Injection of class instances as self

src/dishka/integrations/base.py

@@ -1,3 +1,4 @@
+import inspect
 from collections.abc import Awaitable, Callable, Sequence
 from inspect import (
     Parameter,
@@ -96,9 +97,15 @@ def wrap_injection(
     func_signature = signature(func)
 
     dependencies = {}
-    for name, param in func_signature.parameters.items():
-        hint = hints.get(name, Any)
-        dep = parse_dependency(param, hint)
+    for index, (name, param) in enumerate(func_signature.parameters.items()):
+        if name == "self" and index == 0:
+            # If it's a method in a class, by the time this is run the class
+            # hasn't been created yet, and inspection would fail. So,
+            # postpone it.
+            dep = DependencyKey(func, DEFAULT_COMPONENT)
+        else:
+            hint = hints.get(name, Any)
+            dep = parse_dependency(param, hint)
         if dep is None:
             continue
         dependencies[name] = dep
@@ -185,6 +192,11 @@ async def auto_injected_func(*args: P.args, **kwargs: P.kwargs) -> T:
             container = container_getter(args, kwargs)
             for param in additional_params:
                 kwargs.pop(param.name)
+
+            if (dep := dependencies.get("self")) and dep.type_hint == func:
+                klass = inspect._findclass(dep.type_hint)  # noqa: SLF001
+                dependencies["self"] = DependencyKey(klass, dep.component)
+
             solved = {
                 name: await container.get(
                     dep.type_hint, component=dep.component,
@@ -198,6 +210,11 @@ async def auto_injected_func(*args: P.args, **kwargs: P.kwargs) -> T:
             container = container_getter(args, kwargs)
             for param in additional_params:
                 kwargs.pop(param.name)
+
+            if (dep := dependencies.get("self")) and dep.type_hint == func:
+                klass = inspect._findclass(dep.type_hint)  # noqa: SLF001
+                dependencies["self"] = DependencyKey(klass, dep.component)
+
             solved = {
                 name: await container.get(
                     dep.type_hint, component=dep.component,

tests/integrations/fastapi/test_fastapi.py

@@ -7,7 +7,7 @@
 from asgi_lifespan import LifespanManager
 from fastapi.testclient import TestClient
 
-from dishka import make_async_container
+from dishka import Scope, make_async_container, provide
 from dishka.integrations.fastapi import (
     DishkaRoute,
     FromDishka,
@@ -18,6 +18,7 @@
     APP_DEP_VALUE,
     REQUEST_DEP_VALUE,
     AppDep,
+    AppMock,
     AppProvider,
     RequestDep,
 )
@@ -68,6 +69,44 @@ async def test_app_dependency(app_provider: AppProvider, app_factory):
     app_provider.app_released.assert_called()
 
 
+class Wrapper:
+    def __init__(
+        self,
+        a: AppDep,
+        app_mock: AppMock,
+    ):
+        self.a = a
+        self.app_mock = app_mock
+
+    async def get_with_app(
+            self,
+            a: FromDishka[AppDep],
+            app_mock: FromDishka[AppMock],
+    ) -> None:
+        assert self.a == a
+        assert self.app_mock == app_mock
+        app_mock(a)
+
+
+class LocalProvider(AppProvider):
+    scope = Scope.APP
+
+    wrapper = provide(Wrapper)
+
+
+@pytest.mark.parametrize("app_factory", [
+    dishka_app, dishka_auto_app,
+])
+@pytest.mark.asyncio
+async def test_app_dependency_class(app_factory):
+    app_provider = LocalProvider()
+    async with app_factory(Wrapper.get_with_app, app_provider) as client:
+        client.get("/")
+        app_provider.app_mock.assert_called_with(APP_DEP_VALUE)
+        app_provider.app_released.assert_not_called()
+    app_provider.app_released.assert_called()
+
+
 async def get_with_request(
         a: FromDishka[RequestDep],
         mock: FromDishka[Mock],