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1// Copyright 2013 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'use strict';
29
30// This file relies on the fact that the following declaration has been made
31// in runtime.js:
32// var $String = global.String;
33// var $Array = global.Array;
34
35// -------------------------------------------------------------------
36
37// ES6 draft 07-15-13, section 15.5.3.21
38function StringRepeat(count) {
39  if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
40    throw MakeTypeError("called_on_null_or_undefined",
41                        ["String.prototype.repeat"]);
42  }
43
44  var s = TO_STRING_INLINE(this);
45  var n = ToInteger(count);
46  if (n < 0 || !NUMBER_IS_FINITE(n)) {
47    throw MakeRangeError("invalid_count_value", []);
48  }
49
50  var elements = new InternalArray(n);
51  for (var i = 0; i < n; i++) {
52    elements[i] = s;
53  }
54
55  return %StringBuilderConcat(elements, n, "");
56}
57
58
59// ES6 draft 07-15-13, section 15.5.3.22
60function StringStartsWith(searchString /* position */) {  // length == 1
61  if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
62    throw MakeTypeError("called_on_null_or_undefined",
63                        ["String.prototype.startsWith"]);
64  }
65
66  var s = TO_STRING_INLINE(this);
67  var ss = TO_STRING_INLINE(searchString);
68  var pos = 0;
69  if (%_ArgumentsLength() > 1) {
70    pos = %_Arguments(1);  // position
71    pos = ToInteger(pos);
72  }
73
74  var s_len = s.length;
75  var start = MathMin(MathMax(pos, 0), s_len);
76  var ss_len = ss.length;
77  if (ss_len + start > s_len) {
78    return false;
79  }
80
81  return %StringIndexOf(s, ss, start) === start;
82}
83
84
85// ES6 draft 07-15-13, section 15.5.3.23
86function StringEndsWith(searchString /* position */) {  // length == 1
87  if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
88    throw MakeTypeError("called_on_null_or_undefined",
89                        ["String.prototype.endsWith"]);
90  }
91
92  var s = TO_STRING_INLINE(this);
93  var ss = TO_STRING_INLINE(searchString);
94  var s_len = s.length;
95  var pos = s_len;
96  if (%_ArgumentsLength() > 1) {
97    var arg = %_Arguments(1);  // position
98    if (!IS_UNDEFINED(arg)) {
99      pos = ToInteger(arg);
100    }
101  }
102
103  var end = MathMin(MathMax(pos, 0), s_len);
104  var ss_len = ss.length;
105  var start = end - ss_len;
106  if (start < 0) {
107    return false;
108  }
109
110  return %StringLastIndexOf(s, ss, start) === start;
111}
112
113
114// ES6 draft 07-15-13, section 15.5.3.24
115function StringContains(searchString /* position */) {  // length == 1
116  if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
117    throw MakeTypeError("called_on_null_or_undefined",
118                        ["String.prototype.contains"]);
119  }
120
121  var s = TO_STRING_INLINE(this);
122  var ss = TO_STRING_INLINE(searchString);
123  var pos = 0;
124  if (%_ArgumentsLength() > 1) {
125    pos = %_Arguments(1);  // position
126    pos = ToInteger(pos);
127  }
128
129  var s_len = s.length;
130  var start = MathMin(MathMax(pos, 0), s_len);
131  var ss_len = ss.length;
132  if (ss_len + start > s_len) {
133    return false;
134  }
135
136  return %StringIndexOf(s, ss, start) !== -1;
137}
138
139
140// -------------------------------------------------------------------
141
142function ExtendStringPrototype() {
143  %CheckIsBootstrapping();
144
145  // Set up the non-enumerable functions on the String prototype object.
146  InstallFunctions($String.prototype, DONT_ENUM, $Array(
147    "repeat", StringRepeat,
148    "startsWith", StringStartsWith,
149    "endsWith", StringEndsWith,
150    "contains", StringContains
151  ));
152}
153
154ExtendStringPrototype();
155