Format files with black

- Format all files with black
- Update tox.ini flake8 arguments to be compatible
- Add black to requirements-extra.txt
- Reduce ignored flake8 rules and fix a few violations

core/gui/directory_tree.py

@@ -1,9 +1,9 @@
 # Created By: Virgil Dupras
 # Created On: 2010-02-06
 # Copyright 2015 Hardcoded Software (http://www.hardcoded.net)
-# 
-# This software is licensed under the "GPLv3" 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 "GPLv3" License as described in the "LICENSE" file,
+# which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
 from hscommon.gui.tree import Tree, Node
@@ -13,6 +13,7 @@ from .base import DupeGuruGUIObject
 
 STATE_ORDER = [DirectoryState.Normal, DirectoryState.Reference, DirectoryState.Excluded]
 
+
 # Lazily loads children
 class DirectoryNode(Node):
     def __init__(self, tree, path, name):
@@ -21,29 +22,31 @@ class DirectoryNode(Node):
         self._directory_path = path
         self._loaded = False
         self._state = STATE_ORDER.index(self._tree.app.directories.get_state(path))
-    
+
     def __len__(self):
         if not self._loaded:
             self._load()
         return Node.__len__(self)
-    
+
     def _load(self):
         self.clear()
         subpaths = self._tree.app.directories.get_subfolders(self._directory_path)
         for path in subpaths:
             self.append(DirectoryNode(self._tree, path, path.name))
         self._loaded = True
-    
+
     def update_all_states(self):
-        self._state = STATE_ORDER.index(self._tree.app.directories.get_state(self._directory_path))
+        self._state = STATE_ORDER.index(
+            self._tree.app.directories.get_state(self._directory_path)
+        )
         for node in self:
             node.update_all_states()
-    
+
     # The state propery is an index to the combobox
     @property
     def state(self):
         return self._state
-    
+
     @state.setter
     def state(self, value):
         if value == self._state:
@@ -52,29 +55,29 @@ class DirectoryNode(Node):
         state = STATE_ORDER[value]
         self._tree.app.directories.set_state(self._directory_path, state)
         self._tree.update_all_states()
-    
+
 
 class DirectoryTree(Tree, DupeGuruGUIObject):
-    #--- model -> view calls:
+    # --- model -> view calls:
     # refresh()
     # refresh_states() # when only states label need to be refreshed
     #
     def __init__(self, app):
         Tree.__init__(self)
         DupeGuruGUIObject.__init__(self, app)
-    
+
     def _view_updated(self):
         self._refresh()
         self.view.refresh()
-    
+
     def _refresh(self):
         self.clear()
         for path in self.app.directories:
             self.append(DirectoryNode(self, path, str(path)))
-    
+
     def add_directory(self, path):
         self.app.add_directory(path)
-    
+
     def remove_selected(self):
         selected_paths = self.selected_paths
         if not selected_paths:
@@ -90,18 +93,17 @@ class DirectoryTree(Tree, DupeGuruGUIObject):
                 newstate = DirectoryState.Normal
             for node in nodes:
                 node.state = newstate
-    
+
     def select_all(self):
         self.selected_nodes = list(self)
         self.view.refresh()
-    
+
     def update_all_states(self):
         for node in self:
             node.update_all_states()
         self.view.refresh_states()
-    
-    #--- Event Handlers
+
+    # --- Event Handlers
     def directories_changed(self):
         self._refresh()
         self.view.refresh()
-