[commands] Add missing and fix existing type annotations

discord/ext/commands/_types.py

@@ -45,18 +45,20 @@ else:
     P = TypeVar('P')
     MaybeCoroFunc = Tuple[P, T]
 
+_Bot = Union['Bot', 'AutoShardedBot']
 Coro = Coroutine[Any, Any, T]
 MaybeCoro = Union[T, Coro[T]]
 CoroFunc = Callable[..., Coro[Any]]
 
-ContextT = TypeVar('ContextT', bound='Context')
-_Bot = Union['Bot', 'AutoShardedBot']
-BotT = TypeVar('BotT', bound=_Bot, covariant=True)
-
 Check = Union[Callable[["Cog", "ContextT"], MaybeCoro[bool]], Callable[["ContextT"], MaybeCoro[bool]]]
 Hook = Union[Callable[["Cog", "ContextT"], Coro[Any]], Callable[["ContextT"], Coro[Any]]]
 Error = Union[Callable[["Cog", "ContextT", "CommandError"], Coro[Any]], Callable[["ContextT", "CommandError"], Coro[Any]]]
 
+ContextT = TypeVar('ContextT', bound='Context[Any]')
+BotT = TypeVar('BotT', bound=_Bot, covariant=True)
+ErrorT = TypeVar('ErrorT', bound='Error[Context[Any]]')
+HookT = TypeVar('HookT', bound='Hook[Context[Any]]')
+
 
 # This is merely a tag type to avoid circular import issues.
 # Yes, this is a terrible solution but ultimately it is the only solution.

discord/ext/commands/bot.py

@@ -151,7 +151,7 @@ class BotBase(GroupMixin[None]):
     def __init__(
         self,
         command_prefix: PrefixType[BotT],
-        help_command: Optional[HelpCommand] = _default,
+        help_command: Optional[HelpCommand[Any]] = _default,
         description: Optional[str] = None,
         **options: Any,
     ) -> None:
@@ -166,7 +166,7 @@ class BotBase(GroupMixin[None]):
         self._check_once: List[Check] = []
         self._before_invoke: Optional[CoroFunc] = None
         self._after_invoke: Optional[CoroFunc] = None
-        self._help_command: Optional[HelpCommand] = None
+        self._help_command: Optional[HelpCommand[Any]] = None
         self.description: str = inspect.cleandoc(description) if description else ''
         self.owner_id: Optional[int] = options.get('owner_id')
         self.owner_ids: Optional[Collection[int]] = options.get('owner_ids', set())
@@ -989,11 +989,11 @@ class BotBase(GroupMixin[None]):
     # help command stuff
 
     @property
-    def help_command(self) -> Optional[HelpCommand]:
+    def help_command(self) -> Optional[HelpCommand[Any]]:
         return self._help_command
 
     @help_command.setter
-    def help_command(self, value: Optional[HelpCommand]) -> None:
+    def help_command(self, value: Optional[HelpCommand[Any]]) -> None:
         if value is not None:
             if not isinstance(value, HelpCommand):
                 raise TypeError('help_command must be a subclass of HelpCommand')

discord/ext/commands/core.py

@@ -68,6 +68,8 @@ if TYPE_CHECKING:
         Check,
         Hook,
         Error,
+        ErrorT,
+        HookT,
     )
 
 
@@ -105,7 +107,6 @@ CogT = TypeVar('CogT', bound='Optional[Cog]')
 CommandT = TypeVar('CommandT', bound='Command')
 # CHT = TypeVar('CHT', bound='Check')
 GroupT = TypeVar('GroupT', bound='Group')
-FuncT = TypeVar('FuncT', bound=Callable[..., Any])
 
 if TYPE_CHECKING:
     P = ParamSpec('P')
@@ -920,7 +921,7 @@ class Command(_BaseCommand, Generic[CogT, P, T]):
             if call_hooks:
                 await self.call_after_hooks(ctx)
 
-    def error(self, coro: FuncT) -> FuncT:
+    def error(self, coro: ErrorT) -> ErrorT:
         """A decorator that registers a coroutine as a local error handler.
 
         A local error handler is an :func:`.on_command_error` event limited to
@@ -951,7 +952,7 @@ class Command(_BaseCommand, Generic[CogT, P, T]):
         """
         return hasattr(self, 'on_error')
 
-    def before_invoke(self, coro: FuncT) -> FuncT:
+    def before_invoke(self, coro: HookT) -> HookT:
         """A decorator that registers a coroutine as a pre-invoke hook.
 
         A pre-invoke hook is called directly before the command is
@@ -978,7 +979,7 @@ class Command(_BaseCommand, Generic[CogT, P, T]):
         self._before_invoke = coro
         return coro
 
-    def after_invoke(self, coro: FuncT) -> FuncT:
+    def after_invoke(self, coro: HookT) -> HookT:
         """A decorator that registers a coroutine as a post-invoke hook.
 
         A post-invoke hook is called directly after the command is
@@ -2319,7 +2320,7 @@ def max_concurrency(number: int, per: BucketType = BucketType.default, *, wait:
     return decorator  # type: ignore
 
 
-def before_invoke(coro) -> Callable[[T], T]:
+def before_invoke(coro: Hook[ContextT]) -> Callable[[T], T]:
     """A decorator that registers a coroutine as a pre-invoke hook.
 
     This allows you to refer to one before invoke hook for several commands that
@@ -2367,7 +2368,7 @@ def before_invoke(coro) -> Callable[[T], T]:
     return decorator  # type: ignore
 
 
-def after_invoke(coro) -> Callable[[T], T]:
+def after_invoke(coro: Hook[ContextT]) -> Callable[[T], T]:
     """A decorator that registers a coroutine as a post-invoke hook.
 
     This allows you to refer to one after invoke hook for several commands that

discord/ext/commands/help.py

@@ -262,6 +262,7 @@ class HelpCommand(HelpCommandCommand, Generic[ContextT]):
     ) -> None:
         self.show_hidden: bool = show_hidden
         self.verify_checks: bool = verify_checks
+        self.command_attrs: Dict[str, Any]
         self.command_attrs = attrs = command_attrs if command_attrs is not MISSING else {}
         attrs.setdefault('name', 'help')
         attrs.setdefault('help', 'Shows this message')