Add stubs for the configuration options

src/dependency_injector/providers.pyi

@@ -117,6 +117,39 @@ class CoroutineDelegate(Delegate):
     def __init__(self, coroutine: Coroutine) -> None: ...
 
 
+class ConfigurationOption(Provider):
+    UNDEFINED: object
+    def __init__(self, name: str, root: Configuration) -> None: ...
+    def __call__(self, *args: Injection, **kwargs: Injection) -> Any: ...
+    def __getattr__(self, item: str) -> ConfigurationOption: ...
+    def __getitem__(self, item: str) -> ConfigurationOption: ...
+    def get_name(self) -> str: ...
+    def as_int(self) -> Callable[int]: ...
+    def as_float(self) -> Callable[float]: ...
+    def as_(self, callback: _Callable[..., T], *args: Injection, **kwargs: Injection) -> Callable[T]: ...
+    def update(self, value: Any) -> None: ...
+    def from_ini(self, filepath: str) -> None: ...
+    def from_yaml(self, filepath: str) -> None: ...
+    def from_dict(self, options: Dict[str, Any]) -> None: ...
+    def from_env(self, name: str, default: Optional[Any] = None) -> None: ...
+
+
+class Configuration(Object):
+    DEFAULT_NAME: str = 'config'
+    def __init__(self, name: str = DEFAULT_NAME, default: Optional[Any] = None) -> None: ...
+    def __getattr__(self, item: str) -> ConfigurationOption: ...
+    def __getitem__(self, item: str) -> ConfigurationOption: ...
+    def get_name(self) -> str: ...
+    def get(self, selector: str) -> Any: ...
+    def set(self, selector: str, value: Any) -> OverridingContext: ...
+    def reset_cache(self) -> None: ...
+    def update(self, value: Any) -> None: ...
+    def from_ini(self, filepath: str) -> None: ...
+    def from_yaml(self, filepath: str) -> None: ...
+    def from_dict(self, options: Dict[str, Any]) -> None: ...
+    def from_env(self, name: str, default: Optional[Any] = None) -> None: ...
+
+
 class Factory(Provider, Generic[T]):
     provided_type: Optional[Type]
     def __init__(self, provides: _Callable[..., T], *args: Injection, **kwargs: Injection) -> None: ...

tests/typing/configuration.py

@@ -0,0 +1,19 @@
+from dependency_injector import providers
+
+
+# Test 1: to check the getattr
+config1 = providers.Configuration()
+provider1 = providers.Factory(dict, a=config1.a)
+
+# Test 2: to check the from_*() method
+config2 = providers.Configuration()
+config2.from_dict({})
+config2.from_ini('config.ini')
+config2.from_yaml('config.yml')
+config2.from_env('ENV', 'default')
+
+# Test 3: to check as_*() methods
+config3 = providers.Configuration()
+int3: providers.Callable[int] = config3.option.as_int()
+float3: providers.Callable[float] = config3.option.as_float()
+int3_custom: providers.Callable[int] = config3.option.as_(int)