be-test

Imported from VuKV03/task-manager-web (backend-nest/.claude/skills/be-test/SKILL.md). Install upstream with npx skills add VuKV03/task-manager-web --skill be-test. Copyright stays with the author.

Generate Backend Tests

Scope: Creates unit tests + integration tests for one feature.

Pre-flight Checks

1. Argument provided? Feature name required (e.g., product, auth)
2. Feature exists? Check src/features/{feature-name}/
   • If not → Error: "Feature not found. Run /be-crud {feature} first"
3. Tests already exist? Check src/features/{feature-name}/tests/
   • If exists → Ask: "Tests exist. Add more or overwrite?"

Required Reading (READ FIRST)

Workflow

Step 1: Analyze Feature

Read and understand:

• Service methods (business logic to test)
• Controller endpoints (request/response to test)
• DTOs (validation to test)
• Repository queries (if complex)

Step 2: Summary & Confirmation (REQUIRED — do NOT skip)

Before writing any file, present the full plan and wait for user confirmation.

Output format:

📋 Test plan for feature "{feature-name}"

📁 Files to be CREATED:
- src/features/{feature-name}/tests/{feature}.service.spec.ts
- src/features/{feature-name}/tests/{feature}.controller.spec.ts
- src/features/{feature-name}/tests/{feature}.e2e.spec.ts  (if applicable)

⚠️  {N} test files will be created.

Proceed? (yes / no / adjust)

Rules:

• Do NOT create or edit any file before the user replies "yes" (or equivalent affirmative)
• If user says "no" → stop and ask what to change
• If user says "adjust" / requests changes → update the plan and show it again
• Only after explicit approval → proceed to Step 3

Step 3: Generate Test Files

src/features/{feature-name}/tests/
├── {feature}.service.spec.ts      # Unit tests for service
├── {feature}.controller.spec.ts   # Unit tests for controller
└── {feature}.e2e.spec.ts          # Integration/E2E tests (optional)

Step 4: Write Service Tests

Structure:

describe('{Feature}Service', () => {
  describe('create', () => {
    it('should create entity successfully', async () => {});
    it('should throw error if invalid data', async () => {});
  });
  
  describe('findAll', () => {
    it('should return paginated list', async () => {});
    it('should filter by criteria', async () => {});
  });
  
  describe('findOne', () => {
    it('should return entity by id', async () => {});
    it('should throw NotFoundException if not found', async () => {});
  });
  
  describe('update', () => {
    it('should update entity successfully', async () => {});
    it('should throw error if not found', async () => {});
  });
  
  describe('remove', () => {
    it('should soft delete entity', async () => {});
    it('should throw error if not found', async () => {});
  });
});

Testing patterns:

• Mock repository using jest.mock()
• Test happy path + error cases
• Test edge cases (empty, null, invalid)
• Use beforeEach for setup

Step 5: Write Controller Tests

Structure:

describe('{Feature}Controller', () => {
  describe('POST /{feature}', () => {
    it('should create and return 201', async () => {});
    it('should return 400 for invalid body', async () => {});
    it('should return 401 if unauthorized', async () => {});
  });
  
  describe('GET /{feature}', () => {
    it('should return paginated list', async () => {});
  });
  
  describe('GET /{feature}/:id', () => {
    it('should return entity by id', async () => {});
    it('should return 404 if not found', async () => {});
  });
  
  // ... update, delete
});

Testing patterns:

• Mock service
• Test HTTP status codes
• Test response structure
• Test validation errors

Step 6: Write E2E Tests (Optional)

For critical features, add integration tests:

• Test full request → database flow
• Use test database
• Clean up after tests

Test Coverage Targets

Output

✅ Tests for "{feature-name}" created!

📁 Files created:
- src/features/{feature-name}/tests/
  ├── {feature}.service.spec.ts
  ├── {feature}.controller.spec.ts
  └── {feature}.e2e.spec.ts (if applicable)

🧪 Run tests:
- All tests: `npm run test`
- This feature: `npm run test -- --testPathPattern={feature}`
- Watch mode: `npm run test:watch`
- Coverage: `npm run test:cov`

📊 Expected coverage: 80%+ for service, 70%+ for controller

Important Rules

1. Follow AAA pattern - Arrange, Act, Assert
2. Mock dependencies - Don't hit real database in unit tests
3. Test edge cases - Empty arrays, null values, invalid IDs
4. Descriptive names - "should return 404 when product not found"
5. Independent tests - Each test can run alone

Error Handling