| name | specx-tests |
| description | Add or refine tests for Specx Python services. Use when creating unit tests for use cases/services, integration tests for FastAPI controllers or infrastructure adapters, e2e smoke tests, architecture import guardrails, DI override tests, pytest fixtures, or coverage and boundary checks. |
Specx Tests
Use this skill when behavior, wiring, or architecture boundaries need tests.
Read references/testing.md before creating test files.
Test Layers
tests/_support/: generic clients, DB helpers, and shared integration
helpers only. This is not a test suite and does not hold project-specific
doubles.
tests/unit/: core services, use cases, and capabilities resolved from a
fresh application container returned by the project's get_container().
tests/integration/: real internal graph tests. Core use-case integration
tests call resolved use cases against the transactional DB; delivery
integration tests exercise HTTP mapping; migrations prove Alembic behavior.
tests/e2e/: optional whole-app smoke flows.
tests/guardrails/: optional programmatic
specx.testing.architecture.assert_specx_architecture wrappers for genuinely
project-specific extra rules. Standard packaged rules run through
uv run specx check.
Rules
- Test behavior and boundaries, not implementation ceremony.
- Required generated coverage is currently scoped to core services, use cases,
and capabilities.
- Mirror source module paths directly with flat test files, for example
tests/unit/core/tasks/services/test_title_service.py.
- Do not create per-target test folders,
harness.py, target factories, or
target harnesses.
tests/unit/conftest.py owns the fresh real-app Container fixture for unit
tests and any project-wide test overrides. tests/integration/conftest.py
owns the transactional DB-backed container fixture for integration tests.
- Test functions receive
container, register any scenario-specific overrides
before resolution, then call container.resolve(Target).
- If a complete replacement is needed by every test in one module, a
module-local
container fixture may register it before returning the
container.
- Keep one-off class-based test doubles in the
test_*.py module that uses
them. When the same double is reused by multiple unit modules, put it in a
mirrored
tests/unit/core/<scope>/{capabilities,gateways,repositories}/fake_<source_module>.py
file.
- Do not create
tests/_support/fakes, tests/**/_fakes.py, generic
_scenarios.py, fake modules outside those mirrored unit port/capability
packages, or double classes in conftest.py.
- Use
MagicMock or AsyncMock inline in the test function when only one
behavior needs to be changed for that scenario. Prefer autospeccing when
call signatures matter and spec_set when unexpected attributes must fail.
- Unit tests replace external IO, time, randomness, network, Redis, database,
and framework resources with local doubles or inline mocks.
- Integration tests use the real internal app graph. Do not mock internal use
cases, services, or capabilities; stub only external systems when needed.
- Add core use-case integration tests under
tests/integration/core/... for
use cases that inject a UoW manager; delivery tests should own HTTP mapping,
not be the only persistence proof.
- Persistence integration tests use the production database family when
dialect behavior matters. A rollback harness may not replace isolated
commit-visible tests for locking, concurrency, isolation, or after-commit
behavior.
- Core health tests cover required-dependency readiness and any reusable probe
services and use cases.
Delivery probe tests cover
/healthz and /readyz as operational endpoints,
not versioned business API routes. /healthz must prove a lightweight
process response only; /readyz must prove required infrastructure readiness,
including a real bounded DB check for SQLAlchemy services.
- Probe route tests assert
Cache-Control: no-store, readiness failure returns
503, probe routes are excluded from OpenAPI, and legacy /api/v1/health is
absent when replacing old generated health endpoints.
- Unit-test logging configurators by overriding logging settings,
monkeypatching
logging.config.dictConfig, and asserting the generated
stdlib config. Use caplog only when a log record is meaningful behavior.
- Unit-test FastAPI lifecycle managers by overriding closeable infrastructure
resources and asserting shutdown order. Route integration helpers must run
ASGI lifespan explicitly.
- Use
httpx2, not legacy httpx, for generated HTTP client and ASGI transport
tests. Enter LifespanManager, then pass the yielded manager's manager.app
to ASGITransport so request scopes receive lifespan state.
- FastAPI route tests compare response status codes with
fastapi.status
constants, not raw integer literals.
- Use
container.resolve(...) for normal synchronous graph construction, even
when the resolved use case has an async execute(...); use
await container.aresolve(...) only when DI construction itself has async
providers.
- Mock fixtures should register one external collaborator for the behavior
under test. Do not bundle unrelated mocks in a dict or class-keyed fixture.
- Use native pytest fixtures for test dependencies. Do not enable
diwire.integrations.pytest_plugin, and do not use Injected[...]
parameters in tests.
- AnyIO runs tests on every installed supported backend by default. If the app
graph is asyncio-specific, override the top-level
anyio_backend fixture to
return "asyncio"; leave it unpinned only when the suite intentionally
supports every installed backend.
- Do not add filler smoke tests that only assert
container.resolve(...)
returns an instance.
- Do not hand-build application graphs in test bodies. Resolve project classes
from the container; local test doubles may be instantiated in the test module
before registration.
- Keep unit tests free from FastAPI request objects and real external IO.
- Every test directory must include an empty
__init__.py file.
- Use
uv run specx check as the default guardrail mechanism for Specx
boundaries such as docstrings, use-case inputs, UoW injection, route paths,
direct persistence dependency rejection in use cases, container imports,
and AGENTS.md command coverage.
- Disable built-in guardrails only with exact semantic IDs under
[tool.specx].ignore and a project reason recorded beside the configuration.
- Generated projects use
[tool.specx].select = ["ALL"]. Narrower projects
enable technology-specific families explicitly with
[tool.specx].extend-select; FastAPI projects select fastapi.
- Add
extra_rules only for project-specific checks that are not covered by a
built-in SpecxRuleId; use the programmatic wrapper for those projects.
- Existing workflows and projects with custom rules may use
references/render_architecture_guardrails.py to render the tiny wrapper.
Code Style
Use blank lines as logical separators in all code. Keep related statements
together, but separate independent setup, action, assertion, response, branch,
and transformation groups so long blocks stay readable.
References
references/testing.md - folder layout, fixtures, unit/integration examples,
and architecture guardrail snippets.
references/render_architecture_guardrails.py - compatibility renderer for
the tiny specx architecture wrapper.