Add types module for explicit provider typing

src/dependency_injector/providers.pyi

@@ -14,6 +14,9 @@ from typing import (
     Coroutine as _Coroutine,
 )
 
+from .types import Provider as _Provider
+
+
 Injection = Any
 T = TypeVar('T')
 
@@ -24,7 +27,7 @@ class OverridingContext:
     def __exit__(self, *_: Any) -> None: ...
 
 
-class Provider:
+class Provider(_Provider):
     def __init__(self) -> None: ...
     def __call__(self, *args: Injection, **kwargs: Injection) -> Any: ...
     def __deepcopy__(self, memo: Optional[Dict[str, Any]]) -> Provider: ...

src/dependency_injector/types.py

@@ -0,0 +1,9 @@
+from typing import TypeVar, Generic, Any
+
+
+Injection = Any
+T = TypeVar('T')
+
+
+class Provider(Generic[T]):
+    def __call__(self, *args: Injection, **kwargs: Injection) -> T: ...

tests/typing/factory.py

@@ -1,6 +1,6 @@
 from typing import Tuple, Any, Dict
 
-from dependency_injector import providers
+from dependency_injector import providers, types
 
 
 class Animal:
@@ -62,3 +62,7 @@ provider9 = providers.FactoryAggregate(
 factory_a_9: providers.Factory = provider9.a
 factory_b_9: providers.Factory = provider9.b
 val9: Any = provider9('a')
+
+# Test 10: to check the explicit typing
+factory10: types.Provider[Animal] = providers.Factory(Cat)
+animal10: Animal = factory10()