Add RemovePrototype to FunctionTemplate

This allows functions created from a FunctionTemplate to not have a
prototype property, which is required by DOM methods.

R=mstarzinger@chromium.org
BUG=chromium:272440

Review URL: https://codereview.chromium.org/22990003

Patch from Erik Arvidsson <arv@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16341 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

include/v8.h

@@ -3430,6 +3430,12 @@ class V8_EXPORT FunctionTemplate : public Template {
    */
   void ReadOnlyPrototype();
 
+  /**
+   * Removes the prototype property from functions created from this
+   * FunctionTemplate.
+   */
+  void RemovePrototype();
+
   /**
    * Returns true if the given object is an instance of this function
    * template.

src/api.cc

@@ -1451,6 +1451,17 @@ void FunctionTemplate::ReadOnlyPrototype() {
   Utils::OpenHandle(this)->set_read_only_prototype(true);
 }
 
+
+void FunctionTemplate::RemovePrototype() {
+  i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate();
+  if (IsDeadCheck(isolate, "v8::FunctionTemplate::RemovePrototype()")) {
+    return;
+  }
+  ENTER_V8(isolate);
+  Utils::OpenHandle(this)->set_remove_prototype(true);
+}
+
+
 template<
     typename Getter,
     typename Setter,

src/apinatives.js

@@ -75,22 +75,26 @@ function InstantiateFunction(data, name) {
       var fun = %CreateApiFunction(data);
       if (name) %FunctionSetName(fun, name);
       cache[serialNumber] = fun;
-      var prototype = %GetTemplateField(data, kApiPrototypeTemplateOffset);
       var flags = %GetTemplateField(data, kApiFlagOffset);
-      // Note: Do not directly use an object template as a condition, our
-      // internal ToBoolean doesn't handle that!
-      fun.prototype = typeof prototype === 'undefined' ?
-          {} : Instantiate(prototype);
-      if (flags & (1 << kReadOnlyPrototypeBit)) {
-        %FunctionSetReadOnlyPrototype(fun);
-      }
-      %SetProperty(fun.prototype, "constructor", fun, DONT_ENUM);
-      var parent = %GetTemplateField(data, kApiParentTemplateOffset);
-      // Note: Do not directly use a function template as a condition, our
-      // internal ToBoolean doesn't handle that!
-      if (!(typeof parent === 'undefined')) {
-        var parent_fun = Instantiate(parent);
-        %SetPrototype(fun.prototype, parent_fun.prototype);
+      if (flags & (1 << kRemovePrototypeBit)) {
+        %FunctionRemovePrototype(fun);
+      } else {
+        var prototype = %GetTemplateField(data, kApiPrototypeTemplateOffset);
+        // Note: Do not directly use an object template as a condition, our
+        // internal ToBoolean doesn't handle that!
+        fun.prototype = typeof prototype === 'undefined' ?
+            {} : Instantiate(prototype);
+        if (flags & (1 << kReadOnlyPrototypeBit)) {
+          %FunctionSetReadOnlyPrototype(fun);
+        }
+        %SetProperty(fun.prototype, "constructor", fun, DONT_ENUM);
+        var parent = %GetTemplateField(data, kApiParentTemplateOffset);
+        // Note: Do not directly use a function template as a condition, our
+        // internal ToBoolean doesn't handle that!
+        if (!(typeof parent === 'undefined')) {
+          var parent_fun = Instantiate(parent);
+          %SetPrototype(fun.prototype, parent_fun.prototype);
+        }
       }
       ConfigureTemplateInstance(fun, data);
     } catch (e) {

src/macros.py

@@ -67,7 +67,8 @@ const msPerMonth       = 2592000000;
 
 # For apinatives.js
 const kUninitialized = -1;
-const kReadOnlyPrototypeBit = 3;  # For FunctionTemplateInfo, matches objects.h
+const kReadOnlyPrototypeBit = 3;
+const kRemovePrototypeBit = 4;  # For FunctionTemplateInfo, matches objects.h
 
 # Note: kDayZeroInJulianDay = ToJulianDay(1970, 0, 1).
 const kInvalidDate        = 'Invalid Date';

src/objects-inl.h

@@ -4576,6 +4576,8 @@ BOOL_ACCESSORS(FunctionTemplateInfo, flag, needs_access_check,
                kNeedsAccessCheckBit)
 BOOL_ACCESSORS(FunctionTemplateInfo, flag, read_only_prototype,
                kReadOnlyPrototypeBit)
+BOOL_ACCESSORS(FunctionTemplateInfo, flag, remove_prototype,
+               kRemovePrototypeBit)
 BOOL_ACCESSORS(SharedFunctionInfo, start_position_and_type, is_expression,
                kIsExpressionBit)
 BOOL_ACCESSORS(SharedFunctionInfo, start_position_and_type, is_toplevel,

src/objects.h

@@ -9874,6 +9874,7 @@ class FunctionTemplateInfo: public TemplateInfo {
   // requires access check.
   DECL_BOOLEAN_ACCESSORS(needs_access_check)
   DECL_BOOLEAN_ACCESSORS(read_only_prototype)
+  DECL_BOOLEAN_ACCESSORS(remove_prototype)
 
   static inline FunctionTemplateInfo* cast(Object* obj);
 
@@ -9909,6 +9910,7 @@ class FunctionTemplateInfo: public TemplateInfo {
   static const int kUndetectableBit      = 1;
   static const int kNeedsAccessCheckBit  = 2;
   static const int kReadOnlyPrototypeBit = 3;
+  static const int kRemovePrototypeBit   = 4;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(FunctionTemplateInfo);
 };

test/cctest/test-api.cc

@@ -9608,6 +9608,26 @@ THREADED_TEST(SetPrototypeThrows) {
 }
 
 
+THREADED_TEST(FunctionRemovePrototype) {
+  LocalContext context;
+  v8::HandleScope handle_scope(context->GetIsolate());
+
+  Local<v8::FunctionTemplate> t1 = v8::FunctionTemplate::New();
+  t1->RemovePrototype();
+  Local<v8::Function> fun = t1->GetFunction();
+  context->Global()->Set(v8_str("fun"), fun);
+  CHECK(!CompileRun("'prototype' in fun")->BooleanValue());
+
+  v8::TryCatch try_catch;
+  CompileRun("new fun()");
+  CHECK(try_catch.HasCaught());
+
+  try_catch.Reset();
+  fun->NewInstance();
+  CHECK(try_catch.HasCaught());
+}
+
+
 THREADED_TEST(GetterSetterExceptions) {
   LocalContext context;
   v8::HandleScope handle_scope(context->GetIsolate());