Magento 2 Testing

Before writing code

Fetch live docs:

1. Web-search site:developer.adobe.com commerce testing for testing overview
2. Fetch https://developer.adobe.com/commerce/testing/functional-testing-framework/ for MFTF guide
3. Web-search site:developer.adobe.com commerce php development test for unit/integration test patterns

Testing Layers

Unit Tests

Purpose: Test individual classes in isolation.

• Location: Test/Unit/ within the module
• Config: dev/tests/unit/phpunit.xml.dist
• Run: vendor/bin/phpunit -c dev/tests/unit/phpunit.xml.dist app/code/VendorName/ModuleName/Test/Unit/
• Mock all dependencies with PHPUnit mocks or createMock()
• No Magento bootstrap — pure PHP unit testing
• Fast execution, no database or filesystem dependencies

Integration Tests

Purpose: Test module interactions with the Magento framework.

• Location: Test/Integration/ or dev/tests/integration/
• Config: dev/tests/integration/phpunit.xml.dist
• Run: vendor/bin/phpunit -c dev/tests/integration/phpunit.xml.dist
• Uses Magento application bootstrap — real DI, real database
• @magentoDbIsolation enabled — rolls back DB changes after each test
• @magentoAppArea — sets the application area (frontend, adminhtml)
• @magentoConfigFixture — sets config values for the test
• @magentoDataFixture — loads test data
• Slower but tests real interactions

MFTF (Magento Functional Testing Framework)

Purpose: End-to-end browser tests.

• XML-based test definitions (not PHP)
• Converts to Codeception PHP tests
• Uses Selenium WebDriver for browser automation
• Allure reporting for results
• Location: Test/Mftf/Test/, Test/Mftf/ActionGroup/, Test/Mftf/Page/, Test/Mftf/Section/
• Run: vendor/bin/mftf run:test <TestName>
• Tests complete user workflows (add to cart, checkout, admin operations)

API Functional Tests

Purpose: Test REST and SOAP API endpoints.

• Location: dev/tests/api-functional/
• Config: dev/tests/api-functional/phpunit_rest.xml.dist
• Tests API request/response contracts
• Verifies authentication, authorization, and data integrity

Static Tests

Purpose: Code quality and standards.

• Location: dev/tests/static/
• Checks: coding standards (PHP_CodeSniffer + Magento standard), dependency validation, copyright headers
• Run: vendor/bin/phpunit -c dev/tests/static/phpunit.xml.dist

Key Testing Patterns

Mocking in Magento

• Use $this->createMock(ClassName::class) for dependencies
• $mock->expects($this->once())->method('getById')->willReturn($entity)
• For ObjectManager-dependent classes: use ObjectManagerHelper from test framework

Test Data Fixtures

Integration tests use fixtures to set up test state:

• @magentoDataFixture annotation points to a fixture file
• Fixture files create entities (products, customers, orders)
• @magentoDbIsolation rolls back after test

Testing Plugins

Unit test plugin classes independently — call the plugin method with a mock subject and verify behavior.

Testing Observers

Unit test observer's execute() method with a mocked Observer/Event object.

Best Practices

• Write unit tests for all business logic classes
• Use integration tests for DI wiring and database interaction verification
• Use MFTF for critical user journeys (checkout, customer registration)
• Run static tests in CI/CD to enforce coding standards
• Use @magentoDbIsolation to prevent test pollution
• Keep unit tests fast — mock all external dependencies
• Name test methods descriptively: testSaveThrowsExceptionWhenNameIsEmpty()

Fetch the testing documentation for exact annotations, fixture patterns, and MFTF XML schema before writing tests.