Skill: Tests and fixtures

Read the bundled conventions before applying this skill.

Decisions that affect behavior

• Inspect the application’s actual runner, suites, bootstrap, environment and scripts. Template source and downloaded application archives may contain different files; a script naming Codeception/PHPUnit does not prove its config or dependencies were shipped. Preserve the existing framework and assertions.
• Select the relevant test boundary. A model test does not exercise routing, authentication filters, serialization, or browser scripts. Use the narrowest existing harness that demonstrates the changed contract without claiming broader coverage from a lower-level check.
• Fixtures have dependencies and load/unload ordering. Keep aliases/data-file paths consistent; do not flatten the dependency graph or rely on test execution order to provide data. Repeated loading must start from the intended isolated state.
• In Yii 22.0, ActiveFixture::load() inserts through schema commands; unload() resets table data. Neither uses the model’s normal save/validation/ behavior lifecycle. Check the runner’s unload/load sequence rather than assuming a direct load() call clears rows. With modelClass and no explicit tableName, initialization selects the model’s getDb() connection, overriding fixture db. Resolve the actual target before either call; a test-named config is not proof of isolation. Yii ActiveRecord has no built-in setDb(); use the application’s existing connection component or verified getDb() override.
• Use explicit disposable databases and synthetic data for destructive fixtures. Transactions are not universal isolation for implicit-commit DDL or multiple connections. Preserve backend-specific tests where SQL behavior depends on it.
• Restore Yii application/container/logger state, class event handlers, time/locale settings and temporary files when a test changes them. Do not force a particular global reset pattern if the existing harness already manages it correctly.

Observable acceptance

Run the affected test(s) through the project’s documented runner and verify the behavior they are intended to detect. For fixture changes demonstrate dependency order and clean reload/unload in the disposable target. Report actual passes, failures/skips and unavailable prerequisites; do not present lint, test discovery, or static skill validation as runtime acceptance or a model evaluation.

Evidence routes

Read framework/test/{Fixture,FixtureTrait,ArrayFixture,DbFixture,ActiveFixture}.php, framework/console/controllers/FixtureController.php, the application test bootstrap, and its runner configuration. Tests: tests/framework/test/FixtureTest.php, tests/framework/test/ActiveFixtureTest.php, tests/framework/console/controllers/FixtureControllerTest.php, and tests/framework/db/ driver-specific ActiveFixture tests. Guides: test-overview, test-unit, test-functional, test-acceptance, test-fixtures.

Install and activate this skill

Select yii2-testing-fixtures in the installation and client verification guide. Install the complete bundle, including referenced resources. The canonical SKILL.md is also available for direct reading.

Continue with the related framework guide.