Introduce extras export object.

BUG=

Review URL: https://codereview.chromium.org/1140333003

Cr-Commit-Position: refs/heads/master@{#28499}

build/standalone.gypi

@@ -100,6 +100,9 @@
     'msan%': '<(msan)',
     'tsan%': '<(tsan)',
 
+    # Add a simple extra solely for the purpose of the cctests
+    'v8_extra_library_files': ['../test/cctest/test-extra.js'],
+
     # .gyp files or targets should set v8_code to 1 if they build V8 specific
     # code, as opposed to external code.  This variable is used to control such
     # things as the set of warnings to enable, and whether warnings are treated

include/v8.h

@@ -6430,6 +6430,12 @@ class V8_EXPORT Context {
    */
   V8_INLINE Local<Value> GetEmbedderData(int index);
 
+  /**
+   * Gets the exports object used by V8 extras. Extra natives get a reference
+   * to this object and can use it to export functionality.
+   */
+  Local<Object> GetExtrasExportsObject();
+
   /**
    * Sets the embedder data with the given index, growing the data as
    * needed. Note that index 0 currently has a special meaning for Chrome's

src/api.cc

@@ -5495,6 +5495,14 @@ void Context::DetachGlobal() {
 }
 
 
+Local<v8::Object> Context::GetExtrasExportsObject() {
+  i::Handle<i::Context> context = Utils::OpenHandle(this);
+  i::Isolate* isolate = context->GetIsolate();
+  i::Handle<i::JSObject> exports(context->extras_exports_object(), isolate);
+  return Utils::ToLocal(exports);
+}
+
+
 void Context::AllowCodeGenerationFromStrings(bool allow) {
   i::Handle<i::Context> context = Utils::OpenHandle(this);
   i::Isolate* isolate = context->GetIsolate();

src/bootstrapper.cc

@@ -1472,7 +1472,7 @@ bool Genesis::CompileExtraBuiltin(Isolate* isolate, int index) {
   Handle<String> source_code =
       isolate->bootstrapper()->SourceLookup<ExtraNatives>(index);
   Handle<Object> global = isolate->global_object();
-  Handle<Object> exports = isolate->builtin_exports_object();
+  Handle<Object> exports = isolate->extras_exports_object();
   Handle<Object> args[] = {global, exports};
   return CompileNative(isolate, name, source_code, arraysize(args), args);
 }
@@ -1925,12 +1925,19 @@ bool Genesis::InstallNatives() {
       factory()->NewJSObject(isolate()->object_function());
   JSObject::NormalizeProperties(shared, CLEAR_INOBJECT_PROPERTIES, 16,
                                 "container to share between native scripts");
+
   Handle<JSObject> builtin_exports =
       factory()->NewJSObject(isolate()->object_function());
   JSObject::NormalizeProperties(builtin_exports, CLEAR_INOBJECT_PROPERTIES, 16,
                                 "container to export to experimental natives");
   native_context()->set_builtin_exports_object(*builtin_exports);
 
+  Handle<JSObject> extras_exports =
+      factory()->NewJSObject(isolate()->object_function());
+  JSObject::NormalizeProperties(extras_exports, CLEAR_INOBJECT_PROPERTIES, 2,
+                                "container to export to extra natives");
+  native_context()->set_extras_exports_object(*extras_exports);
+
   if (FLAG_expose_natives_as != NULL) {
     Handle<String> shared_key = factory()->NewStringFromAsciiChecked("shared");
     JSObject::AddProperty(builtins, shared_key, shared, NONE);

src/contexts.h

@@ -188,7 +188,8 @@ enum BindingFlags {
   V(SET_ITERATOR_MAP_INDEX, Map, set_iterator_map)                             \
   V(ARRAY_VALUES_ITERATOR_INDEX, JSFunction, array_values_iterator)            \
   V(SCRIPT_CONTEXT_TABLE_INDEX, ScriptContextTable, script_context_table)      \
-  V(BUILTIN_EXPORTS_OBJECT_INDEX, Object, builtin_exports_object)
+  V(BUILTIN_EXPORTS_OBJECT_INDEX, Object, builtin_exports_object)              \
+  V(EXTRAS_EXPORTS_OBJECT_INDEX, JSObject, extras_exports_object)
 
 
 // A table of all script contexts. Every loaded top-level script with top-level
@@ -428,6 +429,7 @@ class Context: public FixedArray {
     MAP_CACHE_INDEX,
     TO_LENGTH_FUN_INDEX,
     BUILTIN_EXPORTS_OBJECT_INDEX,
+    EXTRAS_EXPORTS_OBJECT_INDEX,
 
     // Properties from here are treated as weak references by the full GC.
     // Scavenge treats them as strong references.

src/runtime/runtime-test.cc

@@ -372,7 +372,8 @@ RUNTIME_FUNCTION(Runtime_AbortJS) {
 
 RUNTIME_FUNCTION(Runtime_NativeScriptsCount) {
   DCHECK(args.length() == 0);
-  return Smi::FromInt(Natives::GetBuiltinsCount());
+  return Smi::FromInt(Natives::GetBuiltinsCount() +
+                      ExtraNatives::GetBuiltinsCount());
 }
 
 

test/cctest/test-api.cc

@@ -21106,3 +21106,21 @@ TEST(StrongModeArityCallFromApi2) {
     CHECK(!try_catch.HasCaught());
   }
 }
+
+
+TEST(ExtrasExportsObject) {
+  v8::Isolate* isolate = CcTest::isolate();
+  v8::HandleScope handle_scope(isolate);
+  LocalContext env;
+
+  // standalone.gypi ensures we include the test-extra.js file, which should
+  // add the testExtraShouldReturnFive export
+  v8::Local<v8::Object> exports = env->GetExtrasExportsObject();
+
+  auto func =
+      exports->Get(v8_str("testExtraShouldReturnFive")).As<v8::Function>();
+  auto undefined = v8::Undefined(isolate);
+  auto result = func->Call(undefined, 0, {}).As<v8::Number>();
+
+  CHECK(result->Value() == 5.0);
+}

test/cctest/test-extra.js

+// Copyright 2015 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.
+
+(function (global, exports) {
+  'use strict';
+  exports.testExtraShouldReturnFive = function () {
+    return 5;
+  };
+})