Added tox configuration

... and fixed pep8 warnings. There's a lot of them that are still
ignored, but that's because it's too much of a step to take at once.

core/gui/prioritize_dialog.py

@@ -1,9 +1,9 @@
 # Created By: Virgil Dupras
 # Created On: 2011-09-06
 # Copyright 2014 Hardcoded Software (http://www.hardcoded.net)
-# 
-# This software is licensed under the "BSD" License as described in the "LICENSE" file, 
-# which should be included with this package. The terms are also available at 
+#
+# This software is licensed under the "BSD" License as described in the "LICENSE" file,
+# which should be included with this package. The terms are also available at
 # http://www.hardcoded.net/licenses/bsd_license
 
 from hscommon.gui.base import GUIObject
@@ -13,7 +13,7 @@ class CriterionCategoryList(GUISelectableList):
     def __init__(self, dialog):
         self.dialog = dialog
         GUISelectableList.__init__(self, [c.NAME for c in dialog.categories])
-    
+
     def _update_selection(self):
         self.dialog.select_category(self.dialog.categories[self.selected_index])
         GUISelectableList._update_selection(self)
@@ -22,10 +22,10 @@ class PrioritizationList(GUISelectableList):
     def __init__(self, dialog):
         self.dialog = dialog
         GUISelectableList.__init__(self)
-    
+
     def _refresh_contents(self):
         self[:] = [crit.display for crit in self.dialog.prioritizations]
-    
+
     def move_indexes(self, indexes, dest_index):
         indexes.sort()
         prilist = self.dialog.prioritizations
@@ -34,7 +34,7 @@ class PrioritizationList(GUISelectableList):
             del prilist[i]
         prilist[dest_index:dest_index] = selected
         self._refresh_contents()
-    
+
     def remove_selected(self):
         prilist = self.dialog.prioritizations
         for i in sorted(self.selected_indexes, reverse=True):
@@ -51,15 +51,15 @@ class PrioritizeDialog(GUIObject):
         self.criteria_list = GUISelectableList()
         self.prioritizations = []
         self.prioritization_list = PrioritizationList(self)
-    
+
     #--- Override
     def _view_updated(self):
         self.category_list.select(0)
-    
+
     #--- Private
     def _sort_key(self, dupe):
         return tuple(crit.sort_key(dupe) for crit in self.prioritizations)
-    
+
     #--- Public
     def select_category(self, category):
         self.criteria = category.criteria_list()
@@ -71,10 +71,11 @@ class PrioritizeDialog(GUIObject):
             return
         crit = self.criteria[self.criteria_list.selected_index]
         self.prioritizations.append(crit)
+        del crit
         self.prioritization_list[:] = [crit.display for crit in self.prioritizations]
-    
+
     def remove_selected(self):
         self.prioritization_list.remove_selected()
-    
+
     def perform_reprioritization(self):
         self.app.reprioritize_groups(self._sort_key)