1// Copyright 2008 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/**
29 * This test uses assert{True,False}(... == ...) instead of
30 * assertEquals(..., ...) to not rely on the details of the
31 * implementation of assertEquals.
32 */
33
34function testEqual(a, b) {
35  assertTrue(a == b);
36  assertTrue(b == a);
37  assertFalse(a != b);
38  assertFalse(b != a);
39}
40
41function testNotEqual(a, b) {
42  assertFalse(a == b);
43  assertFalse(b == a);
44  assertTrue(a != b);
45  assertTrue(b != a);
46}
47
48// Object where ToPrimitive returns value.
49function Wrapper(value) {
50  this.value = value;
51  this.valueOf = function () { return this.value; };
52}
53
54// Object where ToPrimitive returns value by failover to toString when
55// valueOf isn't a function.
56function Wrapper2(value) {
57  this.value = value;
58  this.valueOf = null;
59  this.toString = function () { return this.value; };
60}
61
62
63// Compare values of same type.
64
65// Numbers are equal if same, unless NaN, which isn't equal to anything, and
66// +/-0 being equal.
67
68testNotEqual(NaN, NaN);
69testNotEqual(NaN, 0);
70testNotEqual(NaN, Infinity);
71
72testEqual(Number.MAX_VALUE, Number.MAX_VALUE);
73testEqual(Number.MIN_VALUE, Number.MIN_VALUE);
74testEqual(Infinity, Infinity);
75testEqual(-Infinity, -Infinity);
76
77testEqual(0, 0);
78testEqual(0, -0);
79testEqual(-0, -0);
80
81testNotEqual(0.9, 1);
82testNotEqual(0.999999, 1);
83testNotEqual(0.9999999999, 1);
84testNotEqual(0.9999999999999, 1);
85
86// Strings are equal if containing the same code points.
87
88testEqual('hello', 'hello');
89testEqual('hello', 'hel' + 'lo');
90testEqual('', '');
91testEqual('\u0020\x20', '  ');  // Escapes are not part of the value.
92
93// Booleans are equal if they are the same.
94
95testEqual(true, true);
96testEqual(false, false);
97testNotEqual(true, false);
98
99// Null and undefined are equal to themselves.
100
101testEqual(null, null);
102testEqual(undefined, undefined);
103
104// Objects are equal if they are the same object only.
105
106testEqual(Math, Math);
107testEqual(Object.prototype, Object.prototype);
108
109
110(function () {
111  var x = new Wrapper(null);
112  var y = x, z = x;
113   testEqual(y, x);
114})();
115
116(function () {
117  var x = new Boolean(true);
118  var y = x, z = x;
119   testEqual(y, x);
120})();
121
122(function () {
123  var x = new Boolean(false);
124  var y = x, z = x;
125   testEqual(y, x);
126})();
127
128// Test comparing values of different types.
129
130// Null and undefined are equal to each-other, and to nothing else.
131testEqual(null, undefined);
132testEqual(undefined, null);
133
134testNotEqual(null, new Wrapper(null));
135testNotEqual(null, 0);
136testNotEqual(null, false);
137testNotEqual(null, "");
138testNotEqual(null, new Object());
139testNotEqual(undefined, new Wrapper(undefined));
140testNotEqual(undefined, 0);
141testNotEqual(undefined, false);
142testNotEqual(undefined, "");
143testNotEqual(undefined, new Object());
144
145// Numbers compared to Strings will convert the string to a number using
146// the internal ToNumber conversion.
147
148testEqual(1, '1');
149testEqual(255, '0xff');
150testEqual(0, '\r');  // ToNumber ignores tailing and trailing whitespace.
151testEqual(1e19, '1e19');
152testEqual(Infinity, "Infinity");
153
154// Booleans compared to anything else will be converted to numbers.
155testEqual(false, 0);
156testEqual(true, 1);
157testEqual(false, "0");  // String also converted to number.
158testEqual(true, "1");
159
160// Objects compared to Number or String (or Boolean, since that's converted
161// to Number too) is converted to primitive using ToPrimitive with NO HINT.
162// Having no hint means Date gets a string hint, and everything else gets
163// a number hint.
164
165testEqual(new Boolean(true), true);
166testEqual(new Boolean(true), 1);  // First to primtive boolean, then to number.
167testEqual(new Boolean(false), false);
168testEqual(new Boolean(false), 0);
169
170testEqual(new Wrapper(true), true);
171testEqual(new Wrapper(true), 1);
172testEqual(new Wrapper(false), false);
173testEqual(new Wrapper(false), 0);
174
175testEqual(new Wrapper2(true), true);
176testEqual(new Wrapper2(true), 1);
177testEqual(new Wrapper2(false), false);
178testEqual(new Wrapper2(false), 0);
179
180testEqual(new Number(1), true);
181testEqual(new Number(1), 1);
182testEqual(new Number(0), false);
183testEqual(new Number(0), 0);
184
185// Date objects convert to string, not number (and the string does not
186// convert to the number).
187testEqual(new Date(42), String(new Date(42)));
188testNotEqual(new Date(42), Number(new Date(42)));
189var dnow = new Date();
190testEqual(dnow, dnow);
191testEqual(dnow, String(dnow));
192testNotEqual(dnow, Number(dnow));
193
194// Doesn't just call toString, but uses ToPrimitive which tries toString first
195// and valueOf second.
196dnow.toString = null;
197testEqual(dnow, Number(dnow));
198dnow.valueOf = function () { return "42"; };
199testEqual(dnow, 42);
200dnow.toString = function () { return "1"; };
201testEqual(dnow, true);
202
203
204// Objects compared to other objects, or to null and undefined, are not
205// converted to primitive.
206testNotEqual(new Wrapper(null), new Wrapper(null));
207testNotEqual(new Boolean(true), new Boolean(true));
208testNotEqual(new Boolean(false), new Boolean(false));
209testNotEqual(new String("a"), new String("a"));
210testNotEqual(new Number(42), new Number(42));
211testNotEqual(new Date(42), new Date(42));
212testNotEqual(new Array(42), new Array(42));
213testNotEqual(new Object(), new Object());
214
215// Object that can't be converted to primitive.
216var badObject = {
217  valueOf: null,
218  toString: function() {
219    return this;  // Not primitive.
220  }
221};
222
223testEqual(badObject, badObject);
224testNotEqual(badObject, {});
225testNotEqual(badObject, null);
226testNotEqual(badObject, undefined);
227// Forcing conversion will throw.
228function testBadConversion(value) {
229  assertThrows(function() { return badObject == value; });
230  assertThrows(function() { return badObject != value; });
231  assertThrows(function() { return value == badObject; });
232  assertThrows(function() { return value != badObject; });
233}
234testBadConversion(0);
235testBadConversion("string");
236testBadConversion(true);
237