Testing

django-autowired ships with three testing strategies, from pure to full-integration.

1. Pure unit tests (no container)

For testing a single class, don't involve the container. Pass mocks directly into the constructor:

from myapp.services.order_service import OrderService

def test_places_order():
    svc = OrderService(
        payment_gateway=FakePaymentGateway(),
        inventory=FakeInventory(),
    )
    result = svc.place("SKU-123")
    assert result.status == "confirmed"

This is the fastest, most isolated style. Prefer it for domain logic.

2. Integration tests with autowired_container

When you need the real wiring, use the pytest fixture + markers:

import pytest
from django_autowired import container
from myapp.services.order_service import OrderService

@pytest.mark.autowired_packages(["myapp.services", "myapp.adapters"])
@pytest.mark.autowired_backend("injector")
def test_full_wiring(autowired_container):
    svc = container.get(OrderService)
    assert svc is not None

The fixture initializes the container from your markers, yields the backend, and resets on teardown.

3. Partial integration with build_container

When you want real wiring plus selective overrides, use the build_container factory:

def test_order_with_fake_gateway(build_container):
    build_container(
        packages=["myapp.services", "myapp.adapters"],
        overrides={IPaymentGateway: FakePaymentGateway},
    )
    svc = container.get(OrderService)
    ...

Non-pytest: container_context

For scripts or doctests:

from django_autowired.testing import container_context

with container_context(
    packages=["myapp.services"],
    overrides={IPaymentGateway: FakePaymentGateway},
):
    svc = container.get(OrderService)
    ...
# container is reset here

InMemoryOverrideModule (injector-specific)

When you need overrides applied during initialization (not after), wrap them in an injector.Module:

from django_autowired.testing import InMemoryOverrideModule

container.initialize(
    packages=["myapp"],
    extra_modules=[InMemoryOverrideModule({IPaymentGateway: FakePaymentGateway})],
)

Anti-patterns

Never call container.get() inside domain code.

# BAD
class OrderService:
    def place(self, sku: str):
        gateway = container.get(IPaymentGateway)   # service locator — avoid
        ...

# GOOD
class OrderService:
    def __init__(self, gateway: IPaymentGateway) -> None:
        self._gateway = gateway

Catch this in code review: grep for container.get in non-framework code. If you see it outside of views.py, tasks.py, or similar entrypoints, it's a smell.