1 // Copyright 2010 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 // Check that shifting array of holes keeps it as array of holes 29 (function() { 30 var array = new Array(10); 31 array.shift(); 32 assertFalse(0 in array); 33 })(); 34 35 // Now check the case with array of holes and some elements on prototype. 36 (function() { 37 var len = 9; 38 var array = new Array(len); 39 Array.prototype[3] = "@3"; 40 Array.prototype[7] = "@7"; 41 42 assertEquals(len, array.length); 43 for (var i = 0; i < array.length; i++) { 44 assertEquals(array[i], Array.prototype[i]); 45 } 46 47 array.shift(); 48 49 assertEquals(len - 1, array.length); 50 // Note that shift copies values from prototype into the array. 51 assertEquals(array[2], Array.prototype[3]); 52 assertTrue(array.hasOwnProperty(2)); 53 54 assertEquals(array[6], Array.prototype[7]); 55 assertTrue(array.hasOwnProperty(6)); 56 57 // ... but keeps the rest as holes: 58 Array.prototype[5] = "@5"; 59 assertEquals(array[5], Array.prototype[5]); 60 assertFalse(array.hasOwnProperty(5)); 61 62 assertEquals(array[3], Array.prototype[3]); 63 assertFalse(array.hasOwnProperty(3)); 64 65 assertEquals(array[7], Array.prototype[7]); 66 assertFalse(array.hasOwnProperty(7)); 67 68 assertTrue(delete Array.prototype[3]); 69 assertTrue(delete Array.prototype[5]); 70 assertTrue(delete Array.prototype[7]); 71 })(); 72 73 // Now check the case with array of holes and some elements on prototype 74 // which is an array itself. 75 (function() { 76 var len = 9; 77 var array = new Array(len); 78 var array_proto = new Array(); 79 array_proto[3] = "@3"; 80 array_proto[7] = "@7"; 81 array.__proto__ = array_proto; 82 83 assertEquals(len, array.length); 84 for (var i = 0; i < array.length; i++) { 85 assertEquals(array[i], array_proto[i]); 86 } 87 88 array.shift(); 89 90 assertEquals(len - 1, array.length); 91 // Note that shift copies values from prototype into the array. 92 assertEquals(array[2], array_proto[3]); 93 assertTrue(array.hasOwnProperty(2)); 94 95 assertEquals(array[6], array_proto[7]); 96 assertTrue(array.hasOwnProperty(6)); 97 98 // ... but keeps the rest as holes: 99 array_proto[5] = "@5"; 100 assertEquals(array[5], array_proto[5]); 101 assertFalse(array.hasOwnProperty(5)); 102 103 assertEquals(array[3], array_proto[3]); 104 assertFalse(array.hasOwnProperty(3)); 105 106 assertEquals(array[7], array_proto[7]); 107 assertFalse(array.hasOwnProperty(7)); 108 })(); 109