v8/test/mjsunit/object-freeze.js
verwaest@chromium.org 36e91242fd Make Object.freeze fast
This patch both speeds up the freeze operation itself, but also
allows properties to remain in fast mode. Objects with non-empty
elements backing stores still end up with slow elements.

Relanding r14758 and r14759 with fix for Test262: only mark properties
and elements READ_ONLY if they are not JS setter/getters. Tightened up
tests to assert frozen-ness, and added targeted tests for the new code
(covering accessors).

BUG=v8:1858, 115960
R=verwaest@chromium.org

Review URL: https://chromiumcodereview.appspot.com/15691007

Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14762 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2013-05-23 07:05:58 +00:00

299 lines
9.1 KiB
JavaScript

// Copyright 2010 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
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Tests the Object.freeze and Object.isFrozen methods - ES 15.2.3.9 and
// ES 15.2.3.12
// Flags: --allow-natives-syntax
// Test that we throw an error if an object is not passed as argument.
var non_objects = new Array(undefined, null, 1, -1, 0, 42.43);
for (var key in non_objects) {
var exception = false;
try {
Object.freeze(non_objects[key]);
} catch(e) {
exception = true;
assertTrue(/Object.freeze called on non-object/.test(e));
}
assertTrue(exception);
}
for (var key in non_objects) {
exception = false;
try {
Object.isFrozen(non_objects[key]);
} catch(e) {
exception = true;
assertTrue(/Object.isFrozen called on non-object/.test(e));
}
assertTrue(exception);
}
// Test normal data properties.
var obj = { x: 42, z: 'foobar' };
var desc = Object.getOwnPropertyDescriptor(obj, 'x');
assertTrue(desc.writable);
assertTrue(desc.configurable);
assertEquals(42, desc.value);
desc = Object.getOwnPropertyDescriptor(obj, 'z');
assertTrue(desc.writable);
assertTrue(desc.configurable);
assertEquals('foobar', desc.value);
assertTrue(Object.isExtensible(obj));
assertFalse(Object.isFrozen(obj));
Object.freeze(obj);
// Make sure we are no longer extensible.
assertFalse(Object.isExtensible(obj));
assertTrue(Object.isFrozen(obj));
obj.foo = 42;
assertEquals(obj.foo, undefined);
desc = Object.getOwnPropertyDescriptor(obj, 'x');
assertFalse(desc.writable);
assertFalse(desc.configurable);
assertEquals(42, desc.value);
desc = Object.getOwnPropertyDescriptor(obj, 'z');
assertFalse(desc.writable);
assertFalse(desc.configurable);
assertEquals("foobar", desc.value);
// Make sure that even if we try overwrite a value that is not writable, it is
// not changed.
obj.x = "tete";
assertEquals(42, obj.x);
obj.x = { get: function() {return 43}, set: function() {} };
assertEquals(42, obj.x);
// Test on accessors.
var obj2 = {};
function get() { return 43; };
function set() {};
Object.defineProperty(obj2, 'x', { get: get, set: set, configurable: true });
desc = Object.getOwnPropertyDescriptor(obj2, 'x');
assertTrue(desc.configurable);
assertEquals(undefined, desc.value);
assertEquals(set, desc.set);
assertEquals(get, desc.get);
assertTrue(Object.isExtensible(obj2));
assertFalse(Object.isFrozen(obj2));
Object.freeze(obj2);
assertTrue(Object.isFrozen(obj2));
assertFalse(Object.isExtensible(obj2));
desc = Object.getOwnPropertyDescriptor(obj2, 'x');
assertFalse(desc.configurable);
assertEquals(undefined, desc.value);
assertEquals(set, desc.set);
assertEquals(get, desc.get);
obj2.foo = 42;
assertEquals(obj2.foo, undefined);
// Test freeze on arrays.
var arr = new Array(42,43);
desc = Object.getOwnPropertyDescriptor(arr, '0');
assertTrue(desc.configurable);
assertTrue(desc.writable);
assertEquals(42, desc.value);
desc = Object.getOwnPropertyDescriptor(arr, '1');
assertTrue(desc.configurable);
assertTrue(desc.writable);
assertEquals(43, desc.value);
assertTrue(Object.isExtensible(arr));
assertFalse(Object.isFrozen(arr));
Object.freeze(arr);
assertTrue(Object.isFrozen(arr));
assertFalse(Object.isExtensible(arr));
desc = Object.getOwnPropertyDescriptor(arr, '0');
assertFalse(desc.configurable);
assertFalse(desc.writable);
assertEquals(42, desc.value);
desc = Object.getOwnPropertyDescriptor(arr, '1');
assertFalse(desc.configurable);
assertFalse(desc.writable);
assertEquals(43, desc.value);
arr[0] = 'foo';
assertEquals(arr[0], 42);
// Test that isFrozen return the correct value even if configurable has been set
// to false on all properties manually and the extensible flag has also been set
// to false manually.
var obj3 = { x: 42, y: 'foo' };
assertFalse(Object.isFrozen(obj3));
Object.defineProperty(obj3, 'x', {configurable: false, writable: false});
Object.defineProperty(obj3, 'y', {configurable: false, writable: false});
Object.preventExtensions(obj3);
assertTrue(Object.isFrozen(obj3));
// Make sure that an object that has only non-configurable, but one
// writable property, is not classified as frozen.
var obj4 = {};
Object.defineProperty(obj4, 'x', {configurable: false, writable: true});
Object.defineProperty(obj4, 'y', {configurable: false, writable: false});
Object.preventExtensions(obj4);
assertFalse(Object.isFrozen(obj4));
// Make sure that an object that has only non-writable, but one
// configurable property, is not classified as frozen.
var obj5 = {};
Object.defineProperty(obj5, 'x', {configurable: true, writable: false});
Object.defineProperty(obj5, 'y', {configurable: false, writable: false});
Object.preventExtensions(obj5);
assertFalse(Object.isFrozen(obj5));
// Make sure that Object.freeze returns the frozen object.
var obj6 = {}
assertTrue(obj6 === Object.freeze(obj6))
// Test that the enumerable attribute is unperturbed by freezing.
obj = { x: 42, y: 'foo' };
Object.defineProperty(obj, 'y', {enumerable: false});
Object.freeze(obj);
assertTrue(Object.isFrozen(obj));
desc = Object.getOwnPropertyDescriptor(obj, 'x');
assertTrue(desc.enumerable);
desc = Object.getOwnPropertyDescriptor(obj, 'y');
assertFalse(desc.enumerable);
// Fast properties should remain fast
obj = { x: 42, y: 'foo' };
assertTrue(%HasFastProperties(obj));
Object.freeze(obj);
assertTrue(Object.isFrozen(obj));
assertTrue(%HasFastProperties(obj));
// Frozen objects should share maps where possible
obj = { prop1: 1, prop2: 2 };
obj2 = { prop1: 3, prop2: 4 };
assertTrue(%HaveSameMap(obj, obj2));
Object.freeze(obj);
Object.freeze(obj2);
assertTrue(Object.isFrozen(obj));
assertTrue(Object.isFrozen(obj2));
assertTrue(%HaveSameMap(obj, obj2));
// Frozen objects should share maps even when they have elements
obj = { prop1: 1, prop2: 2, 75: 'foo' };
obj2 = { prop1: 3, prop2: 4, 150: 'bar' };
assertTrue(%HaveSameMap(obj, obj2));
Object.freeze(obj);
Object.freeze(obj2);
assertTrue(Object.isFrozen(obj));
assertTrue(Object.isFrozen(obj2));
assertTrue(%HaveSameMap(obj, obj2));
// Setting elements after freezing should not be allowed
obj = { prop: 'thing' };
Object.freeze(obj);
assertTrue(Object.isFrozen(obj));
obj[0] = 'hello';
assertFalse(obj.hasOwnProperty(0));
// Freezing an object in dictionary mode should work
// Also testing that getter/setter properties work after freezing
obj = { };
for (var i = 0; i < 100; ++i) {
obj['x' + i] = i;
}
var accessorDidRun = false;
Object.defineProperty(obj, 'accessor', {
get: function() { return 42 },
set: function() { accessorDidRun = true },
configurable: true,
enumerable: true
});
assertFalse(%HasFastProperties(obj));
Object.freeze(obj);
assertFalse(%HasFastProperties(obj));
assertTrue(Object.isFrozen(obj));
assertFalse(Object.isExtensible(obj));
for (var i = 0; i < 100; ++i) {
desc = Object.getOwnPropertyDescriptor(obj, 'x' + i);
assertFalse(desc.writable);
assertFalse(desc.configurable);
}
assertEquals(42, obj.accessor);
assertFalse(accessorDidRun);
obj.accessor = 'ignored value';
assertTrue(accessorDidRun);
// Freezing arguments should work
var func = function(arg) {
Object.freeze(arguments);
assertTrue(Object.isFrozen(arguments));
};
func('hello', 'world');
func('goodbye', 'world');
// Freezing sparse arrays
var sparseArr = [0, 1];
sparseArr[10000] = 10000;
Object.freeze(sparseArr);
assertTrue(Object.isFrozen(sparseArr));
// Accessors on fast object should behavior properly after freezing
obj = {};
Object.defineProperty(obj, 'accessor', {
get: function() { return 42 },
set: function() { accessorDidRun = true },
configurable: true,
enumerable: true
});
assertTrue(%HasFastProperties(obj));
Object.freeze(obj);
assertTrue(Object.isFrozen(obj));
assertTrue(%HasFastProperties(obj));
assertEquals(42, obj.accessor);
accessorDidRun = false;
obj.accessor = 'ignored value';
assertTrue(accessorDidRun);