Correctly recognize special keys in key-shortcuts

Special keys in config should follow similiar syntax to that used in
vim:

left arrow = `<Left>`
right arrow = `<Right>`
page down = `<Page down>`
home = `<Home>`
esc = `<Esc>`
F4 = `<F4>`
Ctrl+s = `<C-s>`
Meta+k = `<M-k>`

Examples:
=========

```ini
[column_keymap]
<Left> = prev_column
<Right> = next_column
<Esc>k = home
<C-s> = tag {} foo 1
<M-s> = tag {} foo
```

test/data/ConfigTest6.conf

 [column_keymap]
 up = up
+<Left> = prev_column
+<Esc>d = delete_column

test/test_config.py

@@ -159,5 +159,12 @@ class ConfigTest(TopydoTest):
         self.assertEqual(keymap['up'], 'up')
         self.assertIn('u', keystates)
 
+        self.assertEqual(keymap['<Left>'], 'prev_column')
+        self.assertNotIn('<Lef', keystates)
+
+        self.assertEqual(keymap['<Esc>d'], 'delete_column')
+        self.assertNotIn('<Esc', keystates)
+        self.assertIn('<Esc>', keystates)
+
 if __name__ == '__main__':
     unittest.main()

topydo.conf

@@ -88,3 +88,5 @@ D = delete_column
 Y = copy_column
 L = swap_left
 R = swap_right
+<Left> = prev_column
+<Right> = next_column

topydo/lib/Config.py

@@ -16,6 +16,7 @@
 
 import configparser
 import os
+import re
 import shlex
 
 from itertools import accumulate
@@ -136,6 +137,8 @@ class _Config:
                 'Y': 'copy_column',
                 'L': 'swap_left',
                 'R': 'swap_right',
+                '<Left>': 'prev_column',
+                '<Right>': 'next_column',
             },
         }
 
@@ -350,8 +353,9 @@ class _Config:
 
         for combo, action in shortcuts:
             # add all possible prefixes to keystates
-            if len(combo) > 1:
-                keystates |= set(accumulate(combo[:-1]))
+            combo_as_list = re.split('(<[A-Z].+?>|.)', combo)[1::2]
+            if len(combo_as_list) > 1:
+                keystates |= set(accumulate(combo_as_list[:-1]))
 
             if action in ['pri', 'postpone', 'postpone_s']:
                 keystates.add(combo)

topydo/lib/Utils.py

@@ -94,3 +94,18 @@ def get_terminal_size(p_getter=None):
             get_terminal_size.getter = inner
 
         return get_terminal_size.getter()
+
+
+def translate_key_to_config(p_key):
+    """
+    Translates urwid key event to form understandable by topydo config parser.
+    """
+    if len(p_key) > 1:
+        key = p_key.capitalize()
+        if key.startswith('Ctrl') or key.startswith('Meta'):
+            key = key[0] + '-' + key[5:]
+        key = '<' + key + '>'
+    else:
+        key = p_key
+
+    return key

topydo/ui/Main.py

@@ -232,7 +232,6 @@ class UIApplication(CLIApplicationBase):
         self.column_mode = _COPY_COLUMN
         self._viewwidget_visible = True
 
-
     def _column_action_handler(self, p_action):
         dispatch = {
             'first_column': self._focus_first_column,
@@ -252,8 +251,6 @@ class UIApplication(CLIApplicationBase):
     def _handle_input(self, p_input):
         dispatch = {
             ':': self._focus_commandline,
-            'left': self._focus_previous_column,
-            'right': self._focus_next_column,
         }
 
         try:

topydo/ui/TodoListWidget.py

@@ -17,6 +17,7 @@
 import urwid
 
 from topydo.ui.TodoWidget import TodoWidget
+from topydo.lib.Utils import translate_key_to_config
 
 
 class PendingAction(object):
@@ -135,7 +136,7 @@ class TodoListWidget(urwid.LineBox):
         keymap, keystates = self.keymap
 
         shortcut = self.keystate or ''
-        shortcut += p_key
+        shortcut += translate_key_to_config(p_key)
 
         try:
             action = keymap[shortcut]