| // Copyright 2014 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| 'use strict'; |
| |
| // This file relies on the fact that the following declaration has been made |
| // in runtime.js: |
| // var $String = global.String; |
| // var $Array = global.Array; |
| |
| // ------------------------------------------------------------------- |
| |
| // ES6 draft 01-20-14, section 21.1.3.13 |
| function StringRepeat(count) { |
| CHECK_OBJECT_COERCIBLE(this, "String.prototype.repeat"); |
| |
| var s = TO_STRING_INLINE(this); |
| var n = ToInteger(count); |
| if (n < 0 || !NUMBER_IS_FINITE(n)) { |
| throw MakeRangeError("invalid_count_value", []); |
| } |
| |
| var elements = new InternalArray(n); |
| for (var i = 0; i < n; i++) { |
| elements[i] = s; |
| } |
| |
| return %StringBuilderConcat(elements, n, ""); |
| } |
| |
| |
| // ES6 draft 04-05-14, section 21.1.3.18 |
| function StringStartsWith(searchString /* position */) { // length == 1 |
| CHECK_OBJECT_COERCIBLE(this, "String.prototype.startsWith"); |
| |
| var s = TO_STRING_INLINE(this); |
| |
| if (IS_REGEXP(searchString)) { |
| throw MakeTypeError("first_argument_not_regexp", |
| ["String.prototype.startsWith"]); |
| } |
| |
| var ss = TO_STRING_INLINE(searchString); |
| var pos = 0; |
| if (%_ArgumentsLength() > 1) { |
| pos = %_Arguments(1); // position |
| pos = ToInteger(pos); |
| } |
| |
| var s_len = s.length; |
| var start = MathMin(MathMax(pos, 0), s_len); |
| var ss_len = ss.length; |
| if (ss_len + start > s_len) { |
| return false; |
| } |
| |
| return %StringIndexOf(s, ss, start) === start; |
| } |
| |
| |
| // ES6 draft 04-05-14, section 21.1.3.7 |
| function StringEndsWith(searchString /* position */) { // length == 1 |
| CHECK_OBJECT_COERCIBLE(this, "String.prototype.endsWith"); |
| |
| var s = TO_STRING_INLINE(this); |
| |
| if (IS_REGEXP(searchString)) { |
| throw MakeTypeError("first_argument_not_regexp", |
| ["String.prototype.endsWith"]); |
| } |
| |
| var ss = TO_STRING_INLINE(searchString); |
| var s_len = s.length; |
| var pos = s_len; |
| if (%_ArgumentsLength() > 1) { |
| var arg = %_Arguments(1); // position |
| if (!IS_UNDEFINED(arg)) { |
| pos = ToInteger(arg); |
| } |
| } |
| |
| var end = MathMin(MathMax(pos, 0), s_len); |
| var ss_len = ss.length; |
| var start = end - ss_len; |
| if (start < 0) { |
| return false; |
| } |
| |
| return %StringLastIndexOf(s, ss, start) === start; |
| } |
| |
| |
| // ES6 draft 04-05-14, section 21.1.3.6 |
| function StringContains(searchString /* position */) { // length == 1 |
| CHECK_OBJECT_COERCIBLE(this, "String.prototype.contains"); |
| |
| var s = TO_STRING_INLINE(this); |
| |
| if (IS_REGEXP(searchString)) { |
| throw MakeTypeError("first_argument_not_regexp", |
| ["String.prototype.contains"]); |
| } |
| |
| var ss = TO_STRING_INLINE(searchString); |
| var pos = 0; |
| if (%_ArgumentsLength() > 1) { |
| pos = %_Arguments(1); // position |
| pos = ToInteger(pos); |
| } |
| |
| var s_len = s.length; |
| var start = MathMin(MathMax(pos, 0), s_len); |
| var ss_len = ss.length; |
| if (ss_len + start > s_len) { |
| return false; |
| } |
| |
| return %StringIndexOf(s, ss, start) !== -1; |
| } |
| |
| |
| // ------------------------------------------------------------------- |
| |
| function ExtendStringPrototype() { |
| %CheckIsBootstrapping(); |
| |
| // Set up the non-enumerable functions on the String prototype object. |
| InstallFunctions($String.prototype, DONT_ENUM, $Array( |
| "repeat", StringRepeat, |
| "startsWith", StringStartsWith, |
| "endsWith", StringEndsWith, |
| "contains", StringContains |
| )); |
| } |
| |
| ExtendStringPrototype(); |