dhruvanbhalara/dart-testing

Dart Testing Suite

Contents

• Unit Testing
• Mocking Dependencies
• Test Coverage
• Workflow: Testing Execution

Unit Testing

Utilize package:test as the standard testing library for Dart CLI and backend applications.

• Organize test files to mirror the lib directory structure. Append _test.dart to test files.
• Group related tests using the group() function.
• Use setUp() and tearDown() for shared test state.
• Write pure logic inside Domain/BLoC and extract to static pure functions for 100% unit test coverage.
• Use string interpolation for test group names: group('$ClassName', ...)
• Structure each test using the Arrange-Act-Assert (Given-When-Then) convention:
  • Arrange: Set up mocks, create instances, prepare input data.
  • Act: Call the method under test.
  • Assert: Verify the output or side effects.
• Separate setup from verification to keep tests readable and maintainable.

Mocking Dependencies

Use package:mockito or package:mocktail for dependency mocking.

• Never use real implementation dependencies in unit tests, except for lightweight data models.
• Use @GenerateNiceMocks([MockSpec<YourService>()]) with Mockito, and run build_runner.
• Verify interactions using verify(mockObj.method()).called(1).

Test Coverage

• Target 100% logic coverage for domain models and business logic.
• Run coverage with dart test --coverage=coverage or flutter test --coverage.
• Use format_coverage to convert the lcov.info into an HTML report if needed.

Workflow: Testing Execution

Follow this sequential workflow when testing a Dart feature. Copy the checklist to track progress.

Task Progress

• [ ] Step 1: Write Unit Tests. Focus on core business logic. Ensure files end with _test.dart.
• [ ] Step 2: Generate Mocks. Run dart run build_runner build to generate mocks if using Mockito.
• [ ] Step 3: Run Tests. Execute dart test.
• [ ] Step 4: Check Coverage. Run dart test --coverage=coverage and verify coverage targets are met.