects/js-weak-refs.tq",
   "src/objects/literal-objects.tq",
@@ -3162,6 +3163,8 @@ v8_header_set("v8_internal_headers") {
     "src/objects/js-regexp.h",
     "src/objects/js-segments-inl.h",
     "src/objects/js-segments.h",
+    "src/objects/js-shadow-realms-inl.h",
+    "src/objects/js-shadow-realms.h",
     "src/objects/js-temporal-objects-inl.h",
     "src/objects/js-temporal-objects.h",
     "src/objects/js-weak-refs-inl.h",
@@ -4029,6 +4032,7 @@ v8_source_set("v8_base_without_compiler") {
     "src/builtins/builtins-object.cc",
     "src/builtins/builtins-reflect.cc",
     "src/builtins/builtins-regexp.cc",
+    "src/builtins/builtins-shadow-realms.cc",
     "src/builtins/builtins-sharedarraybuffer.cc",
     "src/builtins/builtins-string.cc",
     "src/builtins/builtins-symbol.cc",

include/v8-callbacks.h

@@ -367,6 +367,20 @@ using HostInitializeImportMetaObjectCallback = void (*)(Local<Context> context,
                                                         Local<Module> module,
                                                         Local<Object> meta);
 
+/**
+ * HostCreateShadowRealmContextCallback is called each time a ShadowRealm is
+ * being constructed in the initiator_context.
+ *
+ * The method combines Context creation and implementation defined abstract
+ * operation HostInitializeShadowRealm into one.
+ *
+ * The embedder should use v8::Context::New or v8::Context:NewFromSnapshot to
+ * create a new context. If the creation fails, the embedder must propagate
+ * that exception by returning an empty MaybeLocal.
+ */
+using HostCreateShadowRealmContextCallback =
+    MaybeLocal<Context> (*)(Local<Context> initiator_context);
+
 /**
  * PrepareStackTraceCallback is called when the stack property of an error is
  * first accessed. The return value will be used as the stack value. If this

include/v8-isolate.h

@@ -641,6 +641,13 @@ class V8_EXPORT Isolate {
   void SetHostInitializeImportMetaObjectCallback(
       HostInitializeImportMetaObjectCallback callback);
 
+  /**
+   * This specifies the callback called by the upcoming ShadowRealm
+   * construction language feature to retrieve host created globals.
+   */
+  void SetHostCreateShadowRealmContextCallback(
+      HostCreateShadowRealmContextCallback callback);
+
   /**
    * This specifies the callback called when the stack property of Error
    * is accessed.

src/api/api.cc

@@ -8816,6 +8816,12 @@ void Isolate::SetHostInitializeImportMetaObjectCallback(
   isolate->SetHostInitializeImportMetaObjectCallback(callback);
 }
 
+void Isolate::SetHostCreateShadowRealmContextCallback(
+    HostCreateShadowRealmContextCallback callback) {
+  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
+  isolate->SetHostCreateShadowRealmContextCallback(callback);
+}
+
 void Isolate::SetPrepareStackTraceCallback(PrepareStackTraceCallback callback) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   isolate->SetPrepareStackTraceCallback(callback);

src/builtins/base.tq

@@ -16,6 +16,7 @@
 #include 'src/objects/js-generator.h'
 #include 'src/objects/js-promise.h'
 #include 'src/objects/js-regexp-string-iterator.h'
+#include 'src/objects/js-shadow-realms.h'
 #include 'src/objects/js-weak-refs.h'
 #include 'src/objects/objects.h'
 #include 'src/objects/source-text-module.h'

src/builtins/builtins-definitions.h

@@ -867,6 +867,11 @@ namespace internal {
   TFJ(SetIteratorPrototypeNext, kJSArgcReceiverSlots, kReceiver)               \
   TFS(SetOrSetIteratorToList, kSource)                                         \
                                                                                \
+  /* ShadowRealm */                                                            \
+  CPP(ShadowRealmConstructor)                                                  \
+  CPP(ShadowRealmPrototypeEvaluate)                                            \
+  CPP(ShadowRealmPrototypeImportValue)                                         \
+                                                                               \
   /* SharedArrayBuffer */                                                      \
   CPP(SharedArrayBufferPrototypeGetByteLength)                                 \
   CPP(SharedArrayBufferPrototypeSlice)                                         \

src/builtins/builtins-shadow-realms.cc

+// Copyright 2021 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.
+
+#include "src/builtins/builtins-utils-inl.h"
+#include "src/logging/counters.h"
+#include "src/objects/js-shadow-realms-inl.h"
+
+namespace v8 {
+namespace internal {
+
+// https://tc39.es/proposal-shadowrealm/#sec-shadowrealm-constructor
+BUILTIN(ShadowRealmConstructor) {
+  HandleScope scope(isolate);
+  // 1. If NewTarget is undefined, throw a TypeError exception.
+  if (args.new_target()->IsUndefined(isolate)) {  // [[Call]]
+    THROW_NEW_ERROR_RETURN_FAILURE(
+        isolate, NewTypeError(MessageTemplate::kConstructorNotFunction,
+                              isolate->factory()->ShadowRealm_string()));
+  }
+  // [[Construct]]
+  Handle<JSFunction> target = args.target();
+  Handle<JSReceiver> new_target = Handle<JSReceiver>::cast(args.new_target());
+
+  // 3. Let realmRec be CreateRealm().
+  // 5. Let context be a new execution context.
+  // 6. Set the Function of context to null.
+  // 7. Set the Realm of context to realmRec.
+  // 8. Set the ScriptOrModule of context to null.
+  // 10. Perform ? SetRealmGlobalObject(realmRec, undefined, undefined).
+  // 11. Perform ? SetDefaultGlobalBindings(O.[[ShadowRealm]]).
+  // 12. Perform ? HostInitializeShadowRealm(O.[[ShadowRealm]]).
+  // These steps are combined in
+  // Isolate::RunHostCreateShadowRealmContextCallback and Context::New.
+  // The host operation is hoisted for not creating a half-initialized
+  // ShadowRealm object, which can fail the heap verification.
+  Handle<NativeContext> native_context;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, native_context,
+      isolate->RunHostCreateShadowRealmContextCallback());
+
+  // 2. Let O be ? OrdinaryCreateFromConstructor(NewTarget,
+  // "%ShadowRealm.prototype%", « [[ShadowRealm]], [[ExecutionContext]] »).
+  Handle<JSObject> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      JSObject::New(target, new_target, Handle<AllocationSite>::null()));
+  Handle<JSShadowRealm> O = Handle<JSShadowRealm>::cast(result);
+
+  // 4. Set O.[[ShadowRealm]] to realmRec.
+  // 9. Set O.[[ExecutionContext]] to context.
+  O->set_native_context(*native_context);
+
+  // 13. Return O.
+  return *O;
+}
+
+// https://tc39.es/proposal-shadowrealm/#sec-shadowrealm.prototype.evaluate
+BUILTIN(ShadowRealmPrototypeEvaluate) {
+  HandleScope scope(isolate);
+  return ReadOnlyRoots(isolate).undefined_value();
+}
+
+// https://tc39.es/proposal-shadowrealm/#sec-shadowrealm.prototype.importvalue
+BUILTIN(ShadowRealmPrototypeImportValue) {
+  HandleScope scope(isolate);
+  return ReadOnlyRoots(isolate).undefined_value();
+}
+
+}  // namespace internal
+}  // namespace v8

src/compiler/types.cc

@@ -257,6 +257,7 @@ Type::bitset BitsetType::Lub(const MapRefLike& map) {
     case JS_WEAK_REF_TYPE:
     case JS_WEAK_SET_TYPE:
     case JS_PROMISE_TYPE:
+    case JS_SHADOW_REALM_TYPE:
     case JS_TEMPORAL_CALENDAR_TYPE:
     case JS_TEMPORAL_DURATION_TYPE:
     case JS_TEMPORAL_INSTANT_TYPE:

src/d8/d8.cc

@@ -1265,6 +1265,11 @@ void Shell::HostInitializeImportMetaObject(Local<Context> context,
   meta->CreateDataProperty(context, url_key, url).ToChecked();
 }
 
+MaybeLocal<Context> Shell::HostCreateShadowRealmContext(
+    Local<Context> initiator_context) {
+  return v8::Context::New(initiator_context->GetIsolate());
+}
+
 void Shell::DoHostImportModuleDynamically(void* import_data) {
   DynamicImportData* import_data_ =
       static_cast<DynamicImportData*>(import_data);
@@ -3190,6 +3195,8 @@ void Shell::Initialize(Isolate* isolate, D8Console* console,
       Shell::HostImportModuleDynamically);
   isolate->SetHostInitializeImportMetaObjectCallback(
       Shell::HostInitializeImportMetaObject);
+  isolate->SetHostCreateShadowRealmContextCallback(
+      Shell::HostCreateShadowRealmContext);
 
 #ifdef V8_FUZZILLI
   // Let the parent process (Fuzzilli) know we are ready.

src/d8/d8.h

@@ -636,6 +636,8 @@ class Shell : public i::AllStatic {
   static void HostInitializeImportMetaObject(Local<Context> context,
                                              Local<Module> module,
                                              Local<Object> meta);
+  static MaybeLocal<Context> HostCreateShadowRealmContext(
+      Local<Context> initiator_context);
 
 #ifdef V8_FUZZILLI
   static void Fuzzilli(const v8::FunctionCallbackInfo<v8::Value>& args);

src/diagnostics/objects-debug.cc

@@ -54,6 +54,7 @@
 #endif  // V8_INTL_SUPPORT
 #include "src/objects/js-regexp-inl.h"
 #include "src/objects/js-regexp-string-iterator-inl.h"
+#include "src/objects/js-shadow-realms-inl.h"
 #ifdef V8_INTL_SUPPORT
 #include "src/objects/js-relative-time-format-inl.h"
 #include "src/objects/js-segment-iterator-inl.h"
@@ -1134,6 +1135,8 @@ void JSMapIterator::JSMapIteratorVerify(Isolate* isolate) {
   CHECK(index().IsSmi());
 }
 
+USE_TORQUE_VERIFIER(JSShadowRealm)
+
 void WeakCell::WeakCellVerify(Isolate* isolate) {
   CHECK(IsWeakCell());
 

src/diagnostics/objects-printer.cc

@@ -1399,6 +1399,12 @@ void JSWeakRef::JSWeakRefPrint(std::ostream& os) {
   JSObjectPrintBody(os, *this);
 }
 
+void JSShadowRealm::JSShadowRealmPrint(std::ostream& os) {
+  JSObjectPrintHeader(os, *this, "JSShadowRealm");
+  os << "\n - native_context: " << Brief(native_context());
+  JSObjectPrintBody(os, *this);
+}
+
 void JSFinalizationRegistry::JSFinalizationRegistryPrint(std::ostream& os) {
   JSObjectPrintHeader(os, *this, "JSFinalizationRegistry");
   os << "\n - native_context: " << Brief(native_context());

src/execution/isolate.cc

@@ -4771,6 +4771,32 @@ void Isolate::SetHostInitializeImportMetaObjectCallback(
   host_initialize_import_meta_object_callback_ = callback;
 }
 
+void Isolate::SetHostCreateShadowRealmContextCallback(
+    HostCreateShadowRealmContextCallback callback) {
+  host_create_shadow_realm_context_callback_ = callback;
+}
+
+MaybeHandle<NativeContext> Isolate::RunHostCreateShadowRealmContextCallback() {
+  if (host_create_shadow_realm_context_callback_ == nullptr) {
+    Handle<Object> exception =
+        factory()->NewError(error_function(), MessageTemplate::kUnsupported);
+    Throw(*exception);
+    return kNullMaybeHandle;
+  }
+
+  v8::Local<v8::Context> api_context =
+      v8::Utils::ToLocal(Handle<Context>(native_context()));
+  v8::Local<v8::Context> shadow_realm_context;
+  ASSIGN_RETURN_ON_SCHEDULED_EXCEPTION_VALUE(
+      this, shadow_realm_context,
+      host_create_shadow_realm_context_callback_(api_context),
+      MaybeHandle<NativeContext>());
+  Handle<Context> shadow_realm_context_handle =
+      v8::Utils::OpenHandle(*shadow_realm_context);
+  DCHECK(shadow_realm_context_handle->IsNativeContext());
+  return Handle<NativeContext>::cast(shadow_realm_context_handle);
+}
+
 MaybeHandle<Object> Isolate::RunPrepareStackTraceCallback(
     Handle<Context> context, Handle<JSObject> error, Handle<JSArray> sites) {
   v8::Local<v8::Context> api_context = Utils::ToLocal(context);

src/execution/isolate.h

@@ -1753,6 +1753,10 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
   MaybeHandle<JSObject> RunHostInitializeImportMetaObjectCallback(
       Handle<SourceTextModule> module);
 
+  void SetHostCreateShadowRealmContextCallback(
+      HostCreateShadowRealmContextCallback callback);
+  MaybeHandle<NativeContext> RunHostCreateShadowRealmContextCallback();
+
   void RegisterEmbeddedFileWriter(EmbeddedFileWriterInterface* writer) {
     embedded_file_writer_ = writer;
   }
@@ -2137,6 +2141,9 @@ class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
 
   HostInitializeImportMetaObjectCallback
       host_initialize_import_meta_object_callback_ = nullptr;
+  HostCreateShadowRealmContextCallback
+      host_create_shadow_realm_context_callback_ = nullptr;
+
   base::Mutex rail_mutex_;
   double load_start_time_ms_ = 0;
 

src/flags/flag-definitions.h

@@ -306,7 +306,8 @@ DEFINE_BOOL(harmony_shipping, true, "enable all shipped harmony features")
   V(harmony_import_assertions, "harmony import assertions")                    \
   V(harmony_rab_gsab,                                                          \
     "harmony ResizableArrayBuffer / GrowableSharedArrayBuffer")                \
-  V(harmony_temporal, "Temporal")
+  V(harmony_temporal, "Temporal")                                              \
+  V(harmony_shadow_realm, "harmony ShadowRealm")
 
 #ifdef V8_INTL_SUPPORT
 #define HARMONY_INPROGRESS(V) HARMONY_INPROGRESS_BASE(V)

src/init/bootstrapper.cc

@@ -52,6 +52,7 @@
 #endif  // V8_INTL_SUPPORT
 #include "src/objects/js-regexp-string-iterator.h"
 #include "src/objects/js-regexp.h"
+#include "src/objects/js-shadow-realms.h"
 #ifdef V8_INTL_SUPPORT
 #include "src/objects/js-relative-time-format.h"
 #include "src/objects/js-segment-iterator.h"
@@ -4407,6 +4408,30 @@ EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(harmony_intl_best_fit_matcher)
 
 #undef EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE
 
+void Genesis::InitializeGlobal_harmony_shadow_realm() {
+  if (!FLAG_harmony_shadow_realm) return;
+  // -- S h a d o w R e a l m
+  // #sec-shadowrealm-objects
+  Handle<JSGlobalObject> global(native_context()->global_object(), isolate());
+  Handle<JSFunction> shadow_realm_fun = InstallFunction(
+      isolate_, global, "ShadowRealm", JS_SHADOW_REALM_TYPE,
+      JSShadowRealm::kHeaderSize, 0, factory()->the_hole_value(),
+      Builtin::kShadowRealmConstructor);
+  shadow_realm_fun->shared().set_length(0);
+  shadow_realm_fun->shared().DontAdaptArguments();
+
+  // Setup %ShadowRealmPrototype%.
+  Handle<JSObject> prototype(
+      JSObject::cast(shadow_realm_fun->instance_prototype()), isolate());
+
+  InstallToStringTag(isolate_, prototype, factory()->ShadowRealm_string());
+
+  SimpleInstallFunction(isolate_, prototype, "evaluate",
+                        Builtin::kShadowRealmPrototypeEvaluate, 1, true);
+  SimpleInstallFunction(isolate_, prototype, "importValue",
+                        Builtin::kShadowRealmPrototypeImportValue, 2, true);
+}
+
 void Genesis::InitializeGlobal_harmony_array_find_last() {
   if (!FLAG_harmony_array_find_last) return;
 

src/init/heap-symbols.h

@@ -367,6 +367,7 @@
   V(_, set_string, "set")                                             \
   V(_, SetIterator_string, "Set Iterator")                            \
   V(_, setPrototypeOf_string, "setPrototypeOf")                       \
+  V(_, ShadowRealm_string, "ShadowRealm")                             \
   V(_, SharedArrayBuffer_string, "SharedArrayBuffer")                 \
   V(_, sign_string, "sign")                                           \
   V(_, smallestUnit_string, "smallestUnit")                           \

src/objects/all-objects-inl.h

@@ -47,6 +47,7 @@
 #include "src/objects/js-proxy-inl.h"
 #include "src/objects/js-regexp-inl.h"
 #include "src/objects/js-regexp-string-iterator-inl.h"
+#include "src/objects/js-shadow-realms-inl.h"
 #include "src/objects/js-temporal-objects-inl.h"
 #include "src/objects/js-weak-refs-inl.h"
 #include "src/objects/literal-objects-inl.h"

src/objects/js-function.cc

@@ -570,6 +570,7 @@ bool CanSubclassHaveInobjectProperties(InstanceType instance_type) {
     case JS_PROMISE_TYPE:
     case JS_REG_EXP_TYPE:
     case JS_SET_TYPE:
+    case JS_SHADOW_REALM_TYPE:
     case JS_SPECIAL_API_OBJECT_TYPE:
     case JS_TYPED_ARRAY_TYPE:
     case JS_PRIMITIVE_WRAPPER_TYPE:

src/objects/js-objects.cc

@@ -52,6 +52,7 @@
 #include "src/objects/js-promise.h"
 #include "src/objects/js-regexp-inl.h"
 #include "src/objects/js-regexp-string-iterator.h"
+#include "src/objects/js-shadow-realms.h"
 #ifdef V8_INTL_SUPPORT
 #include "src/objects/js-relative-time-format.h"
 #include "src/objects/js-segment-iterator.h"
@@ -2334,6 +2335,8 @@ int JSObject::GetHeaderSize(InstanceType type,
       return JSObject::kHeaderSize;
     case JS_ERROR_TYPE:
       return JSObject::kHeaderSize;
+    case JS_SHADOW_REALM_TYPE:
+      return JSShadowRealm::kHeaderSize;
     case JS_STRING_ITERATOR_TYPE:
       return JSStringIterator::kHeaderSize;
     case JS_MODULE_NAMESPACE_TYPE:

src/objects/js-shadow-realms-inl.h

+// Copyright 2021 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_JS_SHADOW_REALMS_INL_H_
+#define V8_OBJECTS_JS_SHADOW_REALMS_INL_H_
+
+#include "src/api/api-inl.h"
+#include "src/heap/heap-write-barrier-inl.h"
+#include "src/objects/js-shadow-realms.h"
+#include "src/objects/smi-inl.h"
+
+// Has to be the last include (doesn't have include guards):
+#include "src/objects/object-macros.h"
+
+namespace v8 {
+namespace internal {
+
+#include "torque-generated/src/objects/js-shadow-realms-tq-inl.inc"
+
+TQ_OBJECT_CONSTRUCTORS_IMPL(JSShadowRealm)
+
+}  // namespace internal
+}  // namespace v8
+
+#include "src/objects/object-macros-undef.h"
+
+#endif  // V8_OBJECTS_JS_SHADOW_REALMS_INL_H_

src/objects/js-shadow-realms.h

+// Copyright 2021 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_JS_SHADOW_REALMS_H_
+#define V8_OBJECTS_JS_SHADOW_REALMS_H_
+
+#include "src/objects/js-objects.h"
+#include "torque-generated/bit-fields.h"
+
+// Has to be the last include (doesn't have include guards):
+#include "src/objects/object-macros.h"
+
+namespace v8 {
+namespace internal {
+
+class NativeContext;
+
+#include "torque-generated/src/objects/js-shadow-realms-tq.inc"
+
+// ShadowRealm object from the JS ShadowRealm spec proposal:
+// https://github.com/tc39/proposal-shadowrealm
+class JSShadowRealm
+    : public TorqueGeneratedJSShadowRealm<JSShadowRealm, JSObject> {
+ public:
+  DECL_PRINTER(JSShadowRealm)
+  EXPORT_DECL_VERIFIER(JSShadowRealm)
+
+  class BodyDescriptor;
+
+  TQ_OBJECT_CONSTRUCTORS(JSShadowRealm)
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#include "src/objects/object-macros-undef.h"
+
+#endif  // V8_OBJECTS_JS_SHADOW_REALMS_H_

src/objects/js-shadow-realms.tq

+// Copyright 2021 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.
+
+extern class JSShadowRealm extends JSObject { native_context: NativeContext; }

src/objects/map.cc

@@ -272,6 +272,7 @@ VisitorId Map::GetVisitorId(Map map) {
     case JS_SET_PROTOTYPE_TYPE:
     case JS_SET_TYPE:
     case JS_SET_VALUE_ITERATOR_TYPE:
+    case JS_SHADOW_REALM_TYPE:
     case JS_STRING_ITERATOR_PROTOTYPE_TYPE:
     case JS_STRING_ITERATOR_TYPE:
     case JS_TEMPORAL_CALENDAR_TYPE:

src/objects/object-list-macros.h

@@ -158,6 +158,7 @@ class ZoneForwardList;
   V(JSRegExpStringIterator)                    \
   V(JSSet)                                     \
   V(JSSetIterator)                             \
+  V(JSShadowRealm)                             \
   V(JSSpecialObject)                           \
   V(JSStringIterator)                          \
   V(JSTemporalCalendar)                        \

src/objects/objects-body-descriptors-inl.h

@@ -1153,6 +1153,7 @@ auto BodyDescriptorApply(InstanceType type, Args&&... args) {
     case JS_SET_TYPE:
     case JS_SET_VALUE_ITERATOR_TYPE:
     case JS_SPECIAL_API_OBJECT_TYPE:
+    case JS_SHADOW_REALM_TYPE:
     case JS_STRING_ITERATOR_PROTOTYPE_TYPE:
     case JS_STRING_ITERATOR_TYPE:
     case JS_TEMPORAL_CALENDAR_TYPE:

src/objects/objects.h

@@ -64,6 +64,7 @@
 //         - JSMessageObject
 //         - JSRegExp
 //         - JSSetIterator
+//         - JSShadowRealm
 //         - JSStringIterator
 //         - JSTemporalCalendar
 //         - JSTemporalDuration

test/cctest/test-api.cc

@@ -26600,6 +26600,90 @@ TEST(ImportMetaThrowHandled) {
   CHECK(!try_catch.HasCaught());
 }
 
+v8::MaybeLocal<v8::Context> HostCreateShadowRealmContextCallbackStatic(
+    v8::Local<v8::Context> initiator_context) {
+  CHECK(!initiator_context.IsEmpty());
+  return v8::Context::New(initiator_context->GetIsolate());
+}
+
+TEST(CreateShadowRealmContextHostNotSupported) {
+  i::FLAG_harmony_shadow_realm = true;
+  LocalContext context;
+  v8::Isolate* isolate = context->GetIsolate();
+  v8::HandleScope scope(isolate);
+
+  Local<String> url = v8_str("www.google.com");
+  Local<String> source_text = v8_str("new ShadowRealm()");
+  v8::ScriptOrigin origin(isolate, url, 0, 0, false, -1, Local<v8::Value>(),
+                          false, false, false);
+  v8::ScriptCompiler::Source source(source_text, origin);
+  Local<Script> script =
+      v8::ScriptCompiler::Compile(context.local(), &source).ToLocalChecked();
+
+  v8::TryCatch try_catch(isolate);
+  v8::MaybeLocal<v8::Value> result = script->Run(context.local());
+  CHECK(try_catch.HasCaught());
+  CHECK(result.IsEmpty());
+  CHECK(v8_str("Error: Not supported")
+            ->Equals(isolate->GetCurrentContext(),
+                     try_catch.Exception()
+                         ->ToString(isolate->GetCurrentContext())
+                         .ToLocalChecked())
+            .FromJust());
+}
+
+TEST(CreateShadowRealmContext) {
+  i::FLAG_harmony_shadow_realm = true;
+  LocalContext context;
+  v8::Isolate* isolate = context->GetIsolate();
+  v8::HandleScope scope(isolate);
+
+  isolate->SetHostCreateShadowRealmContextCallback(
+      HostCreateShadowRealmContextCallbackStatic);
+
+  Local<String> url = v8_str("www.google.com");
+  Local<String> source_text = v8_str("new ShadowRealm()");
+  v8::ScriptOrigin origin(isolate, url, 0, 0, false, -1, Local<v8::Value>(),
+                          false, false, false);
+  v8::ScriptCompiler::Source source(source_text, origin);
+  Local<Script> script =
+      v8::ScriptCompiler::Compile(context.local(), &source).ToLocalChecked();
+
+  Local<Value> result = script->Run(context.local()).ToLocalChecked();
+  CHECK(result->IsObject());
+  i::Handle<i::Object> object = v8::Utils::OpenHandle(*result);
+  CHECK(object->IsJSShadowRealm());
+}
+
+v8::MaybeLocal<v8::Context> HostCreateShadowRealmContextCallbackThrow(
+    v8::Local<v8::Context> initiator_context) {
+  CcTest::isolate()->ThrowException(v8_num(42));
+  return v8::MaybeLocal<v8::Context>();
+}
+
+TEST(CreateShadowRealmContextThrow) {
+  i::FLAG_harmony_shadow_realm = true;
+  LocalContext context;
+  v8::Isolate* isolate = context->GetIsolate();
+  v8::HandleScope scope(isolate);
+
+  isolate->SetHostCreateShadowRealmContextCallback(
+      HostCreateShadowRealmContextCallbackThrow);
+
+  Local<String> url = v8_str("www.google.com");
+  Local<String> source_text = v8_str("new ShadowRealm()");
+  v8::ScriptOrigin origin(isolate, url, 0, 0, false, -1, Local<v8::Value>(),
+                          false, false, false);
+  v8::ScriptCompiler::Source source(source_text, origin);
+  Local<Script> script =
+      v8::ScriptCompiler::Compile(context.local(), &source).ToLocalChecked();
+
+  v8::TryCatch try_catch(isolate);
+  CHECK(script->Run(context.local()).IsEmpty());
+  CHECK(try_catch.HasCaught());
+  CHECK(try_catch.Exception()->StrictEquals(v8_num(42)));
+}
+
 TEST(GetModuleNamespace) {
   LocalContext context;
   v8::Isolate* isolate = context->GetIsolate();

test/test262/test262.status

@@ -2673,24 +2673,12 @@
 
 
   # https://bugs.chromium.org/p/v8/issues/detail?id=11989
-  'built-ins/ShadowRealm/constructor': [FAIL],
-  'built-ins/ShadowRealm/descriptor': [FAIL],
-  'built-ins/ShadowRealm/extensibility': [FAIL],
-  'built-ins/ShadowRealm/instance': [FAIL],
-  'built-ins/ShadowRealm/instance-extensibility': [FAIL],
-  'built-ins/ShadowRealm/length': [FAIL],
-  'built-ins/ShadowRealm/name': [FAIL],
-  'built-ins/ShadowRealm/proto': [FAIL],
-  'built-ins/ShadowRealm/prototype/evaluate/descriptor': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/errors-from-the-other-realm-is-wrapped-into-a-typeerror': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/globalthis-available-properties': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/globalthis-config-only-properties': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/globalthis-orginary-object': [FAIL],
-  'built-ins/ShadowRealm/prototype/evaluate/length': [FAIL],
-  'built-ins/ShadowRealm/prototype/evaluate/name': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/no-conditional-strict-mode': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/not-constructor': [FAIL],
-  'built-ins/ShadowRealm/prototype/evaluate/proto': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/returns-primitive-values': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/returns-proxy-callable-object': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/returns-symbol-values': [FAIL],
@@ -2717,20 +2705,13 @@
   'built-ins/ShadowRealm/prototype/evaluate/wrapped-function-throws-typeerror-on-non-primitive-arguments': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/wrapped-function-throws-typeerror-on-non-primitive-returns': [FAIL],
   'built-ins/ShadowRealm/prototype/evaluate/nested-realms': [FAIL],
-  'built-ins/ShadowRealm/prototype/importValue/descriptor': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/exportName-tostring': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/import-value': [FAIL],
-  'built-ins/ShadowRealm/prototype/importValue/length': [FAIL],
-  'built-ins/ShadowRealm/prototype/importValue/name': [FAIL],
-  'built-ins/ShadowRealm/prototype/importValue/not-constructor': [FAIL],
-  'built-ins/ShadowRealm/prototype/importValue/proto': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/specifier-tostring': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/throws-if-import-value-does-not-exist': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/throws-typeerror-import-syntax-error': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/throws-typeerror-import-throws': [FAIL],
   'built-ins/ShadowRealm/prototype/importValue/validates-realm-object': [FAIL],
-  'built-ins/ShadowRealm/prototype/proto': [FAIL],
-  'built-ins/ShadowRealm/prototype/Symbol.toStringTag': [FAIL],
 
   # https://bugs.chromium.org/p/v8/issues/detail?id=12085
   'language/statements/class/subclass/derived-class-return-override-catch-finally': [FAIL],

test/test262/testcfg.py

@@ -61,6 +61,7 @@ FEATURE_FLAGS = {
   'resizable-arraybuffer': '--harmony-rab-gsab',
   'Temporal': '--harmony-temporal',
   'array-find-from-last': '--harmony_array_find_last',
+  'ShadowRealm': '--harmony-shadow-realm',
 }
 
 SKIPPED_FEATURES = set([])