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
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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 slicing array of holes keeps it as array of holes
29(function() {
30  var array = new Array(10);
31  for (var i = 0; i < 7; i++) {
32    var sliced = array.slice();
33    assertEquals(array.length, sliced.length);
34    assertFalse(0 in sliced);
35  }
36})();
37
38
39// Check various variants of empty array's slicing.
40(function() {
41  for (var i = 0; i < 7; i++) {
42    assertEquals([], [].slice(0, 0));
43    assertEquals([], [].slice(1, 0));
44    assertEquals([], [].slice(0, 1));
45    assertEquals([], [].slice(-1, 0));
46  }
47})();
48
49
50// Check various forms of arguments omission.
51(function() {
52  var array = new Array(7);
53
54  for (var i = 0; i < 7; i++) {
55    assertEquals(array, array.slice());
56    assertEquals(array, array.slice(0));
57    assertEquals(array, array.slice(undefined));
58    assertEquals(array, array.slice("foobar"));
59    assertEquals(array, array.slice(undefined, undefined));
60  }
61})();
62
63
64// Check variants of negatives and positive indices.
65(function() {
66  var array = new Array(7);
67
68  for (var i = 0; i < 7; i++) {
69    assertEquals(7, array.slice(-100).length);
70    assertEquals(3, array.slice(-3).length);
71    assertEquals(3, array.slice(4).length);
72    assertEquals(1, array.slice(6).length);
73    assertEquals(0, array.slice(7).length);
74    assertEquals(0, array.slice(8).length);
75    assertEquals(0, array.slice(100).length);
76
77    assertEquals(0, array.slice(0, -100).length);
78    assertEquals(4, array.slice(0, -3).length);
79    assertEquals(4, array.slice(0, 4).length);
80    assertEquals(6, array.slice(0, 6).length);
81    assertEquals(7, array.slice(0, 7).length);
82    assertEquals(7, array.slice(0, 8).length);
83    assertEquals(7, array.slice(0, 100).length);
84
85    // Some exotic cases.
86
87    obj = { toString: function() { throw 'Exception'; } };
88
89    // More than 2 arguments:
90    assertEquals(7, array.slice(0, 7, obj, null, undefined).length);
91
92    // Custom conversion:
93    assertEquals(1, array.slice({valueOf: function() { return 1; }},
94                                {toString: function() { return 2; }}).length);
95
96    // Throwing an exception in conversion:
97    try {
98      assertEquals(7, array.slice(0, obj).length);
99      throw 'Should have thrown';
100    } catch (e) {
101      assertEquals('Exception', e);
102    }
103  }
104})();
105
106
107// Nasty: modify the array in ToInteger.
108(function() {
109  var array = [];
110  var expected = []
111  bad_guy = { valueOf: function() { array.push(array.length); return -1; } };
112
113  for (var i = 0; i < 13; i++) {
114    var sliced = array.slice(bad_guy);
115    expected.push(i);
116    assertEquals(expected, array);
117    // According to the spec (15.4.4.10), length is calculated before
118    // performing ToInteger on arguments.
119    if (i == 0) {
120      assertEquals([], sliced);  // Length was 0, nothing to get.
121    } else {
122      // Actually out of array [0..i] we get [i - 1] as length is i.
123      assertEquals([i - 1], sliced);
124    }
125  }
126})();
127
128
129// Now check the case with array of holes and some elements on prototype.
130// Note: that is important that this test runs before the next one
131// as the next one tampers Array.prototype.
132(function() {
133  var len = 9;
134  var array = new Array(len);
135
136  var at3 = "@3";
137  var at7 = "@7";
138
139  for (var i = 0; i < 7; i++) {
140    var array_proto = [];
141    array_proto[3] = at3;
142    array_proto[7] = at7;
143    array.__proto__ = array_proto;
144
145    assertEquals(len, array.length);
146    for (var i = 0; i < array.length; i++) {
147      assertEquals(array[i], array_proto[i]);
148    }
149
150    var sliced = array.slice();
151
152    assertEquals(len, sliced.length);
153
154    assertTrue(delete array_proto[3]);
155    assertTrue(delete array_proto[7]);
156
157    // Note that slice copies values from prototype into the array.
158    assertEquals(array[3], undefined);
159    assertFalse(array.hasOwnProperty(3));
160    assertEquals(sliced[3], at3);
161    assertTrue(sliced.hasOwnProperty(3));
162
163    assertEquals(array[7], undefined);
164    assertFalse(array.hasOwnProperty(7));
165    assertEquals(sliced[7], at7);
166    assertTrue(sliced.hasOwnProperty(7));
167
168    // ... but keeps the rest as holes:
169    array_proto[5] = "@5";
170    assertEquals(array[5], array_proto[5]);
171    assertFalse(array.hasOwnProperty(5));
172  }
173})();
174
175
176// Now check the case with array of holes and some elements on prototype.
177(function() {
178  var len = 9;
179  var array = new Array(len);
180
181  var at3 = "@3";
182  var at7 = "@7";
183
184  for (var i = 0; i < 7; i++) {
185    Array.prototype[3] = at3;
186    Array.prototype[7] = at7;
187
188    assertEquals(len, array.length);
189    for (var i = 0; i < array.length; i++) {
190      assertEquals(array[i], Array.prototype[i]);
191    }
192
193    var sliced = array.slice();
194
195    assertEquals(len, sliced.length);
196
197    assertTrue(delete Array.prototype[3]);
198    assertTrue(delete Array.prototype[7]);
199
200    // Note that slice copies values from prototype into the array.
201    assertEquals(array[3], undefined);
202    assertFalse(array.hasOwnProperty(3));
203    assertEquals(sliced[3], at3);
204    assertTrue(sliced.hasOwnProperty(3));
205
206    assertEquals(array[7], undefined);
207    assertFalse(array.hasOwnProperty(7));
208    assertEquals(sliced[7], at7);
209    assertTrue(sliced.hasOwnProperty(7));
210
211    // ... but keeps the rest as holes:
212    Array.prototype[5] = "@5";
213    assertEquals(array[5], Array.prototype[5]);
214    assertFalse(array.hasOwnProperty(5));
215    assertEquals(sliced[5], Array.prototype[5]);
216    assertFalse(sliced.hasOwnProperty(5));
217
218    assertTrue(delete Array.prototype[5]);
219  }
220})();
221
222// Check slicing on arguments object.
223(function() {
224  function func(expected, a0, a1, a2) {
225    assertEquals(expected, Array.prototype.slice.call(arguments, 1));
226  }
227
228  func([]);
229  func(['a'], 'a');
230  func(['a', 1], 'a', 1);
231  func(['a', 1, undefined], 'a', 1, undefined);
232  func(['a', 1, undefined, void(0)], 'a', 1, undefined, void(0));
233})();
234
235// Check slicing on arguments object when missing arguments get assigined.
236(function() {
237  function func(x, y) {
238    assertEquals(1, arguments.length);
239    assertEquals(undefined, y);
240    y = 239;
241    assertEquals(1, arguments.length);  // arguments length is the same.
242    assertEquals([x], Array.prototype.slice.call(arguments, 0));
243  }
244
245  func('a');
246})();
247
248// Check slicing on arguments object when length property has been set.
249(function() {
250  function func(x, y) {
251    assertEquals(1, arguments.length);
252    arguments.length = 7;
253    assertEquals([x,,,,,,,], Array.prototype.slice.call(arguments, 0));
254  }
255
256  func('a');
257})();
258
259// Check slicing on arguments object when length property has been set to
260// some strange value.
261(function() {
262  function func(x, y) {
263    assertEquals(1, arguments.length);
264    arguments.length = 'foobar';
265    assertEquals([], Array.prototype.slice.call(arguments, 0));
266  }
267
268  func('a');
269})();
270
271// Check slicing on arguments object when extra argument has been added
272// via indexed assignment.
273(function() {
274  function func(x, y) {
275    assertEquals(1, arguments.length);
276    arguments[3] = 239;
277    assertEquals([x], Array.prototype.slice.call(arguments, 0));
278  }
279
280  func('a');
281})();
282
283// Check slicing on arguments object when argument has been deleted by index.
284(function() {
285  function func(x, y, z) {
286    assertEquals(3, arguments.length);
287    delete arguments[1];
288    assertEquals([x,,z], Array.prototype.slice.call(arguments, 0));
289  }
290
291  func('a', 'b', 'c');
292})();
293