// 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.preventExtensions method - ES 15.2.3.10 // Flags: --allow-natives-syntax assertFalse(Object.isExtensible()); var obj1 = {}; // Extensible defaults to true. assertTrue(Object.isExtensible(obj1)); Object.preventExtensions(obj1); // Make sure the is_extensible flag is set. assertFalse(Object.isExtensible(obj1)); obj1.x = 42; assertEquals(undefined, obj1.x); // Try adding a new element. obj1[1] = 42; assertEquals(undefined, obj1[1]); // Try when the object has an existing property. var obj2 = {}; assertTrue(Object.isExtensible(obj2)); obj2.x = 42; assertEquals(42, obj2.x); assertTrue(Object.isExtensible(obj2)); Object.preventExtensions(obj2); assertEquals(42, obj2.x); obj2.y = 42; // obj2.y should still be undefined. assertEquals(undefined, obj2.y); // Make sure we can still write values to obj.x. obj2.x = 43; assertEquals(43, obj2.x) obj2.y = new function() { return 42; }; // obj2.y should still be undefined. assertEquals(undefined, obj2.y); assertEquals(43, obj2.x) try { Object.defineProperty(obj2, "y", {value: 42}); } catch (e) { assertTrue(/object is not extensible/.test(e)); } // obj2.y should still be undefined. assertEquals(undefined, obj2.y); assertEquals(43, obj2.x); obj2[1] = 42; assertEquals(undefined, obj2[1]); var arr = new Array(); arr[1] = 10; Object.preventExtensions(arr); arr[2] = 42; assertEquals(10, arr[1]); // We should still be able to change existing elements. arr[1]= 42; assertEquals(42, arr[1]); // Test the the extensible flag is not inherited. var parent = {}; parent.x = 42; Object.preventExtensions(parent); var child = Object.create(parent); // We should be able to add new properties to the child object. child.y = 42; // This should have no influence on the parent class. parent.y = 29; // Test that attributes on functions are also handled correctly. function foo() { return 42; } Object.preventExtensions(foo); foo.x = 29; assertEquals(undefined, foo.x); // when Object.isExtensible(o) === false // assignment should return right hand side value var o = Object.preventExtensions({}); var v = o.v = 50; assertEquals(undefined, o.v); assertEquals(50, v); // test same behavior as above, but for integer properties var n = o[0] = 100; assertEquals(undefined, o[0]); assertEquals(100, n); // Fast properties should remain fast obj = { x: 42, y: 'foo' }; assertTrue(%HasFastProperties(obj)); Object.preventExtensions(obj); assertFalse(Object.isExtensible(obj)); assertFalse(Object.isSealed(obj)); assertTrue(%HasFastProperties(obj)); // Non-extensible objects should share maps where possible obj = { prop1: 1, prop2: 2 }; obj2 = { prop1: 3, prop2: 4 }; assertTrue(%HaveSameMap(obj, obj2)); Object.preventExtensions(obj); Object.preventExtensions(obj2); assertFalse(Object.isExtensible(obj)); assertFalse(Object.isExtensible(obj2)); assertFalse(Object.isSealed(obj)); assertFalse(Object.isSealed(obj2)); assertTrue(%HaveSameMap(obj, obj2)); // Non-extensible 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.preventExtensions(obj); Object.preventExtensions(obj2); assertFalse(Object.isExtensible(obj)); assertFalse(Object.isExtensible(obj2)); assertFalse(Object.isSealed(obj)); assertFalse(Object.isSealed(obj2)); assertTrue(%HaveSameMap(obj, obj2)); // Test packed element array built-in functions with preventExtensions. obj = new Array(undefined, null, 1, -1, 'a', Symbol("test")); assertTrue(%HasPackedElements(obj)); Object.preventExtensions(obj); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); // Verify that the length can't be written by builtins. assertThrows(function() { obj.push(1); }, TypeError); assertDoesNotThrow(function() { obj.shift(); }); assertThrows(function() { obj.unshift(1); }, TypeError); assertThrows(function() { obj.splice(0, 0, 1); }, TypeError); assertDoesNotThrow(function() {obj.splice(0, 0)}); // Verify search, filter, iterator obj = new Array(undefined, null, 1, -1, 'a', Symbol("test")); assertTrue(%HasPackedElements(obj)); Object.preventExtensions(obj); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); assertEquals(obj.lastIndexOf(1), 2); assertEquals(obj.indexOf('a'), 4); assertEquals(obj.indexOf(undefined), 0); assertFalse(obj.includes(Symbol("test"))); assertTrue(obj.includes(undefined)); assertFalse(obj.includes(NaN)); assertTrue(obj.includes()); assertEquals(obj.find(x => x==0), undefined); assertEquals(obj.findIndex(x => x=='a'), 4); assertTrue(obj.some(x => typeof x == 'symbol')); assertFalse(obj.every(x => x == -1)); var filteredArray = obj.filter(e => typeof e == "symbol"); assertEquals(filteredArray.length, 1); assertEquals(obj.map(x => x), obj); var countPositiveNumber = 0; obj.forEach(function(item, index) { if (item === 1) { countPositiveNumber++; assertEquals(index, 2); } }); assertEquals(countPositiveNumber, 1); assertEquals(obj.length, obj.concat([]).length); var iterator = obj.values(); assertEquals(iterator.next().value, undefined); assertEquals(iterator.next().value, null); var iterator = obj.keys(); assertEquals(iterator.next().value, 0); assertEquals(iterator.next().value, 1); var iterator = obj.entries(); assertEquals(iterator.next().value, [0, undefined]); assertEquals(iterator.next().value, [1, null]); // Verify that the value can be written var length = obj.length; for (var i = 0; i < length-1; i++) { obj[i] = 'new'; assertEquals(obj[i], 'new'); } // Verify flat, map, flatMap, join, reduce, reduceRight for non-extensible packed array var arr = ['a', 'b', 'c']; assertTrue(%HasPackedElements(arr)); Object.preventExtensions(arr); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); assertEquals(arr.map(x => [x]), [['a'], ['b'], ['c']]); assertEquals(arr.flatMap(x => [x]), arr); assertEquals(arr.flat(), arr); assertEquals(arr.join('-'), "a-b-c"); const reducer = (accumulator, currentValue) => accumulator + currentValue; assertEquals(arr.reduce(reducer), "abc"); assertEquals(arr.reduceRight(reducer), "cba"); assertEquals(arr.slice(0, 1), ['a']); // Verify change content of non-extensible packed array arr.sort(); assertEquals(arr.join(''), "abc"); arr.reverse(); assertEquals(arr.join(''), "cba"); arr.copyWithin(0, 1, 2); assertEquals(arr.join(''),"bba"); arr.fill('d'); assertEquals(arr.join(''), "ddd"); arr.pop(); assertEquals(arr.join(''), "dd"); // Regression test with simple array var arr = ['a']; Object.preventExtensions(arr); arr[0] = 'b'; assertEquals(arr[0], 'b'); // Test regression Array.concat with double var arr = ['a']; Object.preventExtensions(arr); arr = arr.concat(0.5); assertEquals(arr, ['a', 0.5]); Object.preventExtensions(arr); arr = arr.concat([1.5, 'b']); assertEquals(arr, ['a', 0.5, 1.5, 'b']); // Regression test with change length var arr = ['a', 'b']; Object.preventExtensions(arr); assertEquals(arr.length, 2); arr.length = 3; assertEquals(arr.length, 3); arr[2] = 'c'; assertEquals(arr[2], undefined); arr.length = 1; assertEquals(arr.length, 1); assertEquals(arr[1], undefined); // Test for holey array // Test holey element array built-in functions with preventExtensions. obj = [undefined, null, 1, , -1, 'a', Symbol("test")]; assertTrue(%HasHoleyElements(obj)); Object.preventExtensions(obj); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); // Verify that the length can't be written by builtins. assertThrows(function() { obj.push(1); }, TypeError); assertThrows(function() { obj.shift(); }, TypeError); assertThrows(function() { obj.unshift(1); }, TypeError); assertThrows(function() { obj.splice(0, 0, 1); }, TypeError); assertDoesNotThrow(function() {obj.splice(0, 0)}); // Verify search, filter, iterator obj = [undefined, null, 1, ,-1, 'a', Symbol("test")]; assertTrue(%HasHoleyElements(obj)); Object.preventExtensions(obj); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); assertEquals(obj.lastIndexOf(1), 2); assertEquals(obj.indexOf('a'), 5); assertEquals(obj.indexOf(undefined), 0); assertFalse(obj.includes(Symbol("test"))); assertTrue(obj.includes(undefined)); assertFalse(obj.includes(NaN)); assertTrue(obj.includes()); assertEquals(obj.find(x => x==0), undefined); assertEquals(obj.findIndex(x => x=='a'), 5); assertTrue(obj.some(x => typeof x == 'symbol')); assertFalse(obj.every(x => x == -1)); var filteredArray = obj.filter(e => typeof e == "symbol"); assertEquals(filteredArray.length, 1); assertEquals(obj.map(x => x), obj); var countPositiveNumber = 0; obj.forEach(function(item, index) { if (item === 1) { countPositiveNumber++; assertEquals(index, 2); } }); assertEquals(countPositiveNumber, 1); assertEquals(obj.length, obj.concat([]).length); var iterator = obj.values(); assertEquals(iterator.next().value, undefined); assertEquals(iterator.next().value, null); var iterator = obj.keys(); assertEquals(iterator.next().value, 0); assertEquals(iterator.next().value, 1); var iterator = obj.entries(); assertEquals(iterator.next().value, [0, undefined]); assertEquals(iterator.next().value, [1, null]); // Verify that the value can be written var length = obj.length; for (var i = 0; i < length-1; i++) { if (i==3) continue; obj[i] = 'new'; assertEquals(obj[i], 'new'); } // Verify flat, map, flatMap, join, reduce, reduceRight for non-extensible holey array var arr = [, 'a', 'b', 'c']; assertTrue(%HasHoleyElements(arr)); Object.preventExtensions(arr); assertFalse(Object.isSealed(obj)); assertFalse(Object.isFrozen(obj)); assertFalse(Object.isExtensible(obj)); assertTrue(Array.isArray(obj)); assertEquals(arr.map(x => [x]), [, ['a'], ['b'], ['c']]); assertEquals(arr.flatMap(x => [x]), ["a", "b", "c"]); assertEquals(arr.flat(), ["a", "b", "c"]); assertEquals(arr.join('-'), "-a-b-c"); const reducer1 = (accumulator, currentValue) => accumulator + currentValue; assertEquals(arr.reduce(reducer1), "abc"); assertEquals(arr.reduceRight(reducer1), "cba"); assertEquals(arr.slice(0, 1), [,]); assertEquals(arr.slice(1, 2), ["a"]); // Verify change content of non-extensible holey array assertThrows(function(){arr.sort();}, TypeError); assertEquals(arr.join(''), "abc"); assertThrows(function(){arr.reverse();}, TypeError); assertEquals(arr.join(''), "abc"); assertThrows(function(){arr.copyWithin(0, 1, 2);}, TypeError); arr.copyWithin(1, 2, 3); assertEquals(arr.join(''),"bbc"); assertThrows(function(){arr.fill('d');}, TypeError); assertEquals(arr.join(''), "bbc"); arr.pop(); assertEquals(arr.join(''), "bb"); // Regression test with simple holey array var arr = [, 'a']; Object.preventExtensions(arr); arr[1] = 'b'; assertEquals(arr[1], 'b'); arr[0] = 1; assertEquals(arr[0], undefined); // Test regression Array.concat with double var arr = ['a', , 'b']; Object.preventExtensions(arr); arr = arr.concat(0.5); assertEquals(arr, ['a', ,'b', 0.5]); Object.preventExtensions(arr); arr = arr.concat([1.5, 'c']); assertEquals(arr, ['a', ,'b', 0.5, 1.5, 'c']); // Regression test with change length var arr = ['a', , 'b']; Object.preventExtensions(arr); assertEquals(arr.length, 3); arr.length = 4; assertEquals(arr.length, 4); arr[3] = 'c'; assertEquals(arr[3], undefined); arr.length = 2; assertEquals(arr.length, 2); assertEquals(arr[2], undefined); assertEquals(arr.pop(), undefined); assertEquals(arr.length, 1); assertEquals(arr[1], undefined); // Change length with holey entries at the end var arr = ['a', ,]; Object.preventExtensions(arr); assertEquals(arr.length, 2); arr.length = 0; assertEquals(arr.length, 0); arr.length = 3; assertEquals(arr.length, 3); arr.length = 0; assertEquals(arr.length, 0); // Spread with array var arr = ['a', 'b', 'c']; Object.preventExtensions(arr); var arrSpread = [...arr]; assertEquals(arrSpread.length, arr.length); assertEquals(arrSpread[0], 'a'); assertEquals(arrSpread[1], 'b'); assertEquals(arrSpread[2], 'c'); // Spread with array-like function returnArgs() { return Object.preventExtensions(arguments); } var arrLike = returnArgs('a', 'b', 'c'); assertFalse(Object.isExtensible(arrLike)); var arrSpread = [...arrLike]; assertEquals(arrSpread.length, arrLike.length); assertEquals(arrSpread[0], 'a'); assertEquals(arrSpread[1], 'b'); assertEquals(arrSpread[2], 'c'); // Spread with holey function countArgs() { return arguments.length; } var arr = [, 'b','c']; Object.preventExtensions(arr); assertEquals(countArgs(...arr), 3); assertEquals(countArgs(...[...arr]), 3); assertEquals(countArgs.apply(this, [...arr]), 3); function checkUndefined() { return arguments[0] === undefined; } assertTrue(checkUndefined(...arr)); assertTrue(checkUndefined(...[...arr])); assertTrue(checkUndefined.apply(this, [...arr])); // // Array.prototype.map // (function() { var a = Object.preventExtensions(['0','1','2','3','4']); // Simple use. var result = [1,2,3,4,5]; assertArrayEquals(result, a.map(function(n) { return Number(n) + 1; })); // Use specified object as this object when calling the function. var o = { delta: 42 } result = [42,43,44,45,46]; assertArrayEquals(result, a.map(function(n) { return this.delta + Number(n); }, o)); // Modify original array. b = Object.preventExtensions(['0','1','2','3','4']); result = [1,2,3,4,5]; assertArrayEquals(result, b.map(function(n, index, array) { array[index] = Number(n) + 1; return Number(n) + 1; })); assertArrayEquals(b, result); // Only loop through initial part of array and elements are not // added. a = Object.preventExtensions(['0','1','2','3','4']); result = [1,2,3,4,5]; assertArrayEquals(result, a.map(function(n, index, array) { assertThrows(() => { array.push(n) }); return Number(n) + 1; })); assertArrayEquals(['0','1','2','3','4'], a); // Respect holes. a = new Array(20); a[1] = '2'; Object.preventExtensions(a); a = Object.preventExtensions(a).map(function(n) { return 2*Number(n); }); for (var i in a) { assertEquals(4, a[i]); assertEquals('1', i); } // Skip over missing properties. a = { "0": 1, "2": 2, length: 3 }; var received = []; assertArrayEquals([2, , 4], Array.prototype.map.call(Object.preventExtensions(a), function(n) { received.push(n); return n * 2; })); assertArrayEquals([1, 2], received); // Modify array prototype a = ['1', , 2]; received = []; assertThrows(() => { Array.prototype.map.call(Object.preventExtensions(a), function(n) { a.__proto__ = null; received.push(n); return n * 2; }); }, TypeError); assertArrayEquals([], received); // Create a new object in each function call when receiver is a // primitive value. See ECMA-262, Annex C. a = []; Object.preventExtensions(['1', '2']).map(function() { a.push(this) }, ""); assertTrue(a[0] !== a[1]); // Do not create a new object otherwise. a = []; Object.preventExtensions(['1', '2']).map(function() { a.push(this) }, {}); assertSame(a[0], a[1]); // In strict mode primitive values should not be coerced to an object. a = []; Object.preventExtensions(['1', '2']).map(function() { 'use strict'; a.push(this); }, ""); assertEquals("", a[0]); assertEquals(a[0], a[1]); })();