88 lines
2.8 KiB
JavaScript
88 lines
2.8 KiB
JavaScript
|
'use strict';
|
||
|
|
var regexpFlags = require('./regexp-flags');
|
||
|
|
var stickyHelpers = require('./regexp-sticky-helpers');
|
||
|
|
|
||
|
|
var nativeExec = RegExp.prototype.exec;
|
||
|
|
// This always refers to the native implementation, because the
|
||
|
|
// String#replace polyfill uses ./fix-regexp-well-known-symbol-logic.js,
|
||
|
|
// which loads this file before patching the method.
|
||
|
|
var nativeReplace = String.prototype.replace;
|
||
|
|
|
||
|
|
var patchedExec = nativeExec;
|
||
|
|
|
||
|
|
var UPDATES_LAST_INDEX_WRONG = (function () {
|
||
|
|
var re1 = /a/;
|
||
|
|
var re2 = /b*/g;
|
||
|
|
nativeExec.call(re1, 'a');
|
||
|
|
nativeExec.call(re2, 'a');
|
||
|
|
return re1.lastIndex !== 0 || re2.lastIndex !== 0;
|
||
|
|
})();
|
||
|
|
|
||
|
|
var UNSUPPORTED_Y = stickyHelpers.UNSUPPORTED_Y || stickyHelpers.BROKEN_CARET;
|
||
|
|
|
||
|
|
// nonparticipating capturing group, copied from es5-shim's String#split patch.
|
||
|
|
var NPCG_INCLUDED = /()??/.exec('')[1] !== undefined;
|
||
|
|
|
||
|
|
var PATCH = UPDATES_LAST_INDEX_WRONG || NPCG_INCLUDED || UNSUPPORTED_Y;
|
||
|
|
|
||
|
|
if (PATCH) {
|
||
|
|
patchedExec = function exec(str) {
|
||
|
|
var re = this;
|
||
|
|
var lastIndex, reCopy, match, i;
|
||
|
|
var sticky = UNSUPPORTED_Y && re.sticky;
|
||
|
|
var flags = regexpFlags.call(re);
|
||
|
|
var source = re.source;
|
||
|
|
var charsAdded = 0;
|
||
|
|
var strCopy = str;
|
||
|
|
|
||
|
|
if (sticky) {
|
||
|
|
flags = flags.replace('y', '');
|
||
|
|
if (flags.indexOf('g') === -1) {
|
||
|
|
flags += 'g';
|
||
|
|
}
|
||
|
|
|
||
|
|
strCopy = String(str).slice(re.lastIndex);
|
||
|
|
// Support anchored sticky behavior.
|
||
|
|
if (re.lastIndex > 0 && (!re.multiline || re.multiline && str[re.lastIndex - 1] !== '\n')) {
|
||
|
|
source = '(?: ' + source + ')';
|
||
|
|
strCopy = ' ' + strCopy;
|
||
|
|
charsAdded++;
|
||
|
|
}
|
||
|
|
// ^(? + rx + ) is needed, in combination with some str slicing, to
|
||
|
|
// simulate the 'y' flag.
|
||
|
|
reCopy = new RegExp('^(?:' + source + ')', flags);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (NPCG_INCLUDED) {
|
||
|
|
reCopy = new RegExp('^' + source + '$(?!\\s)', flags);
|
||
|
|
}
|
||
|
|
if (UPDATES_LAST_INDEX_WRONG) lastIndex = re.lastIndex;
|
||
|
|
|
||
|
|
match = nativeExec.call(sticky ? reCopy : re, strCopy);
|
||
|
|
|
||
|
|
if (sticky) {
|
||
|
|
if (match) {
|
||
|
|
match.input = match.input.slice(charsAdded);
|
||
|
|
match[0] = match[0].slice(charsAdded);
|
||
|
|
match.index = re.lastIndex;
|
||
|
|
re.lastIndex += match[0].length;
|
||
|
|
} else re.lastIndex = 0;
|
||
|
|
} else if (UPDATES_LAST_INDEX_WRONG && match) {
|
||
|
|
re.lastIndex = re.global ? match.index + match[0].length : lastIndex;
|
||
|
|
}
|
||
|
|
if (NPCG_INCLUDED && match && match.length > 1) {
|
||
|
|
// Fix browsers whose `exec` methods don't consistently return `undefined`
|
||
|
|
// for NPCG, like IE8. NOTE: This doesn' work for /(.?)?/
|
||
|
|
nativeReplace.call(match[0], reCopy, function () {
|
||
|
|
for (i = 1; i < arguments.length - 2; i++) {
|
||
|
|
if (arguments[i] === undefined) match[i] = undefined;
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
return match;
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = patchedExec;
|