PHP Testing

Priority: P1 (HIGH)

Structure

See implementation examples for test directory layout.

Write Tests with PHPUnit and Pest

• Standards: Use

  PHPUnit

  (9/10+) or

  Pest

  . Organize into

  Unit/

  ,

  Integration/

  , and

  Feature/

  . Class names should extend

  TestCase

  .
• TDD Workflow: Follow Red-Green-Refactor. Write failing test first, implement minimal logic, then refactor.

See implementation examples for PHPUnit service test with mock.

Apply Assertions and Data Providers

• Fluent Assertions: Use

  assertSame

  (

  ===

  ) over

  assertEquals

  to avoid type coercion. Also use

  assertCount()

  and

  assertMatchesRegularExpression()

  .
• Data Providers: Use

  #[DataProvider('statusProvider')]

  (PHPUnit 10+) or

  dataset

  (Pest).

See implementation examples for Pest expressive syntax with datasets.

Isolate Test Dependencies

• Mocking: Use

  createMock()

  for dependencies. NOT mock simple Data Objects.
• Isolation: Ensure tests Independent and Repeatable. DB tests must use

  Transactions

  or

  SQLite :memory:

  .
• Coverage: Aim for

  80%+

  line coverage. Use

  phpunit.xml

  to whitelist specific directories.
• Automation: Run tests on every PR using GitHub Actions or GitLab CI.

Anti-Patterns

• No testing private methods: Test through public interfaces only.
• No over-mocking internals: Mock only external boundaries.
• No real network/DB in unit tests: Use in-memory databases or mocks.
• No coverage-metric chasing: Prioritize meaningful assertions.

References

• Testing Patterns & Mocks