Types: don't leave generic types without a parameter (#2401)

CHANGES.rst

@@ -5,6 +5,9 @@ Version 8.1.4
 
 Unreleased
 
+-   Improve type hinting for decorators and give all generic types parameters.
+    :issue:`2398`
+
 
 Version 8.1.3
 -------------

setup.cfg

@@ -71,6 +71,9 @@ ignore =
     W503
     # zip with strict=, requires python >= 3.10
     B905
+    # string formatting opinion, B028 renamed to B907
+    B028
+    B907
 # up to 88 allowed by bugbear B950
 max-line-length = 80
 per-file-ignores =
@@ -85,6 +88,7 @@ disallow_subclassing_any = True
 disallow_untyped_calls = True
 disallow_untyped_defs = True
 disallow_incomplete_defs = True
+disallow_any_generics = True
 check_untyped_defs = True
 no_implicit_optional = True
 local_partial_types = True

src/click/_compat.py

@@ -50,7 +50,7 @@ def is_ascii_encoding(encoding: str) -> bool:
         return False
 
 
-def get_best_encoding(stream: t.IO) -> str:
+def get_best_encoding(stream: t.IO[t.Any]) -> str:
     """Returns the default stream encoding if not found."""
     rv = getattr(stream, "encoding", None) or sys.getdefaultencoding()
     if is_ascii_encoding(rv):
@@ -153,7 +153,7 @@ def seekable(self) -> bool:
         return True
 
 
-def _is_binary_reader(stream: t.IO, default: bool = False) -> bool:
+def _is_binary_reader(stream: t.IO[t.Any], default: bool = False) -> bool:
     try:
         return isinstance(stream.read(0), bytes)
     except Exception:
@@ -162,7 +162,7 @@ def _is_binary_reader(stream: t.IO, default: bool = False) -> bool:
         # closed.  In this case, we assume the default.
 
 
-def _is_binary_writer(stream: t.IO, default: bool = False) -> bool:
+def _is_binary_writer(stream: t.IO[t.Any], default: bool = False) -> bool:
     try:
         stream.write(b"")
     except Exception:
@@ -175,7 +175,7 @@ def _is_binary_writer(stream: t.IO, default: bool = False) -> bool:
     return True
 
 
-def _find_binary_reader(stream: t.IO) -> t.Optional[t.BinaryIO]:
+def _find_binary_reader(stream: t.IO[t.Any]) -> t.Optional[t.BinaryIO]:
     # We need to figure out if the given stream is already binary.
     # This can happen because the official docs recommend detaching
     # the streams to get binary streams.  Some code might do this, so
@@ -193,7 +193,7 @@ def _find_binary_reader(stream: t.IO) -> t.Optional[t.BinaryIO]:
     return None
 
 
-def _find_binary_writer(stream: t.IO) -> t.Optional[t.BinaryIO]:
+def _find_binary_writer(stream: t.IO[t.Any]) -> t.Optional[t.BinaryIO]:
     # We need to figure out if the given stream is already binary.
     # This can happen because the official docs recommend detaching
     # the streams to get binary streams.  Some code might do this, so
@@ -241,11 +241,11 @@ def _is_compatible_text_stream(
 
 
 def _force_correct_text_stream(
-    text_stream: t.IO,
+    text_stream: t.IO[t.Any],
     encoding: t.Optional[str],
     errors: t.Optional[str],
-    is_binary: t.Callable[[t.IO, bool], bool],
-    find_binary: t.Callable[[t.IO], t.Optional[t.BinaryIO]],
+    is_binary: t.Callable[[t.IO[t.Any], bool], bool],
+    find_binary: t.Callable[[t.IO[t.Any]], t.Optional[t.BinaryIO]],
     force_readable: bool = False,
     force_writable: bool = False,
 ) -> t.TextIO:
@@ -287,7 +287,7 @@ def _force_correct_text_stream(
 
 
 def _force_correct_text_reader(
-    text_reader: t.IO,
+    text_reader: t.IO[t.Any],
     encoding: t.Optional[str],
     errors: t.Optional[str],
     force_readable: bool = False,
@@ -303,7 +303,7 @@ def _force_correct_text_reader(
 
 
 def _force_correct_text_writer(
-    text_writer: t.IO,
+    text_writer: t.IO[t.Any],
     encoding: t.Optional[str],
     errors: t.Optional[str],
     force_writable: bool = False,
@@ -367,11 +367,11 @@ def get_text_stderr(
 
 
 def _wrap_io_open(
-    file: t.Union[str, os.PathLike, int],
+    file: t.Union[str, "os.PathLike[t.AnyStr]", int],
     mode: str,
     encoding: t.Optional[str],
     errors: t.Optional[str],
-) -> t.IO:
+) -> t.IO[t.Any]:
     """Handles not passing ``encoding`` and ``errors`` in binary mode."""
     if "b" in mode:
         return open(file, mode)
@@ -385,7 +385,7 @@ def open_stream(
     encoding: t.Optional[str] = None,
     errors: t.Optional[str] = "strict",
     atomic: bool = False,
-) -> t.Tuple[t.IO, bool]:
+) -> t.Tuple[t.IO[t.Any], bool]:
     binary = "b" in mode
 
     # Standard streams first. These are simple because they ignore the
@@ -456,11 +456,11 @@ def open_stream(
 
     f = _wrap_io_open(fd, mode, encoding, errors)
     af = _AtomicFile(f, tmp_filename, os.path.realpath(filename))
-    return t.cast(t.IO, af), True
+    return t.cast(t.IO[t.Any], af), True
 
 
 class _AtomicFile:
-    def __init__(self, f: t.IO, tmp_filename: str, real_filename: str) -> None:
+    def __init__(self, f: t.IO[t.Any], tmp_filename: str, real_filename: str) -> None:
         self._f = f
         self._tmp_filename = tmp_filename
         self._real_filename = real_filename
@@ -483,7 +483,7 @@ def __getattr__(self, name: str) -> t.Any:
     def __enter__(self) -> "_AtomicFile":
         return self
 
-    def __exit__(self, exc_type, exc_value, tb):  # type: ignore
+    def __exit__(self, exc_type: t.Optional[t.Type[BaseException]], *_: t.Any) -> None:
         self.close(delete=exc_type is not None)
 
     def __repr__(self) -> str:
@@ -494,15 +494,15 @@ def strip_ansi(value: str) -> str:
     return _ansi_re.sub("", value)
 
 
-def _is_jupyter_kernel_output(stream: t.IO) -> bool:
+def _is_jupyter_kernel_output(stream: t.IO[t.Any]) -> bool:
     while isinstance(stream, (_FixupStream, _NonClosingTextIOWrapper)):
         stream = stream._stream
 
     return stream.__class__.__module__.startswith("ipykernel.")
 
 
 def should_strip_ansi(
-    stream: t.Optional[t.IO] = None, color: t.Optional[bool] = None
+    stream: t.Optional[t.IO[t.Any]] = None, color: t.Optional[bool] = None
 ) -> bool:
     if color is None:
         if stream is None:
@@ -576,7 +576,7 @@ def term_len(x: str) -> int:
     return len(strip_ansi(x))
 
 
-def isatty(stream: t.IO) -> bool:
+def isatty(stream: t.IO[t.Any]) -> bool:
     try:
         return stream.isatty()
     except Exception:

src/click/_termui_impl.py

@@ -93,12 +93,12 @@ def __init__(
         self.is_hidden = not isatty(self.file)
         self._last_line: t.Optional[str] = None
 
-    def __enter__(self) -> "ProgressBar":
+    def __enter__(self) -> "ProgressBar[V]":
         self.entered = True
         self.render_progress()
         return self
 
-    def __exit__(self, exc_type, exc_value, tb):  # type: ignore
+    def __exit__(self, *_: t.Any) -> None:
         self.render_finish()
 
     def __iter__(self) -> t.Iterator[V]:

src/click/core.py

@@ -455,7 +455,7 @@ def __enter__(self) -> "Context":
         push_context(self)
         return self
 
-    def __exit__(self, exc_type, exc_value, tb):  # type: ignore
+    def __exit__(self, *_: t.Any) -> None:
         self._depth -= 1
         if self._depth == 0:
             self.close()
@@ -706,12 +706,30 @@ def _make_sub_context(self, command: "Command") -> "Context":
         """
         return type(self)(command, info_name=command.name, parent=self)
 
+    @t.overload
+    def invoke(
+        __self,  # noqa: B902
+        __callback: "t.Callable[..., V]",
+        *args: t.Any,
+        **kwargs: t.Any,
+    ) -> V:
+        ...
+
+    @t.overload
     def invoke(
         __self,  # noqa: B902
-        __callback: t.Union["Command", t.Callable[..., t.Any]],
+        __callback: "Command",
         *args: t.Any,
         **kwargs: t.Any,
     ) -> t.Any:
+        ...
+
+    def invoke(
+        __self,  # noqa: B902
+        __callback: t.Union["Command", "t.Callable[..., V]"],
+        *args: t.Any,
+        **kwargs: t.Any,
+    ) -> t.Union[t.Any, V]:
         """Invokes a command callback in exactly the way it expects.  There
         are two ways to invoke this method:
 
@@ -739,7 +757,7 @@ def invoke(
                     "The given command does not have a callback that can be invoked."
                 )
             else:
-                __callback = other_cmd.callback
+                __callback = t.cast("t.Callable[..., V]", other_cmd.callback)
 
             ctx = __self._make_sub_context(other_cmd)
 
@@ -1841,7 +1859,7 @@ def command(
         if self.command_class and kwargs.get("cls") is None:
             kwargs["cls"] = self.command_class
 
-        func: t.Optional[t.Callable] = None
+        func: t.Optional[t.Callable[..., t.Any]] = None
 
         if args and callable(args[0]):
             assert (
@@ -1889,7 +1907,7 @@ def group(
         """
         from .decorators import group
 
-        func: t.Optional[t.Callable] = None
+        func: t.Optional[t.Callable[..., t.Any]] = None
 
         if args and callable(args[0]):
             assert (
@@ -2260,7 +2278,7 @@ def type_cast_value(self, ctx: Context, value: t.Any) -> t.Any:
         if value is None:
             return () if self.multiple or self.nargs == -1 else None
 
-        def check_iter(value: t.Any) -> t.Iterator:
+        def check_iter(value: t.Any) -> t.Iterator[t.Any]:
             try:
                 return _check_iter(value)
             except TypeError:
@@ -2277,12 +2295,12 @@ def check_iter(value: t.Any) -> t.Iterator:
             )
         elif self.nargs == -1:
 
-            def convert(value: t.Any) -> t.Tuple:
+            def convert(value: t.Any) -> t.Tuple[t.Any, ...]:
                 return tuple(self.type(x, self, ctx) for x in check_iter(value))
 
         else:  # nargs > 1
 
-            def convert(value: t.Any) -> t.Tuple:
+            def convert(value: t.Any) -> t.Tuple[t.Any, ...]:
                 value = tuple(check_iter(value))
 
                 if len(value) != self.nargs:
@@ -2817,7 +2835,7 @@ def get_default(
         if self.is_flag and not self.is_bool_flag:
             for param in ctx.command.params:
                 if param.name == self.name and param.default:
-                    return param.flag_value  # type: ignore
+                    return t.cast(Option, param).flag_value
 
             return None