diff options
Diffstat (limited to 'node_modules/to-regex-range/index.js')
-rw-r--r-- | node_modules/to-regex-range/index.js | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/node_modules/to-regex-range/index.js b/node_modules/to-regex-range/index.js new file mode 100644 index 0000000..7bb5a74 --- /dev/null +++ b/node_modules/to-regex-range/index.js @@ -0,0 +1,294 @@ +/*! + * to-regex-range <https://github.com/jonschlinkert/to-regex-range> + * + * Copyright (c) 2015, 2017, Jon Schlinkert. + * Released under the MIT License. + */ + +'use strict'; + +var repeat = require('repeat-string'); +var isNumber = require('is-number'); +var cache = {}; + +function toRegexRange(min, max, options) { + if (isNumber(min) === false) { + throw new RangeError('toRegexRange: first argument is invalid.'); + } + + if (typeof max === 'undefined' || min === max) { + return String(min); + } + + if (isNumber(max) === false) { + throw new RangeError('toRegexRange: second argument is invalid.'); + } + + options = options || {}; + var relax = String(options.relaxZeros); + var shorthand = String(options.shorthand); + var capture = String(options.capture); + var key = min + ':' + max + '=' + relax + shorthand + capture; + if (cache.hasOwnProperty(key)) { + return cache[key].result; + } + + var a = Math.min(min, max); + var b = Math.max(min, max); + + if (Math.abs(a - b) === 1) { + var result = min + '|' + max; + if (options.capture) { + return '(' + result + ')'; + } + return result; + } + + var isPadded = padding(min) || padding(max); + var positives = []; + var negatives = []; + + var tok = {min: min, max: max, a: a, b: b}; + if (isPadded) { + tok.isPadded = isPadded; + tok.maxLen = String(tok.max).length; + } + + if (a < 0) { + var newMin = b < 0 ? Math.abs(b) : 1; + var newMax = Math.abs(a); + negatives = splitToPatterns(newMin, newMax, tok, options); + a = tok.a = 0; + } + + if (b >= 0) { + positives = splitToPatterns(a, b, tok, options); + } + + tok.negatives = negatives; + tok.positives = positives; + tok.result = siftPatterns(negatives, positives, options); + + if (options.capture && (positives.length + negatives.length) > 1) { + tok.result = '(' + tok.result + ')'; + } + + cache[key] = tok; + return tok.result; +} + +function siftPatterns(neg, pos, options) { + var onlyNegative = filterPatterns(neg, pos, '-', false, options) || []; + var onlyPositive = filterPatterns(pos, neg, '', false, options) || []; + var intersected = filterPatterns(neg, pos, '-?', true, options) || []; + var subpatterns = onlyNegative.concat(intersected).concat(onlyPositive); + return subpatterns.join('|'); +} + +function splitToRanges(min, max) { + min = Number(min); + max = Number(max); + + var nines = 1; + var stops = [max]; + var stop = +countNines(min, nines); + + while (min <= stop && stop <= max) { + stops = push(stops, stop); + nines += 1; + stop = +countNines(min, nines); + } + + var zeros = 1; + stop = countZeros(max + 1, zeros) - 1; + + while (min < stop && stop <= max) { + stops = push(stops, stop); + zeros += 1; + stop = countZeros(max + 1, zeros) - 1; + } + + 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: String(start), digits: []}; + } + + var zipped = zip(String(start), String(stop)); + var len = zipped.length, i = -1; + + var pattern = ''; + var digits = 0; + + while (++i < len) { + var numbers = zipped[i]; + var startDigit = numbers[0]; + var stopDigit = numbers[1]; + + if (startDigit === stopDigit) { + pattern += startDigit; + + } else if (startDigit !== '0' || stopDigit !== '9') { + pattern += toCharacterClass(startDigit, stopDigit); + + } else { + digits += 1; + } + } + + if (digits) { + pattern += options.shorthand ? '\\d' : '[0-9]'; + } + + return { pattern: pattern, digits: [digits] }; +} + +function splitToPatterns(min, max, tok, options) { + var ranges = splitToRanges(min, max); + var len = ranges.length; + var idx = -1; + + var tokens = []; + var start = min; + var prev; + + while (++idx < len) { + var range = ranges[idx]; + var obj = rangeToPattern(start, range, options); + var zeros = ''; + + if (!tok.isPadded && prev && prev.pattern === obj.pattern) { + if (prev.digits.length > 1) { + prev.digits.pop(); + } + prev.digits.push(obj.digits[0]); + prev.string = prev.pattern + toQuantifier(prev.digits); + start = range + 1; + continue; + } + + if (tok.isPadded) { + zeros = padZeros(range, tok); + } + + obj.string = zeros + obj.pattern + toQuantifier(obj.digits); + tokens.push(obj); + start = range + 1; + prev = obj; + } + + return tokens; +} + +function filterPatterns(arr, comparison, prefix, intersection, options) { + var res = []; + + for (var i = 0; i < arr.length; i++) { + var tok = arr[i]; + var ele = tok.string; + + if (options.relaxZeros !== false) { + if (prefix === '-' && ele.charAt(0) === '0') { + if (ele.charAt(1) === '{') { + ele = '0*' + ele.replace(/^0\{\d+\}/, ''); + } else { + ele = '0*' + ele.slice(1); + } + } + } + + if (!intersection && !contains(comparison, 'string', ele)) { + res.push(prefix + ele); + } + + if (intersection && contains(comparison, 'string', ele)) { + res.push(prefix + ele); + } + } + return res; +} + +/** + * Zip strings (`for in` can be used on string characters) + */ + +function zip(a, b) { + var arr = []; + for (var ch in a) arr.push([a[ch], b[ch]]); + return arr; +} + +function compare(a, b) { + return a > b ? 1 : b > a ? -1 : 0; +} + +function push(arr, ele) { + if (arr.indexOf(ele) === -1) arr.push(ele); + return arr; +} + +function contains(arr, key, val) { + for (var i = 0; i < arr.length; i++) { + if (arr[i][key] === val) { + return true; + } + } + return false; +} + +function countNines(min, len) { + return String(min).slice(0, -len) + repeat('9', len); +} + +function countZeros(integer, zeros) { + return integer - (integer % Math.pow(10, zeros)); +} + +function toQuantifier(digits) { + var start = digits[0]; + var stop = digits[1] ? (',' + digits[1]) : ''; + if (!stop && (!start || start === 1)) { + return ''; + } + return '{' + start + stop + '}'; +} + +function toCharacterClass(a, b) { + return '[' + a + ((b - a === 1) ? '' : '-') + b + ']'; +} + +function padding(str) { + return /^-?(0+)\d/.exec(str); +} + +function padZeros(val, tok) { + if (tok.isPadded) { + var diff = Math.abs(tok.maxLen - String(val).length); + switch (diff) { + case 0: + return ''; + case 1: + return '0'; + default: { + return '0{' + diff + '}'; + } + } + } + return val; +} + +/** + * Expose `toRegexRange` + */ + +module.exports = toRegexRange; |