> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fapost.in/llms.txt
> Use this file to discover all available pages before exploring further.

# Testing and architecture checks

> PHPUnit suites and the PHPat rules that guard boundaries.

Every code change carries a minimal relevant test, and that test is run.

## Commands

```bash theme={"theme":"one-dark-pro"}
composer test
```

Runs the PHPUnit suites declared in `phpunit.xml`. `php artisan test` does the
same; `--compact` is useful when you only care about failures.

```bash theme={"theme":"one-dark-pro"}
composer run test:arch
```

Runs the PHPat architecture rules through PHPStan. The rules live in
`tests/Architecture`. The low-level equivalent:

```bash theme={"theme":"one-dark-pro"}
vendor/bin/phpstan analyse --configuration phpstan.neon
```

<Warning>
  Do not run `php artisan test tests/Architecture` as the architecture check.
  Those classes are not PHPUnit `TestCase`s — the command reports success while
  verifying nothing, which is worse than not running it at all.
</Warning>

The default PHPUnit run does cover PHPat, indirectly: `tests/Unit/Architecture/MigrationTest.php`
invokes PHPStan. So `composer test` catches an architecture violation even when
`test:arch` is not run separately.

## What the architecture rules enforce

They are the executable form of the boundaries described in this section:

* [Dependency direction](/contributing/dependency-direction) — `foundation` and
  `support` must not reference `App\…`
* [Migration isolation](/contributing/migration-isolation) — no runtime state in
  `up()` or `down()`
* [Tenant-aware execution](/contributing/tenant-aware-execution) — no landlord
  access from domains outside `Tenancy`

<Note>
  The PHPat rules and the prose describing them are expected to agree. If you
  change one, change the other — a rule that no document explains gets worked
  around, and a document no rule enforces gets ignored.
</Note>

## Formatting

```bash theme={"theme":"one-dark-pro"}
vendor/bin/pint --dirty --format agent
```

Run after changing PHP.

## What a good test covers

Test the contract, not the implementation. For a node handler that means the
status, the `sourceHandle` per outcome, and the `stateChanges` — those are what
the engine and the flow author depend on.

Tenant isolation deserves explicit coverage wherever code touches persistence. Two
tenants, and an assertion that one cannot see the other's rows, is worth more than
several tests of the happy path — it is the failure that matters most and shows up
least.

Retry safety deserves the same. Execute twice, assert the external effect happened
once. See [Idempotency and retries](/extending/flow-nodes/idempotency).