fixed covariant mapping value type used in overload

Author: randolf-scholz

stdlib/collections/__init__.pyi

@@ -106,9 +106,7 @@ class UserDict(MutableMapping[_KT, _VT]):
     def __ior__(self, other: Iterable[tuple[_KT, _VT]]) -> Self: ...
     if sys.version_info >= (3, 12):
         @overload
-        def get(self, key: _KT, default: None = None) -> _VT | None: ...
-        @overload
-        def get(self, key: _KT, default: _VT) -> _VT: ...
+        def get(self, key: _KT) -> _VT | None: ...
         @overload
         def get(self, key: _KT, default: _T) -> _VT | _T: ...
 
@@ -458,9 +456,7 @@ class ChainMap(MutableMapping[_KT, _VT]):
     def __len__(self) -> int: ...
     def __contains__(self, key: object) -> bool: ...
     @overload
-    def get(self, key: _KT, default: None = None) -> _VT | None: ...
-    @overload
-    def get(self, key: _KT, default: _VT) -> _VT: ...
+    def get(self, key: _KT) -> _VT | None: ...
     @overload
     def get(self, key: _KT, default: _T) -> _VT | _T: ...
     def __missing__(self, key: _KT) -> _VT: ...  # undocumented

stdlib/os/__init__.pyi

@@ -711,9 +711,7 @@ class _Environ(MutableMapping[AnyStr, AnyStr], Generic[AnyStr]):
         decodevalue: _EnvironCodeFunc[AnyStr],
     ) -> None: ...
     @overload
-    def get(self, key: AnyStr, default: None = None) -> AnyStr | None: ...
-    @overload
-    def get(self, key: AnyStr, default: AnyStr) -> AnyStr: ...
+    def get(self, key: AnyStr) -> AnyStr | None: ...
     @overload
     def get(self, key: AnyStr, default: _T) -> AnyStr | _T: ...
     @overload

stdlib/types.pyi

@@ -323,8 +323,6 @@ class MappingProxyType(Mapping[_KT_co, _VT_co]):  # type: ignore[type-var]  # py
     @overload
     def get(self, key: _KT_co, /) -> _VT_co | None: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues] # Covariant type as parameter
     @overload
-    def get(self, key: _KT_co, default: _VT_co, /) -> _VT_co: ...  # type: ignore[misc] # pyright: ignore[reportGeneralTypeIssues] # Covariant type as parameter
-    @overload
     def get(self, key: _KT_co, default: _T2, /) -> _VT_co | _T2: ...  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues] # Covariant type as parameter
     def __class_getitem__(cls, item: Any, /) -> GenericAlias: ...
     def __reversed__(self) -> Iterator[_KT_co]: ...

stdlib/typing.pyi

@@ -785,8 +785,6 @@ class Mapping(Collection[_KT], Generic[_KT, _VT_co]):
     @overload
     def get(self, key: _KT, /) -> _VT_co | None: ...
     @overload
-    def get(self, key: _KT, default: _VT_co, /) -> _VT_co: ...  # type: ignore[misc] # pyright: ignore[reportGeneralTypeIssues] # Covariant type as parameter
-    @overload
     def get(self, key: _KT, default: _T, /) -> _VT_co | _T: ...
     def items(self) -> ItemsView[_KT, _VT_co]: ...
     def keys(self) -> KeysView[_KT]: ...

stdlib/weakref.pyi

@@ -99,9 +99,7 @@ class WeakValueDictionary(MutableMapping[_KT, _VT]):
     __copy__ = copy
     def __deepcopy__(self, memo: Any) -> Self: ...
     @overload
-    def get(self, key: _KT, default: None = None) -> _VT | None: ...
-    @overload
-    def get(self, key: _KT, default: _VT) -> _VT: ...
+    def get(self, key: _KT) -> _VT | None: ...
     @overload
     def get(self, key: _KT, default: _T) -> _VT | _T: ...
     # These are incompatible with Mapping
@@ -152,9 +150,7 @@ class WeakKeyDictionary(MutableMapping[_KT, _VT]):
     __copy__ = copy
     def __deepcopy__(self, memo: Any) -> Self: ...
     @overload
-    def get(self, key: _KT, default: None = None) -> _VT | None: ...
-    @overload
-    def get(self, key: _KT, default: _VT) -> _VT: ...
+    def get(self, key: _KT) -> _VT | None: ...
     @overload
     def get(self, key: _KT, default: _T) -> _VT | _T: ...
     # These are incompatible with Mapping