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1module.exports = exports = abbrev.abbrev = abbrev
2
3abbrev.monkeyPatch = monkeyPatch
4
5function 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
17function 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
59function lexSort (a, b) {
60  return a === b ? 0 : a > b ? 1 : -1
61}
62