commit ac93765efc9f9f32978da23ef458b4447d5652c6
author Xueqiao Xu <xueqiaoxu@gmail.com> Tue Mar 27 04:38:12 2012
committer Xueqiao Xu <xueqiaoxu@gmail.com> Tue Mar 27 04:38:12 2012
tree 3f42e0ba97d68513c274635e5d0da01d2d7e0ad1
parent 7398dbb14f5b7d7a7fd316f950db32629a2b3b9f

fix: array compare function

lib/difflib.js

diff --git a/lib/difflib.js b/lib/difflib.js
index e00e5ab..6d0cfc0 100644
--- a/lib/difflib.js
+++ b/lib/difflib.js
@@ -43,12 +43,13 @@
   };
 
   _arrayCmp = function(a, b) {
-    var i, _ref;
-    for (i = 0, _ref = max(a.length, b.length); 0 <= _ref ? i < _ref : i > _ref; 0 <= _ref ? i++ : i--) {
+    var i, la, lb, _ref, _ref2;
+    _ref = [a.length, b.length], la = _ref[0], lb = _ref[1];
+    for (i = 0, _ref2 = min(la, lb); 0 <= _ref2 ? i < _ref2 : i > _ref2; 0 <= _ref2 ? i++ : i--) {
       if (a[i] < b[i]) return -1;
       if (a[i] > b[i]) return 1;
     }
-    return 0;
+    return la - lb;
   };
 
   SequenceMatcher = (function() {
@@ -628,7 +629,7 @@
         result.push([s.ratio(), x]);
       }
     }
-    result = Heap.nlargest(n, result);
+    result = Heap.nlargest(n, result, _arrayCmp);
     _results = [];
     for (_j = 0, _len2 = result.length; _j < _len2; _j++) {
       _ref = result[_j], score = _ref[0], x = _ref[1];
@@ -1318,6 +1319,8 @@
     return lines;
   };
 
+  exports._arrayCmp = _arrayCmp;
+
   exports.SequenceMatcher = SequenceMatcher;
 
   exports.getCloseMatches = getCloseMatches;

src/difflib.coffee

diff --git a/src/difflib.coffee b/src/difflib.coffee
index 3eb1c97..0c6887a 100644
--- a/src/difflib.coffee
+++ b/src/difflib.coffee
@@ -33,10 +33,11 @@
   if length then (2.0 * matches / length) else 1.0
 
 _arrayCmp = (a, b) ->
-  for i in [0...max(a.length, b.length)]
+  [la, lb] = [a.length, b.length]
+  for i in [0...min(la, lb)]
     return -1 if a[i] < b[i]
     return 1 if a[i] > b[i]
-  0
+  la - lb
 
 class SequenceMatcher
   ###
@@ -711,7 +712,7 @@
       result.push([s.ratio(), x])
 
   # Move the best scorers to head of list
-  result = Heap.nlargest(n, result)
+  result = Heap.nlargest(n, result, _arrayCmp)
   # Strip scores for the best n matches
   (x for [score, x] in result)
 
@@ -1314,6 +1315,7 @@
   lines
 
 # exports to global
+exports._arrayCmp           = _arrayCmp
 exports.SequenceMatcher     = SequenceMatcher
 exports.getCloseMatches     = getCloseMatches
 exports._countLeading       = _countLeading

test/global.coffee

diff --git a/test/global.coffee b/test/global.coffee
index a3eaf60..a5bb19c 100644
--- a/test/global.coffee
+++ b/test/global.coffee
@@ -1,4 +1,5 @@
 {
+  _arrayCmp,
   getCloseMatches,
   _countLeading,
   IS_LINE_JUNK,
@@ -13,6 +14,16 @@
 
 suite 'global'
 
+test '._arrayCmp', ->
+  _arrayCmp([1, 2], [1, 2]).should.eql 0
+  _arrayCmp([1, 2, 3], [1, 2, 4]).should.below 0
+  _arrayCmp([1], [1, 2]).should.below 0
+  _arrayCmp([2, 1], [1, 2]).should.above 0
+  _arrayCmp([2, 0, 0], [2, 3]).should.below 0
+  _arrayCmp([], [1]).should.below 0
+  _arrayCmp([1], []).should.above 0
+  _arrayCmp([], []).should.eql 0
+
 test '.getCloseMatches', ->
  getCloseMatches('appel', ['ape', 'apple', 'peach', 'puppy'])
    .should.eql ['apple', 'ape']