Add ES5 Object.freeze and Object.isFrozen methods....

test/mjsunit/object-freeze.js

+// 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
+
+
+// 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) {
+  try {
+    Object.freeze(non_objects[key]);
+    assertUnreachable();
+  } catch(e) {
+    assertTrue(/Object.freeze called on non-object/.test(e));
+  }
+}
+
+for (var key in non_objects) {
+  try {
+    Object.isFrozen(non_objects[key]);
+    assertUnreachable();
+  } catch(e) {
+    assertTrue(/Object.isFrozen called on non-object/.test(e));
+  }
+}
+
+// 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));
+
+try {
+   obj.foo = 42;
+   assertUnreachable();
+} catch(e) {
+  assertTrue(/object is not extensible/.test(e));
+}
+
+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);
+
+try {
+  obj2.foo = 42;
+  assertUnreachable();
+} catch(e) {
+  assertTrue(/object is not extensible/.test(e));
+}
+
+
+// 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));