v8/test/cctest/test-api-accessors.cc
vogelheim ed110a1715 Allow JavaScript accessors on API objects.
(This is somewhat experimental; hence protected by #ifdef.)

R=epertoso@chromium.org, jochen@chromium.org
BUG=chromium:508898
LOG=N

Review URL: https://codereview.chromium.org/1367953002

Cr-Commit-Position: refs/heads/master@{#31002}
2015-09-29 11:16:14 +00:00

94 lines
3.1 KiB
C++

// 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.
// TODO(jochen): Remove this after the setting is turned on globally.
#define V8_IMMINENT_DEPRECATION_WARNINGS
#include "test/cctest/cctest.h"
#include "include/v8.h"
#ifdef V8_JS_ACCESSORS
static void CppAccessor(const v8::FunctionCallbackInfo<v8::Value>& info) {
info.GetReturnValue().Set(42);
}
static const char* JsAccessor =
"function firstChildJS(value) { return 41; }; firstChildJS";
TEST(JavascriptAccessors) {
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
LocalContext env;
// We emulate Embedder-created DOM Node instances. Specifically:
// - 'parent': FunctionTemplate ~= DOM Node superclass
// - 'child': FunctionTemplate ~= a specific DOM node type, like a <div />
//
// We'll install both a C++-based and a JS-based accessor on the parent,
// and expect it to be callable on the child.
// Setup the parent template ( =~ DOM Node w/ accessors).
v8::Local<v8::FunctionTemplate> parent = v8::FunctionTemplate::New(isolate);
{
auto signature = v8::Signature::New(isolate, parent);
// cpp accessor as "firstChild":
parent->PrototypeTemplate()->SetAccessorProperty(
v8_str("firstChild"),
v8::FunctionTemplate::New(isolate, CppAccessor, v8::Local<v8::Value>(),
signature));
// JS accessor as "firstChildJS":
auto js_accessor = v8::Local<v8::Function>::Cast(CompileRun(JsAccessor));
parent->PrototypeTemplate()->SetAccessorProperty(v8_str("firstChildJS"),
js_accessor);
}
// Setup child object ( =~ a specific DOM Node, e.g. a <div> ).
// Also, make a creation function on the global object, so we can access it
// in a test.
v8::Local<v8::FunctionTemplate> child = v8::FunctionTemplate::New(isolate);
child->Inherit(parent);
CHECK(env->Global()
->Set(env.local(), v8_str("Node"),
child->GetFunction(env.local()).ToLocalChecked())
.IsJust());
// Setup done: Let's test it:
// The simple case: Run it once.
ExpectInt32("var n = new Node(); n.firstChild", 42);
ExpectInt32("var n = new Node(); n.firstChildJS", 41);
// Run them in a loop. This will likely trigger the optimizing compiler:
ExpectInt32(
"var m = new Node(); "
"var sum = 0; "
"for (var i = 0; i < 3; ++i) { "
" sum += m.firstChild; "
" sum += m.firstChildJS; "
"}; "
"sum;",
3 * (42 + 41));
// Obtain the accessor and call it via apply on the Node:
ExpectInt32(
"var n = new Node(); "
"var g = Object.getOwnPropertyDescriptor("
" n.__proto__.__proto__, 'firstChild')['get']; "
"g.apply(n);",
42);
ExpectInt32(
"var n = new Node(); "
"var g = Object.getOwnPropertyDescriptor("
" n.__proto__.__proto__, 'firstChildJS')['get']; "
"g.apply(n);",
41);
// TODO(vogelheim): Verify compatible receiver check works.
}
#endif // V8_JS_ACCESSORS