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'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var $parseInt = GetIntrinsic('%parseInt%');
var inspect = require('object-inspect');
var regexTester = require('safe-regex-test');
var callBound = require('call-bind/callBound');
var every = require('../helpers/every');
var isDigit = regexTester(/^[0-9]$/);
var $charAt = callBound('String.prototype.charAt');
var $strSlice = callBound('String.prototype.slice');
var IsArray = require('./IsArray');
var Type = require('./Type');
var isInteger = require('../helpers/isInteger');
var isStringOrHole = require('../helpers/isStringOrHole');
// https://262.ecma-international.org/6.0/#sec-getsubstitution
// eslint-disable-next-line max-statements, max-lines-per-function
module.exports = function GetSubstitution(matched, str, position, captures, replacement) {
if (Type(matched) !== 'String') {
throw new $TypeError('Assertion failed: `matched` must be a String');
}
var matchLength = matched.length;
if (Type(str) !== 'String') {
throw new $TypeError('Assertion failed: `str` must be a String');
}
var stringLength = str.length;
if (!isInteger(position) || position < 0 || position > stringLength) {
throw new $TypeError('Assertion failed: `position` must be a nonnegative integer, and less than or equal to the length of `string`, got ' + inspect(position));
}
if (!IsArray(captures) || !every(captures, isStringOrHole)) {
throw new $TypeError('Assertion failed: `captures` must be a List of Strings, got ' + inspect(captures));
}
if (Type(replacement) !== 'String') {
throw new $TypeError('Assertion failed: `replacement` must be a String');
}
var tailPos = position + matchLength;
var m = captures.length;
var result = '';
for (var i = 0; i < replacement.length; i += 1) {
// if this is a $, and it's not the end of the replacement
var current = $charAt(replacement, i);
var isLast = (i + 1) >= replacement.length;
var nextIsLast = (i + 2) >= replacement.length;
if (current === '$' && !isLast) {
var next = $charAt(replacement, i + 1);
if (next === '$') {
result += '$';
i += 1;
} else if (next === '&') {
result += matched;
i += 1;
} else if (next === '`') {
result += position === 0 ? '' : $strSlice(str, 0, position - 1);
i += 1;
} else if (next === "'") {
result += tailPos >= stringLength ? '' : $strSlice(str, tailPos);
i += 1;
} else {
var nextNext = nextIsLast ? null : $charAt(replacement, i + 2);
if (isDigit(next) && next !== '0' && (nextIsLast || !isDigit(nextNext))) {
// $1 through $9, and not followed by a digit
var n = $parseInt(next, 10);
// if (n > m, impl-defined)
result += n <= m && Type(captures[n - 1]) === 'Undefined' ? '' : captures[n - 1];
i += 1;
} else if (isDigit(next) && (nextIsLast || isDigit(nextNext))) {
// $00 through $99
var nn = next + nextNext;
var nnI = $parseInt(nn, 10) - 1;
// if nn === '00' or nn > m, impl-defined
result += nn <= m && Type(captures[nnI]) === 'Undefined' ? '' : captures[nnI];
i += 2;
} else {
result += '$';
}
}
} else {
// the final $, or else not a $
result += $charAt(replacement, i);
}
}
return result;
};