mypy: Turn on return value checks

Its a shame GvR is married to "return None"
https://github.com/python/mypy/issues/7511

kitty/rc/close_tab.py

@@ -35,6 +35,7 @@ If specified close the tab of the window this command is run in, rather than the
         for tab in self.tabs_for_match_payload(boss, window, payload_get):
             if tab:
                 boss.close_tab_no_confirm(tab)
+        return None
 
 
 close_tab = CloseTab()

kitty/rc/close_window.py

@@ -34,6 +34,7 @@ If specified close the window this command is run in, rather than the active win
         for window in self.windows_for_match_payload(boss, window, payload_get):
             if window:
                 boss.close_window(window)
+        return None
 
 
 close_window = CloseWindow()

kitty/rc/create_marker.py

@@ -45,6 +45,7 @@ If specified apply marker to the window this command is run in, rather than the
         args = payload_get('marker_spec')
         for window in self.windows_for_match_payload(boss, window, payload_get):
             window.set_marker(args)
+        return None
 
 
 create_marker = CreateMarker()

kitty/rc/detach_tab.py

@@ -57,6 +57,7 @@ If specified detach the tab this command is run in, rather than the active tab.
 
         for tab in tabs:
             boss._move_tab_to(tab=tab, **kwargs)
+        return None
 
 
 detach_tab = DetachTab()

kitty/rc/detach_window.py

@@ -53,6 +53,7 @@ If specified detach the window this command is run in, rather than the active wi
         kwargs = {'target_os_window_id': newval} if target_tab_id is None else {'target_tab_id': target_tab_id}
         for window in windows:
             boss._move_window_to(window=window, **kwargs)
+        return None
 
 
 detach_window = DetachWindow()

kitty/rc/disable_ligatures.py

@@ -52,6 +52,7 @@ cause ligatures to be changed in all windows.
     def response_from_kitty(self, boss: Boss, window: Optional[Window], payload_get: PayloadGetType) -> ResponseType:
         windows = self.windows_for_payload(boss, window, payload_get)
         boss.disable_ligatures_in(windows, payload_get('strategy'))
+        return None
 # }}}
 
 

kitty/rc/env.py

@@ -43,6 +43,7 @@ class Env(RemoteCommand):
             else:
                 env.pop(k, None)
         set_default_env(env)
+        return None
 
 
 env = Env()

kitty/rc/focus_tab.py

@@ -41,6 +41,7 @@ using this option means that you will not be notified of failures.
             if tab:
                 boss.set_active_tab(tab)
                 break
+        return None
 
 
 focus_tab = FocusTab()

kitty/rc/focus_window.py

@@ -43,6 +43,7 @@ the command will exit with a success code.
                 if os_window_id:
                     focus_os_window(os_window_id, True)
                 break
+        return None
 
 
 focus_window = FocusWindow()

kitty/rc/goto_layout.py

@@ -47,6 +47,7 @@ class GotoLayout(RemoteCommand):
                     tab.goto_layout(payload_get('layout'), raise_exception=True)
                 except ValueError:
                     raise UnknownLayout('The layout {} is unknown or disabled'.format(payload_get('layout')))
+        return None
 
 
 goto_layout = GotoLayout()

kitty/rc/kitten.py

@@ -51,6 +51,7 @@ class Kitten(RemoteCommand):
                 break
         if isinstance(retval, (str, bool)):
             return retval
+        return None
 
 
 kitten = Kitten()

kitty/rc/last_used_layout.py

@@ -45,6 +45,7 @@ the command will exit with a success code.
         for tab in self.tabs_for_match_payload(boss, window, payload_get):
             if tab:
                 tab.last_used_layout()
+        return None
 
 
 last_used_layout = LastUsedLayout()

kitty/rc/remove_marker.py

@@ -34,6 +34,7 @@ If specified apply marker to the window this command is run in, rather than the
     def response_from_kitty(self, boss: Boss, window: Optional[Window], payload_get: PayloadGetType) -> ResponseType:
         for window in self.windows_for_match_payload(boss, window, payload_get):
             window.remove_marker()
+        return None
 
 
 remove_marker = RemoveMarker()

kitty/rc/resize_os_window.py

@@ -96,6 +96,7 @@ using this option means that you will not be notified of failures.
                     boss.toggle_fullscreen(os_window_id)
                 elif ac == 'toggle-maximized':
                     boss.toggle_maximized(os_window_id)
+        return None
 
 
 resize_os_window = ResizeOSWindow()

kitty/rc/scroll_window.py

@@ -69,6 +69,7 @@ class ScrollWindow(RemoteCommand):
                         func = getattr(window, f'scroll_{unit}_{direction}')
                         for i in range(abs(amt)):
                             func()
+        return None
 
 
 scroll_window = ScrollWindow()

kitty/rc/send_text.py

@@ -161,6 +161,7 @@ Do not send text to the active window, even if it is one of the matched windows.
                             window.write_to_child(kdata)
                     else:
                         window.write_to_child(data)
+        return None
 
 
 send_text = SendText()

kitty/rc/set_background_image.py

@@ -124,6 +124,7 @@ failed, the command will exit with a success code.
         except ValueError as err:
             err.hide_traceback = True  # type: ignore
             raise
+        return None
 
 
 set_background_image = SetBackgroundImage()

kitty/rc/set_background_opacity.py

@@ -53,6 +53,7 @@ cause colors to be changed in all windows.
         windows = self.windows_for_payload(boss, window, payload_get)
         for os_window_id in {w.os_window_id for w in windows}:
             boss._set_os_window_background_opacity(os_window_id, payload_get('opacity'))
+        return None
 
 
 set_background_opacity = SetBackgroundOpacity()

kitty/rc/set_colors.py

@@ -107,6 +107,7 @@ this option, any color arguments are ignored and --configured and --all are impl
             if default_bg_changed:
                 boss.default_bg_changed_for(w.id)
             w.refresh()
+        return None
 
 
 set_colors = SetColors()

kitty/rc/set_enabled_layouts.py

@@ -64,6 +64,7 @@ as well.
         for tab in tabs:
             if tab:
                 tab.set_enabled_layouts(layouts)
+        return None
 
 
 set_enabled_layouts = SetEnabledLayouts()

kitty/rc/set_font_size.py

@@ -49,6 +49,7 @@ the font size for any newly created OS Windows in the future.
         boss.change_font_size(
             payload_get('all'),
             payload_get('increment_op'), payload_get('size'))
+        return None
 
 
 set_font_size = SetFontSize()

kitty/rc/set_spacing.py

@@ -119,6 +119,7 @@ windows).
 
         for tab in dirtied_tabs.values():
             tab.relayout()
+        return None
 
 
 set_spacing = SetSpacing()

kitty/rc/set_tab_color.py

@@ -76,6 +76,7 @@ If specified close the tab this command is run in, rather than the active tab.
                 for k, v in s.items():
                     setattr(tab, k, v)
                 tab.mark_tab_bar_dirty()
+        return None
 
 
 set_tab_color = SetTabColor()

kitty/rc/set_tab_title.py

@@ -37,6 +37,7 @@ class SetTabTitle(RemoteCommand):
         for tab in self.tabs_for_match_payload(boss, window, payload_get):
             if tab:
                 tab.set_title(payload_get('title'))
+        return None
 
 
 set_tab_title = SetTabTitle()

kitty/rc/set_window_title.py

@@ -57,6 +57,7 @@ want to allow other programs to change it afterwards, use this option.
                     window.title_changed(payload_get('title'))
                 else:
                     window.set_title(payload_get('title'))
+        return None
 
 
 set_window_title = SetWindowTitle()

kitty/rc/signal_child.py

@@ -47,6 +47,7 @@ class SignalChild(RemoteCommand):
         for window in windows:
             if window:
                 window.signal_child(*signals)
+        return None
 
 
 signal_child = SignalChild()