| Leo Repp | 58b9f11 | 2021-11-22 11:57:47 +0100 | [diff] [blame^] | 1 | module.exports = exports = abbrev.abbrev = abbrev |
| 2 | |
| 3 | abbrev.monkeyPatch = monkeyPatch |
| 4 | |
| 5 | function monkeyPatch () { |
| 6 | Object.defineProperty(Array.prototype, 'abbrev', { |
| 7 | value: function () { return abbrev(this) }, |
| 8 | enumerable: false, configurable: true, writable: true |
| 9 | }) |
| 10 | |
| 11 | Object.defineProperty(Object.prototype, 'abbrev', { |
| 12 | value: function () { return abbrev(Object.keys(this)) }, |
| 13 | enumerable: false, configurable: true, writable: true |
| 14 | }) |
| 15 | } |
| 16 | |
| 17 | function abbrev (list) { |
| 18 | if (arguments.length !== 1 || !Array.isArray(list)) { |
| 19 | list = Array.prototype.slice.call(arguments, 0) |
| 20 | } |
| 21 | for (var i = 0, l = list.length, args = [] ; i < l ; i ++) { |
| 22 | args[i] = typeof list[i] === "string" ? list[i] : String(list[i]) |
| 23 | } |
| 24 | |
| 25 | // sort them lexicographically, so that they're next to their nearest kin |
| 26 | args = args.sort(lexSort) |
| 27 | |
| 28 | // walk through each, seeing how much it has in common with the next and previous |
| 29 | var abbrevs = {} |
| 30 | , prev = "" |
| 31 | for (var i = 0, l = args.length ; i < l ; i ++) { |
| 32 | var current = args[i] |
| 33 | , next = args[i + 1] || "" |
| 34 | , nextMatches = true |
| 35 | , prevMatches = true |
| 36 | if (current === next) continue |
| 37 | for (var j = 0, cl = current.length ; j < cl ; j ++) { |
| 38 | var curChar = current.charAt(j) |
| 39 | nextMatches = nextMatches && curChar === next.charAt(j) |
| 40 | prevMatches = prevMatches && curChar === prev.charAt(j) |
| 41 | if (!nextMatches && !prevMatches) { |
| 42 | j ++ |
| 43 | break |
| 44 | } |
| 45 | } |
| 46 | prev = current |
| 47 | if (j === cl) { |
| 48 | abbrevs[current] = current |
| 49 | continue |
| 50 | } |
| 51 | for (var a = current.substr(0, j) ; j <= cl ; j ++) { |
| 52 | abbrevs[a] = current |
| 53 | a += current.charAt(j) |
| 54 | } |
| 55 | } |
| 56 | return abbrevs |
| 57 | } |
| 58 | |
| 59 | function lexSort (a, b) { |
| 60 | return a === b ? 0 : a > b ? 1 : -1 |
| 61 | } |