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/*!
* to-regex-range <https://github.com/micromatch/to-regex-range>
*
* Copyright (c) 2015-present, Jon Schlinkert.
* Released under the MIT License.
*/
'use strict';
const isNumber = require('is-number');
const toRegexRange = (min, max, options) => {
if (isNumber(min) === false) {
throw new TypeError('toRegexRange: expected the first argument to be a number');
}
if (max === void 0 || min === max) {
return String(min);
}
if (isNumber(max) === false) {
throw new TypeError('toRegexRange: expected the second argument to be a number.');
}
let opts = { relaxZeros: true, ...options };
if (typeof opts.strictZeros === 'boolean') {
opts.relaxZeros = opts.strictZeros === false;
}
let relax = String(opts.relaxZeros);
let shorthand = String(opts.shorthand);
let capture = String(opts.capture);
let wrap = String(opts.wrap);
let cacheKey = min + ':' + max + '=' + relax + shorthand + capture + wrap;
if (toRegexRange.cache.hasOwnProperty(cacheKey)) {
return toRegexRange.cache[cacheKey].result;
}
let a = Math.min(min, max);
let b = Math.max(min, max);
if (Math.abs(a - b) === 1) {
let result = min + '|' + max;
if (opts.capture) {
return `(${result})`;
}
if (opts.wrap === false) {
return result;
}
return `(?:${result})`;
}
let isPadded = hasPadding(min) || hasPadding(max);
let state = { min, max, a, b };
let positives = [];
let negatives = [];
if (isPadded) {
state.isPadded = isPadded;
state.maxLen = String(state.max).length;
}
if (a < 0) {
let newMin = b < 0 ? Math.abs(b) : 1;
negatives = splitToPatterns(newMin, Math.abs(a), state, opts);
a = state.a = 0;
}
if (b >= 0) {
positives = splitToPatterns(a, b, state, opts);
}
state.negatives = negatives;
state.positives = positives;
state.result = collatePatterns(negatives, positives, opts);
if (opts.capture === true) {
state.result = `(${state.result})`;
} else if (opts.wrap !== false && (positives.length + negatives.length) > 1) {
state.result = `(?:${state.result})`;
}
toRegexRange.cache[cacheKey] = state;
return state.result;
};
function collatePatterns(neg, pos, options) {
let onlyNegative = filterPatterns(neg, pos, '-', false, options) || [];
let onlyPositive = filterPatterns(pos, neg, '', false, options) || [];
let intersected = filterPatterns(neg, pos, '-?', true, options) || [];
let subpatterns = onlyNegative.concat(intersected).concat(onlyPositive);
return subpatterns.join('|');
}
function splitToRanges(min, max) {
let nines = 1;
let zeros = 1;
let stop = countNines(min, nines);
let stops = new Set([max]);
while (min <= stop && stop <= max) {
stops.add(stop);
nines += 1;
stop = countNines(min, nines);
}
stop = countZeros(max + 1, zeros) - 1;
while (min < stop && stop <= max) {
stops.add(stop);
zeros += 1;
stop = countZeros(max + 1, zeros) - 1;
}
stops = [...stops];
stops.sort(compare);
return stops;
}
/**
* Convert a range to a regex pattern
* @param {Number} `start`
* @param {Number} `stop`
* @return {String}
*/
function rangeToPattern(start, stop, options) {
if (start === stop) {
return { pattern: start, count: [], digits: 0 };
}
let zipped = zip(start, stop);
let digits = zipped.length;
let pattern = '';
let count = 0;
for (let i = 0; i < digits; i++) {
let [startDigit, stopDigit] = zipped[i];
if (startDigit === stopDigit) {
pattern += startDigit;
} else if (startDigit !== '0' || stopDigit !== '9') {
pattern += toCharacterClass(startDigit, stopDigit, options);
} else {
count++;
}
}
if (count) {
pattern += options.shorthand === true ? '\\d' : '[0-9]';
}
return { pattern, count: [count], digits };
}
function splitToPatterns(min, max, tok, options) {
let ranges = splitToRanges(min, max);
let tokens = [];
let start = min;
let prev;
for (let i = 0; i < ranges.length; i++) {
let max = ranges[i];
let obj = rangeToPattern(String(start), String(max), options);
let zeros = '';
if (!tok.isPadded && prev && prev.pattern === obj.pattern) {
if (prev.count.length > 1) {
prev.count.pop();
}
prev.count.push(obj.count[0]);
prev.string = prev.pattern + toQuantifier(prev.count);
start = max + 1;
continue;
}
if (tok.isPadded) {
zeros = padZeros(max, tok, options);
}
obj.string = zeros + obj.pattern + toQuantifier(obj.count);
tokens.push(obj);
start = max + 1;
prev = obj;
}
return tokens;
}
function filterPatterns(arr, comparison, prefix, intersection, options) {
let result = [];
for (let ele of arr) {
let { string } = ele;
// only push if _both_ are negative...
if (!intersection && !contains(comparison, 'string', string)) {
result.push(prefix + string);
}
// or _both_ are positive
if (intersection && contains(comparison, 'string', string)) {
result.push(prefix + string);
}
}
return result;
}
/**
* Zip strings
*/
function zip(a, b) {
let arr = [];
for (let i = 0; i < a.length; i++) arr.push([a[i], b[i]]);
return arr;
}
function compare(a, b) {
return a > b ? 1 : b > a ? -1 : 0;
}
function contains(arr, key, val) {
return arr.some(ele => ele[key] === val);
}
function countNines(min, len) {
return Number(String(min).slice(0, -len) + '9'.repeat(len));
}
function countZeros(integer, zeros) {
return integer - (integer % Math.pow(10, zeros));
}
function toQuantifier(digits) {
let [start = 0, stop = ''] = digits;
if (stop || start > 1) {
return `{${start + (stop ? ',' + stop : '')}}`;
}
return '';
}
function toCharacterClass(a, b, options) {
return `[${a}${(b - a === 1) ? '' : '-'}${b}]`;
}
function hasPadding(str) {
return /^-?(0+)\d/.test(str);
}
function padZeros(value, tok, options) {
if (!tok.isPadded) {
return value;
}
let diff = Math.abs(tok.maxLen - String(value).length);
let relax = options.relaxZeros !== false;
switch (diff) {
case 0:
return '';
case 1:
return relax ? '0?' : '0';
case 2:
return relax ? '0{0,2}' : '00';
default: {
return relax ? `0{0,${diff}}` : `0{${diff}}`;
}
}
}
/**
* Cache
*/
toRegexRange.cache = {};
toRegexRange.clearCache = () => (toRegexRange.cache = {});
/**
* Expose `toRegexRange`
*/
module.exports = toRegexRange;