Show the user an error message when pressing a key results in an exception

kitty/boss.py

@@ -1133,10 +1133,14 @@ class Boss:
         ''')
     def combine(self, actions: Tuple[KeyAction, ...], window_for_dispatch: Optional[Window] = None, dispatch_type: str = 'KeyPress') -> bool:
         consumed = False
-        if self.dispatch_action(actions[0], window_for_dispatch, dispatch_type):
+        try:
+            if self.dispatch_action(actions[0], window_for_dispatch, dispatch_type):
+                consumed = True
+                if len(actions) > 1:
+                    self.drain_actions(list(actions[1:]), window_for_dispatch, dispatch_type)
+        except Exception as e:
+            self.show_error('Key action failed', f'{actions[0].pretty()}\n{e}')
             consumed = True
-            if len(actions) > 1:
-                self.drain_actions(list(actions[1:]), window_for_dispatch, dispatch_type)
         return consumed
 
     def on_focus(self, os_window_id: int, focused: bool) -> None:

kitty/conf/utils.py

@@ -260,6 +260,12 @@ class KeyAction(NamedTuple):
             return f'KeyAction({self.func!r}, {self.args!r})'
         return f'KeyAction({self.func!r})'
 
+    def pretty(self) -> str:
+        ans = self.func
+        for x in self.args:
+            ans += f' {x}'
+        return ans
+
 
 def parse_kittens_func_args(action: str, args_funcs: Dict[str, KeyFunc[Tuple[str, Any]]]) -> KeyAction:
     parts = action.strip().split(' ', 1)