[es6] Partially implement Reflect.setPrototypeOf.

src/objects.h

 // Copyright 2012 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_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 1783 matching lines @@
 
 enum KeyFilter { SKIP_SYMBOLS, INCLUDE_SYMBOLS };
 
 
 enum GetKeysConversion { KEEP_NUMBERS, CONVERT_TO_STRING };
 
 
 enum ShouldThrow { THROW_ON_ERROR, DONT_THROW };
 
 
+#define RETURN_FAILURE(isolate, should_throw, call) \
+  do {                                              \
+    if ((should_throw) == DONT_THROW) {             \
+      return Just(false);                           \
+    } else {                                        \
+      isolate->Throw(*isolate->factory()->call);    \
+      return Nothing<bool>();                       \
+    }                                               \
+  } while (false)
+
+
+#define MAYBE_RETURN(call, value)         \
+  do {                                    \
+    if ((call).IsNothing()) return value; \
+  } while (false)
+
+#define MAYBE_RETURN_NULL(call) MAYBE_RETURN(call, MaybeHandle<Object>())
+
+
 // JSReceiver includes types on which properties can be defined, i.e.,
 // JSObject and JSProxy.
 class JSReceiver: public HeapObject {
  public:
   DECLARE_CAST(JSReceiver)
 
   // ES6 section 7.1.1 ToPrimitive
   MUST_USE_RESULT static MaybeHandle<Object> ToPrimitive(
       Handle<JSReceiver> receiver,
       ToPrimitiveHint hint = ToPrimitiveHint::kDefault);
@@ skipping 73 matching lines @@
   GetOwnPropertyAttributes(Handle<JSReceiver> object, Handle<Name> name);
 
   MUST_USE_RESULT static inline Maybe<PropertyAttributes> GetElementAttributes(
       Handle<JSReceiver> object, uint32_t index);
   MUST_USE_RESULT static inline Maybe<PropertyAttributes>
   GetOwnElementAttributes(Handle<JSReceiver> object, uint32_t index);
 
   MUST_USE_RESULT static Maybe<PropertyAttributes> GetPropertyAttributes(
       LookupIterator* it);
 
+  // Set the object's prototype (only JSReceiver and null are allowed values).
+  MUST_USE_RESULT static Maybe<bool> SetPrototype(Handle<JSReceiver> object,
+                                                  Handle<Object> value,
+                                                  bool from_javascript,
+                                                  ShouldThrow should_throw);
+
 
   static Handle<Object> GetDataProperty(Handle<JSReceiver> object,
                                         Handle<Name> name);
   static Handle<Object> GetDataProperty(LookupIterator* it);
 
 
   // Retrieves a permanent object identity hash code. The undefined value might
   // be returned in case no hash was created yet.
   inline Object* GetIdentityHash();
 
@@ skipping 401 matching lines @@
 
   // Access to in object properties.
   inline int GetInObjectPropertyOffset(int index);
   inline Object* InObjectPropertyAt(int index);
   inline Object* InObjectPropertyAtPut(int index,
                                        Object* value,
                                        WriteBarrierMode mode
                                        = UPDATE_WRITE_BARRIER);
 
   // Set the object's prototype (only JSReceiver and null are allowed values).
-  MUST_USE_RESULT static MaybeHandle<Object> SetPrototype(
-      Handle<JSObject> object, Handle<Object> value, bool from_javascript);
+  MUST_USE_RESULT static Maybe<bool> SetPrototype(Handle<JSObject> object,
+                                                  Handle<Object> value,
+                                                  bool from_javascript,
+                                                  ShouldThrow should_throw);
 
   // Initializes the body after properties slot, properties slot is
   // initialized by set_properties.  Fill the pre-allocated fields with
   // pre_allocated_value and the rest with filler_value.
   // Note: this call does not update write barrier, the caller is responsible
   // to ensure that |filler_value| can be collected without WB here.
   inline void InitializeBody(Map* map,
                              Object* pre_allocated_value,
                              Object* filler_value);
 
@@ skipping 185 matching lines @@
 
   static Handle<SeededNumberDictionary> GetNormalizedElementDictionary(
       Handle<JSObject> object, Handle<FixedArrayBase> elements);
 
   // Helper for fast versions of preventExtensions, seal, and freeze.
   // attrs is one of NONE, SEALED, or FROZEN (depending on the operation).
   template <PropertyAttributes attrs>
   MUST_USE_RESULT static Maybe<bool> PreventExtensionsWithTransition(
       Handle<JSObject> object, ShouldThrow should_throw);
 
-  MUST_USE_RESULT static MaybeHandle<Object> SetPrototypeUnobserved(
-      Handle<JSObject> object, Handle<Object> value, bool from_javascript);
+  MUST_USE_RESULT static Maybe<bool> SetPrototypeUnobserved(
+      Handle<JSObject> object, Handle<Object> value, bool from_javascript,
+      ShouldThrow should_throw);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSObject);
 };
 
 
 // Common superclass for FixedArrays that allow implementations to share
 // common accessors and some code paths.
 class FixedArrayBase: public HeapObject {
  public:
   // [length]: length of the array.
@@ skipping 8251 matching lines @@
   // (elements + properties) in the current level.
   int levelLength_;
 
   DISALLOW_COPY_AND_ASSIGN(KeyAccumulator);
 };
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_