Fix file sorting for more than 11 elements

V8's Array.prototype.sort uses combination of quick sort and insertion sort.

The compare function should return integer (-1, 0, 1), but we were returning a boolean, which is incorrect. Boolean true equals to 1, but boolean false equals to 0, not -1. The way the condition was written, it worked for small arrays (where only insertion sort, which is stable, was used), but not for larger arrays, when unstable quick sort screwed it up.

lib/file-list.js

@@ -51,7 +51,9 @@ var GLOB_OPTS = {
 
 
 var byPath = function(a, b) {
-  return a.path > b.path;
+  if (a.path > b.path) return 1;
+  if (a.path < b.path) return -1;
+  return 0;
 };
 
 

test/unit/file-list.spec.coffee

@@ -15,6 +15,9 @@ describe 'file-list', ->
     '*.txt':      ['/c.txt', '/a.txt', '/b.txt']
     '*.js':       ['/folder', '/folder/x.js']
     '/a.*':       ['/a.txt']
+    # we need at least 11 elements to trigger V8's quick sort
+    '**':         ['/a.txt', '/b.txt', '/c.txt', '/a.txt', '/c.txt', '/b.txt', '/a.txt', '/c.txt',
+                   '/a.txt', '/a.txt', '/c.txt']
 
   mockFs = mocks.fs.create
     some:
@@ -177,6 +180,14 @@ describe 'file-list', ->
         expect(pathsFrom files.served).to.deep.equal ['/a.txt', '/some/a.js', '/b.txt', '/c.txt']
         done()
 
+    it 'should sort files within buckets (if more than 11 elements)', (done) ->
+      # regression for sorting many items
+      list = new m.List patterns('**'), [], null, preprocessMock
+
+      list.refresh().then (files) ->
+        expect(pathsFrom files.served).to.deep.equal ['/a.txt', '/b.txt', '/c.txt']
+        done()
+
     it 'should return only served files', (done) ->
       # /a.*       => /a.txt                   [served TRUE]
       # /some/*.js => /some/a.js, /some/b.js   [served FALSE]