test: keep CommandsTest out of app/Commands so parallel runs do not race

[paulbalandan]

Description

The random-order workflow runs components in parallel, and two of them share app/Commands/. That produces this failure in the Commands component:

GeneratorsTest::testSuffixingHasNoEffect
ErrorException: rmdir(/…/app/Commands): Directory not empty

CommandsTest::testDiscoveredCommandsCanBeOverridden (CLI component) copies a fixture into app/Commands/, while the generator tests (Commands component) create files there and remove the directory afterwards. Whenever the CLI fixture is present at that moment, the rmdir() throws. The reverse can also happen: the directory disappears between CommandsTest's mkdir() and copy().

This removes the sharing. CommandsTest no longer writes to app/. The override rule lives in Commands::discoverCommands() (the first class to claim a name wins), so the test require_onces the _command/ListCommands.php fixture and feeds discovery through a mocked locator that lists it ahead of the system ListCommands. This is the same pattern the neighbouring discovery tests use. The copy/delete helpers are gone.

The generator tests are untouched. Their rmdir() cleanup is safe because the Commands component is now the only user of that directory, and a component runs as a single sequential process. The tree is fully restored after both sequential and parallel runs, with no error suppression and no leftover app/Commands/.

Trade-off: the test no longer proves that the real locator lists App before system. It proves the override rule only. The ordering is FileLocator's own contract.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[neznaika0]

After the tests, there’s still other junk left: the sqlite database, test images, empty folders, etc. Should they be deleted to fully revert to the original state?

If so, then the empty folders probably need to be cleaned up.

[michalsn]

Wouldn't the simpler solution be to use @rmdir($dir) here - after all, these are just test cleanups (we can add an inline comment for the reason we use these)?

That way we still clean up the directory when it's empty, but we don't fail if another test happens to be using it at the same time.

[paulbalandan]

The issue here is that both CLI and Commands use the app/Commands/ so an rmdir in one component might corrupt the other one. The alternative I pushed is have Commands own that directly, and rework CLI tests so that it won;t touch app/Commands.

[michalsn]

Okay, thank you - let's see how this works for us.