create-test

Testing Skill

This skill defines the process for writing and running unit and widget tests in the project.

1. Directory Structure

Test files must mirror the lib/src/ directory hierarchy under test/:

lib/src/
└── infrastructure/
    └── auth/
        └── auth_repository.dart

test/src/
└── infrastructure/
    └── auth/
        └── auth_repository_test.dart

All test files must end with the _test.dart suffix.

2. Mocking Guidelines

• Mocking Tool: Use the mockito package for mocking infrastructure and external client dependencies.
• Generator: Annotate test files with @GenerateMocks to auto-generate mocks using build_runner.

2.1 Generating Mocks Example

Annotate your test file's main() method with the dependencies to mock:

import 'package:apple_project/src/infrastructure/auth/auth_repository.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:mockito/annotations.dart';
import 'package:mockito/mockito.dart';

// Import the generated mock file (ends with .mocks.dart)
import 'auth_repository_test.mocks.dart';

@GenerateMocks([AuthRepository])
void main() {
  // Test code goes here
}

To build/generate the mock implementation, run:

melos run generate

3. Writing Unit Tests

Structure tests logically using group, test, and standard Mockito APIs:

void main() {
  late MockAuthRepository mockAuthRepo;

  setUp(() {
    mockAuthRepo = MockAuthRepository();
  });

  group('AuthRepository Tests', () {
    test('login returns success on correct credentials', () async {
      // Arrange
      when(mockAuthRepo.login('user', 'pass'))
          .thenAnswer((_) async => const Ok(null));

      // Act
      final result = await mockAuthRepo.login('user', 'pass');

      // Assert
      expect(result.isOk, isTrue);
      verify(mockAuthRepo.login('user', 'pass')).called(1);
    });
  });
}

4. Running Tests

• Run all unit and widget tests:

  flutter test
  

• Run tests for a specific test file:

  flutter test test/src/infrastructure/auth/auth_repository_test.dart