[api] Expose FunctionCallbackInfo::NewTarget

src/builtins.h

 // Copyright 2011 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_BUILTINS_H_
 #define V8_BUILTINS_H_
 
 #include "src/base/flags.h"
 #include "src/handles.h"
 
@@ skipping 143 matching lines @@
   V(ReflectIsExtensible, kNone)                                \
   V(ReflectOwnKeys, kNone)                                     \
   V(ReflectPreventExtensions, kNone)                           \
   V(ReflectSet, kNone)                                         \
   V(ReflectSetPrototypeOf, kNone)                              \
                                                                \
   V(SymbolConstructor, kNone)                                  \
   V(SymbolConstructor_ConstructStub, kTarget)                  \
                                                                \
   V(HandleApiCall, kTarget)                                    \
-  V(HandleApiCallConstruct, kTarget)                           \
+  V(HandleApiCallConstruct, kTargetAndNewTarget)               \

[Benedikt Meurer, 2016/04/23 11:57:47]

This is not sufficient, as the callsite is custom code in builtins-x64.cc and so
you need to make sure to manually add NewTarget there.

[Benedikt Meurer, 2016/04/23 18:21:45]

Actually this is nonsense. The JSConstructStubHelper passes NewTarget in the
appropriate register and the builtin adaptor pushes it, so everything works fine
the way it is currently.

[adamk, 2016/04/25 22:59:55]

Yup, this seems to work just fine.

   V(HandleApiCallAsFunction, kNone)                            \
   V(HandleApiCallAsConstructor, kNone)                         \
                                                                \
   V(RestrictedFunctionPropertiesThrower, kNone)                \
   V(RestrictedStrictArgumentsPropertiesThrower, kNone)
 
 // Define list of builtins implemented in assembly.
 #define BUILTIN_LIST_A(V)                                                      \
   V(ArgumentsAdaptorTrampoline, BUILTIN, UNINITIALIZED, kNoExtraICState)       \
                                                                                \
@@ skipping 498 matching lines @@
   friend class BuiltinFunctionTable;
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(Builtins);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_BUILTINS_H_