Allow Closing to detect dependent resources (ets-labs#636)

Author: StummeJ

src/dependency_injector/wiring.py

@@ -593,6 +593,22 @@ def _fetch_reference_injections(  # noqa: C901
     return injections, closing
 
 
+def _locate_dependent_closing_args(provider: providers.Provider) -> dict[str, providers.Provider]:
+    if not hasattr(provider, "args"):
+        return {}
+
+    closing_deps = {}
+    for arg in provider.args:
+        if not isinstance(arg, providers.Provider) or not hasattr(arg, "args"):
+            continue
+
+        if not arg.args and isinstance(arg, providers.Resource):
+            return {str(id(arg)): arg}
+        else:
+            closing_deps += _locate_dependent_closing_args(arg)
+    return closing_deps
+
+
 def _bind_injections(fn: Callable[..., Any], providers_map: ProvidersMap) -> None:
     patched_callable = _patched_registry.get_callable(fn)
     if patched_callable is None:
@@ -614,6 +630,9 @@ def _bind_injections(fn: Callable[..., Any], providers_map: ProvidersMap) -> Non
 
         if injection in patched_callable.reference_closing:
             patched_callable.add_closing(injection, provider)
+            deps = _locate_dependent_closing_args(provider)
+            for key, dep in deps.items():
+                patched_callable.add_closing(key, dep)
 
 
 def _unbind_injections(fn: Callable[..., Any]) -> None:

tests/unit/samples/wiringstringids/resourceclosing.py

@@ -20,6 +20,11 @@ def shutdown(cls):
         cls.shutdown_counter += 1
 
 
+class FactoryService:
+    def __init__(self, service: Service):
+        self.service = service
+
+
 def init_service():
     service = Service()
     service.init()
@@ -30,8 +35,14 @@ def init_service():
 class Container(containers.DeclarativeContainer):
 
     service = providers.Resource(init_service)
+    factory_service = providers.Factory(FactoryService, service)
 
 
 @inject
 def test_function(service: Service = Closing[Provide["service"]]):
     return service
+
+
+@inject
+def test_function_dependency(factory: FactoryService = Closing[Provide["factory_service"]]):
+    return factory

tests/unit/wiring/string_ids/test_main_py36.py

@@ -289,6 +289,23 @@ def test_closing_resource():
     assert result_1 is not result_2
 
 
+@mark.usefixtures("resourceclosing_container")
+def test_closing_dependency_resource():
+    resourceclosing.Service.reset_counter()
+
+    result_1 = resourceclosing.test_function_dependency()
+    assert isinstance(result_1, resourceclosing.FactoryService)
+    assert result_1.service.init_counter == 1
+    assert result_1.service.shutdown_counter == 1
+
+    result_2 = resourceclosing.test_function_dependency()
+    assert isinstance(result_2, resourceclosing.FactoryService)
+    assert result_2.service.init_counter == 2
+    assert result_2.service.shutdown_counter == 2
+
+    assert result_1 is not result_2
+
+
 @mark.usefixtures("resourceclosing_container")
 def test_closing_resource_bypass_marker_injection():
     resourceclosing.Service.reset_counter()