Add with support for container.override_providers() (ets-labs#517)

* Add implementation, tests, and typing stub

* Update documentation

* Update changelog

Author: rmk135

docs/containers/declarative.rst

@@ -34,10 +34,39 @@ Injections in the declarative container are done the usual way:
    :language: python
    :lines: 3-
 
-You can override the container providers when you create the container instance:
+You can override container providers while creating a container instance:
 
 .. literalinclude:: ../../examples/containers/declarative_override_providers.py
    :language: python
    :lines: 3-
+   :emphasize-lines: 13
+
+Alternatively, you can call ``container.override_providers()`` method when the container instance
+already exists:
+
+.. code-block:: python
+   :emphasize-lines: 3
+
+   container = Container()
+
+   container.override_providers(foo=mock.Mock(Foo), bar=mock.Mock(Bar))
+
+   assert isinstance(container.foo(), mock.Mock)
+   assert isinstance(container.bar(), mock.Mock)
+
+You can also use ``container.override_providers()`` with a context manager to reset
+provided overriding after the context is closed:
+
+.. code-block:: python
+   :emphasize-lines: 3
+
+   container = Container()
+
+   with container.override_providers(foo=mock.Mock(Foo), bar=mock.Mock(Bar)):
+       assert isinstance(container.foo(), mock.Mock)
+       assert isinstance(container.bar(), mock.Mock)
+
+   assert isinstance(container.foo(), Foo)
+   assert isinstance(container.bar(), Bar)
 
 .. disqus::

docs/main/changelog.rst

@@ -12,6 +12,7 @@ Develop
 - Improve wiring with adding importing modules and packages from a string
   ``container.wire(modules=["yourapp.module1"])``.
 - Add container wiring configuration ``wiring_config = containers.WiringConfiguration()``.
+- Add support of ``with`` statement for ``container.override_providers()`` method.
 - Update documentation and fix typos.
 
 4.36.2

src/dependency_injector/containers.c

@@ -50,7 +50,7 @@ class Container:
     def set_providers(self, **providers: Provider): ...
     def set_provider(self, name: str, provider: Provider) -> None: ...
     def override(self, overriding: C_Base) -> None: ...
-    def override_providers(self, **overriding_providers: Union[Provider, Any]) -> None: ...
+    def override_providers(self, **overriding_providers: Union[Provider, Any]) -> ProvidersOverridingContext[C_Base]: ...
     def reset_last_overriding(self) -> None: ...
     def reset_override(self) -> None: ...
     def is_auto_wiring_enabled(self) -> bool: ...
@@ -90,6 +90,12 @@ class DeclarativeContainer(Container):
     def __init__(self, **overriding_providers: Union[Provider, Any]) -> None: ...
 
 
+class ProvidersOverridingContext(Generic[T]):
+    def __init__(self, container: T, overridden_providers: Iterable[Union[Provider, Any]]) -> None: ...
+    def __enter__(self) -> T: ...
+    def __exit__(self, *_: Any) -> None: ...
+
+
 class SingletonResetContext(Generic[T]):
     def __init__(self, container: T): ...
     def __enter__(self) -> T: ...

src/dependency_injector/containers.pyi

@@ -240,9 +240,12 @@ class DynamicContainer(Container):
 
         :rtype: None
         """
+        overridden_providers = []
         for name, overriding_provider in six.iteritems(overriding_providers):
             container_provider = getattr(self, name)
             container_provider.override(overriding_provider)
+            overridden_providers.append(container_provider)
+        return ProvidersOverridingContext(self, overridden_providers)
 
     def reset_last_overriding(self):
         """Reset last overriding provider for each container providers.
@@ -784,6 +787,21 @@ class SingletonResetContext:
         self._container.reset_singletons()
 
 
+
+class ProvidersOverridingContext:
+
+    def __init__(self, container, overridden_providers):
+        self._container = container
+        self._overridden_providers = overridden_providers
+
+    def __enter__(self):
+        return self._container
+
+    def __exit__(self, *_):
+        for provider in self._overridden_providers:
+            provider.reset_last_overriding()
+
+
 def override(object container):
     """:py:class:`DeclarativeContainer` overriding decorator.
 

src/dependency_injector/containers.pyx

@@ -58,9 +58,11 @@ class Container6(containers.DeclarativeContainer):
 container6: containers.Container = Container6()
 
 
-# Test 7: to override()
+# Test 7: to override_providers()
 class Container7(containers.DeclarativeContainer):
     provider = providers.Factory(str)
 
 container7 = Container7()
 container7.override_providers(provider="new_value")
+with container7.override_providers(a=providers.Provider()):
+    ...

tests/typing/declarative_container.py

@@ -14,6 +14,8 @@
 # Test 3: to check override_providers()
 container3 = containers.DynamicContainer()
 container3.override_providers(a=providers.Provider())
+with container3.override_providers(a=providers.Provider()):
+    ...
 
 # Test 4: to check set_providers()
 container4 = containers.DynamicContainer()

tests/typing/dynamic_container.py

@@ -134,6 +134,19 @@ def test_override_providers(self):
         self.assertIs(container_a.p11.last_overriding, p1)
         self.assertIs(container_a.p12.last_overriding, p2)
 
+    def test_override_providers_context_manager(self):
+        p1 = providers.Provider()
+        p2 = providers.Provider()
+        container_a = ContainerA()
+
+        with container_a.override_providers(p11=p1, p12=p2) as container:
+            self.assertIs(container, container_a)
+            self.assertIs(container_a.p11.last_overriding, p1)
+            self.assertIs(container_a.p12.last_overriding, p2)
+
+        self.assertIsNone(container_a.p11.last_overriding)
+        self.assertIsNone(container_a.p12.last_overriding)
+
     def test_override_providers_with_unknown_provider(self):
         container_a = ContainerA()