Expose v8::Function::IsBuiltin to public API.

test/cctest/test-api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 17519 matching lines @@
   v8::Script::Compile(script, &origin)->Run();
   v8::Local<v8::Function> foo = v8::Local<v8::Function>::Cast(
       env->Global()->Get(v8::String::New("foo")));
   v8::Local<v8::Function> bar = v8::Local<v8::Function>::Cast(
       env->Global()->Get(v8::String::New("bar")));
   CHECK_EQ(14, foo->GetScriptColumnNumber());
   CHECK_EQ(17, bar->GetScriptColumnNumber());
 }
 
 
+THREADED_TEST(FunctionIsBuiltin) {
+  LocalContext env;
+  v8::HandleScope scope(env->GetIsolate());
+  v8::Local<v8::Function> f;
+  f = v8::Local<v8::Function>::Cast(CompileRun("Math.floor"));
+  CHECK(f->IsBuiltin());
+  f = v8::Local<v8::Function>::Cast(CompileRun("Object"));
+  CHECK(f->IsBuiltin());
+  f = v8::Local<v8::Function>::Cast(CompileRun("Object.__defineSetter__"));
+  CHECK(f->IsBuiltin());
+  f = v8::Local<v8::Function>::Cast(CompileRun("Array.prototype.toString"));
+  CHECK(f->IsBuiltin());
+  f = v8::Local<v8::Function>::Cast(CompileRun("function a() {}; a;"));
+  CHECK(!f->IsBuiltin());
+}
+
+
 THREADED_TEST(FunctionGetScriptId) {
   LocalContext env;
   v8::HandleScope scope(env->GetIsolate());
   v8::ScriptOrigin origin = v8::ScriptOrigin(v8::String::New("test"),
       v8::Integer::New(3), v8::Integer::New(2));
   v8::Handle<v8::String> scriptSource = v8::String::New(
       "function foo() {}\n\n     function bar() {}");
   v8::Local<v8::Script> script(v8::Script::Compile(scriptSource, &origin));
   script->Run();
   v8::Local<v8::Function> foo = v8::Local<v8::Function>::Cast(
@@ skipping 3080 matching lines @@
   }
   for (int i = 0; i < runs; i++) {
     Local<String> expected;
     if (i != 0) {
       CHECK_EQ(v8_str("escape value"), values[i]);
     } else {
       CHECK(values[i].IsEmpty());
     }
   }
 }