1
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
159
160
161
162
163
164
165
166
|
/* -*- tab-width: 2; indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
File Name: 15.5.4.9-1.js
ECMA Section: 15.5.4.9 String.prototype.substring( start )
Description:
15.5.4.9 String.prototype.substring(start)
Returns a substring of the result of converting this object to a string,
starting from character position start and running to the end of the
string. The result is a string value, not a String object.
If the argument is NaN or negative, it is replaced with zero; if the
argument is larger than the length of the string, it is replaced with the
length of the string.
When the substring method is called with one argument start, the following
steps are taken:
1.Call ToString, giving it the this value as its argument.
2.Call ToInteger(start).
3.Compute the number of characters in Result(1).
4.Compute min(max(Result(2), 0), Result(3)).
5.Return a string whose length is the difference between Result(3) and Result(4),
containing characters from Result(1), namely the characters with indices Result(4)
through Result(3)1, in ascending order.
Author: christine@netscape.com
Date: 12 november 1997
*/
var SECTION = "15.5.4.9-1";
var VERSION = "ECMA_1";
startTest();
var TITLE = "String.prototype.substring( start )";
writeHeaderToLog( SECTION + " "+ TITLE);
new TestCase( SECTION, "String.prototype.substring.length", 2, String.prototype.substring.length );
// test cases for when substring is called with no arguments.
// this is a string object
new TestCase( SECTION,
"var s = new String('this is a string object'); typeof s.substring()",
"string",
eval("var s = new String('this is a string object'); typeof s.substring()") );
new TestCase( SECTION,
"var s = new String(''); s.substring()",
"",
eval("var s = new String(''); s.substring()") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring()",
"this is a string object",
eval("var s = new String('this is a string object'); s.substring()") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(NaN)",
"this is a string object",
eval("var s = new String('this is a string object'); s.substring(NaN)") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(-0.01)",
"this is a string object",
eval("var s = new String('this is a string object'); s.substring(-0.01)") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(s.length)",
"",
eval("var s = new String('this is a string object'); s.substring(s.length)") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(s.length+1)",
"",
eval("var s = new String('this is a string object'); s.substring(s.length+1)") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(Infinity)",
"",
eval("var s = new String('this is a string object'); s.substring(Infinity)") );
new TestCase( SECTION,
"var s = new String('this is a string object'); s.substring(-Infinity)",
"this is a string object",
eval("var s = new String('this is a string object'); s.substring(-Infinity)") );
// this is not a String object, start is not an integer
new TestCase( SECTION,
"var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring()",
"1,2,3,4,5",
eval("var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring()") );
new TestCase( SECTION,
"var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring(true)",
",2,3,4,5",
eval("var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring(true)") );
new TestCase( SECTION,
"var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring('4')",
"3,4,5",
eval("var s = new Array(1,2,3,4,5); s.substring = String.prototype.substring; s.substring('4')") );
new TestCase( SECTION,
"var s = new Array(); s.substring = String.prototype.substring; s.substring('4')",
"",
eval("var s = new Array(); s.substring = String.prototype.substring; s.substring('4')") );
// this is an object object
new TestCase( SECTION,
"var obj = new Object(); obj.substring = String.prototype.substring; obj.substring(8)",
"Object]",
eval("var obj = new Object(); obj.substring = String.prototype.substring; obj.substring(8)") );
// this is a function object
new TestCase( SECTION,
"var obj = new Function(); obj.substring = String.prototype.substring; obj.toString = Object.prototype.toString; obj.substring(8)",
"Function]",
eval("var obj = new Function(); obj.substring = String.prototype.substring; obj.toString = Object.prototype.toString; obj.substring(8)") );
// this is a number object
new TestCase( SECTION,
"var obj = new Number(NaN); obj.substring = String.prototype.substring; obj.substring(false)",
"NaN",
eval("var obj = new Number(NaN); obj.substring = String.prototype.substring; obj.substring(false)") );
// this is the Math object
new TestCase( SECTION,
"var obj = Math; obj.substring = String.prototype.substring; obj.substring(Math.PI)",
"ject Math]",
eval("var obj = Math; obj.substring = String.prototype.substring; obj.substring(Math.PI)") );
// this is a Boolean object
new TestCase( SECTION,
"var obj = new Boolean(); obj.substring = String.prototype.substring; obj.substring(new Array())",
"false",
eval("var obj = new Boolean(); obj.substring = String.prototype.substring; obj.substring(new Array())") );
// this is a user defined object
new TestCase( SECTION,
"var obj = new MyObject( null ); obj.substring(0)",
"null",
eval( "var obj = new MyObject( null ); obj.substring(0)") );
test();
function MyObject( value ) {
this.value = value;
this.substring = String.prototype.substring;
this.toString = new Function ( "return this.value+''" );
}
|
