Laravel TDD (Pest/PHPUnit)

Write the test first. Watch it fail. Write minimal code to pass. Keep tests fast and realistic.

Test Runner

# Sail
sail artisan test --parallel

# Non-Sail
php artisan test --parallel

Prefer Pest (default in new Laravel apps). PHPUnit is fine if your project uses it.

RED – Write a failing test

• Use model factories; avoid heavy mocking
• Feature tests for HTTP/controllers; unit tests for pure services
• Name tests by behavior

Example (feature):

it('rejects empty email on signup', function () {
    $response = $this->post('/register', [
        'name' => 'Alice',
        'email' => '',
        'password' => 'secret',
        'password_confirmation' => 'secret',
    ]);

    $response->assertSessionHasErrors('email');
});

Run and confirm it fails for the right reason.

GREEN – Minimal implementation

Write the simplest code to pass your failing test. No extras. No refactors.

REFACTOR – Clean up

Remove duplication, clarify names, extract small services. Keep tests green.

Guidelines

• Every production change starts with a failing test
• Watch failures; never skip the failing phase
• Use factories/seeders for realistic data
• Use DB transactions or refreshes in tests as needed
• Keep tests deterministic; avoid sleeps in async flows

When stuck

• If a test is hard to write, design is too coupled; extract a service or port
• Prefer dependency injection; avoid static/global state