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// 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();
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