delete.js 5.81 KB
Newer Older
1
// Copyright 2008 the V8 project authors. All rights reserved.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158
// 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.

// We use the has() function to avoid relying on a functioning
// implementation of 'in'.
function has(o, k) { return typeof o[k] !== 'undefined'; }

assertTrue(delete null);
assertTrue(delete 2);
assertTrue(delete 'foo');
assertTrue(delete Number(7));
assertTrue(delete new Number(8));

assertTrue(delete {}.x);
assertTrue(delete {}.y);
assertTrue(delete {}.toString);

x = 42;
assertEquals(42, x);
assertTrue(delete x);
assertTrue(typeof x === 'undefined', "x is gone");

var y = 87; // should have DontDelete attribute
assertEquals(87, y);
assertFalse(delete y, "don't delete");
assertFalse(typeof y === 'undefined');
assertEquals(87, y);

var o = { x: 42, y: 87 };
assertTrue(has(o, 'x'));
assertTrue(has(o, 'y'));
assertTrue(delete o.x);
assertFalse(has(o, 'x'));
assertTrue(has(o, 'y'));
assertTrue(delete o['y']);
assertFalse(has(o, 'x'));
assertFalse(has(o, 'y'));


var o = {};
for (var i = 0x0020; i < 0x02ff; i+=2) {
  o[String.fromCharCode(i)] = i;
  o[String.fromCharCode(i+1)] = i+1;
}
for (var i = 0x0020; i < 0x02ff; i+=2) {
  assertTrue(delete o[String.fromCharCode(i)]);
}
for (var i = 0x0020; i < 0x02ff; i+=2) {
  assertFalse(has(o, String.fromCharCode(i)), "deleted (" + i + ")");
  assertTrue(has(o, String.fromCharCode(i+1)), "still here (" + i + ")");
}


var a = [0,1,2];
assertTrue(has(a, 0));
assertTrue(delete a[0]);
assertFalse(has(a, 0), "delete 0");
assertEquals(1, a[1]);
assertEquals(2, a[2]);
assertTrue(delete a[100], "delete 100");
assertTrue(delete a[Math.pow(2,31)-1], "delete 2^31-1");
assertFalse(has(a, 0), "delete 0");
assertEquals(1, a[1]);
assertEquals(2, a[2]);


var a = [0,1,2];
assertEquals(3, a.length);
assertTrue(delete a[2]);
assertEquals(3, a.length);
assertTrue(delete a[0]);
assertEquals(3, a.length);
assertTrue(delete a[1]);
assertEquals(3, a.length);


var o = {};
o[Math.pow(2,30)-1] = 0;
o[Math.pow(2,31)-1] = 0;
o[1] = 0;
assertTrue(delete o[0]);
assertTrue(delete o[Math.pow(2,30)]);
assertFalse(has(o, 0), "delete 0");
assertFalse(has(o, Math.pow(2,30)));
assertTrue(has(o, 1));
assertTrue(has(o, Math.pow(2,30)-1));
assertTrue(has(o, Math.pow(2,31)-1));

assertTrue(delete o[Math.pow(2,30)-1]);
assertTrue(has(o, 1));
assertFalse(has(o, Math.pow(2,30)-1), "delete 2^30-1");
assertTrue(has(o, Math.pow(2,31)-1));

assertTrue(delete o[1]);
assertFalse(has(o, 1), "delete 1");
assertFalse(has(o, Math.pow(2,30)-1), "delete 2^30-1");
assertTrue(has(o, Math.pow(2,31)-1));

assertTrue(delete o[Math.pow(2,31)-1]);
assertFalse(has(o, 1), "delete 1");
assertFalse(has(o, Math.pow(2,30)-1), "delete 2^30-1");
assertFalse(has(o, Math.pow(2,31)-1), "delete 2^31-1");


var a = [];
a[Math.pow(2,30)-1] = 0;
a[Math.pow(2,31)-1] = 0;
a[1] = 0;
assertTrue(delete a[0]);
assertTrue(delete a[Math.pow(2,30)]);
assertFalse(has(a, 0), "delete 0");
assertFalse(has(a, Math.pow(2,30)), "delete 2^30");
assertTrue(has(a, 1));
assertTrue(has(a, Math.pow(2,30)-1));
assertTrue(has(a, Math.pow(2,31)-1));
assertEquals(Math.pow(2,31), a.length);

assertTrue(delete a[Math.pow(2,30)-1]);
assertTrue(has(a, 1));
assertFalse(has(a, Math.pow(2,30)-1), "delete 2^30-1");
assertTrue(has(a, Math.pow(2,31)-1));
assertEquals(Math.pow(2,31), a.length);

assertTrue(delete a[1]);
assertFalse(has(a, 1), "delete 1");
assertFalse(has(a, Math.pow(2,30)-1), "delete 2^30-1");
assertTrue(has(a, Math.pow(2,31)-1));
assertEquals(Math.pow(2,31), a.length);

assertTrue(delete a[Math.pow(2,31)-1]);
assertFalse(has(a, 1), "delete 1");
assertFalse(has(a, Math.pow(2,30)-1), "delete 2^30-1");
assertFalse(has(a, Math.pow(2,31)-1), "delete 2^31-1");
assertEquals(Math.pow(2,31), a.length);
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180

// Check that a LoadIC for a dictionary field works, even
// when the dictionary probe misses.
function load_deleted_property_using_IC() {
  var x = new Object();
  x.a = 3;
  x.b = 4;
  x.c = 5;

  delete x.c;
  assertEquals(3, load_a(x));
  assertEquals(3, load_a(x));
  delete x.a;
  assertTrue(typeof load_a(x) === 'undefined', "x.a is gone");
  assertTrue(typeof load_a(x) === 'undefined', "x.a is gone");
}

function load_a(x) {
  return x.a;
}

load_deleted_property_using_IC();
181 182 183 184 185 186 187 188 189 190 191 192 193 194


(function deleteLargeDoubleArrayAtEnd() {
  var o = {};
  var max = 100000;
  for (var i = 0; i <= max; i++) {
    o[i] = 1.1;
  }
  delete o[max];
  for (var i = 0; i < max; i++) {
    assertEquals(1.1, o[i]);
  }
  assertEquals(undefined, o[max]);
})();