Fixed: CPArrayController's addObject and CPArray's insertObject:inArraySortedByDescriptors:.

CPArray insertObject:inArraySortedByDescriptors: now quickly inserts objects at the end of the array if no sort descriptors are specified.

CPArrayController initialises its sort descriptors to an empty array.

Fixed: array controller's addObject added objects to the arranged objects array in a different order than in the content array if no sort descriptor was set.

AppKit/CPArrayController.j

@@ -108,6 +108,7 @@
 
     if (self)
     {
+        _sortDescriptors = [CPArray array];
         _selectionIndexes = [CPIndexSet indexSet];
     }