---
description: Jest testing conventions and mock patterns
globs:
- "test/**/*.test.js"
- "__mocks__/**/*.js"
alwaysApply: false
---
# Testing Rules
## Framework
Jest (`npm test`). Tests live in `test/` mirroring source structure:
- `email/list.js` → `test/email/list.test.js`
- `auth/token-manager.js` → `test/auth/token-manager.test.js`
## Response Format in Tests
Tests assert against plain-text output. Set text mode at the top of every test file **before** imports:
```js
process.env.OUTLOOK_RESPONSE_FORMAT = 'text';
```
## Mock Pattern
Mock the Graph client and any module-level dependencies:
```js
const { getGraphClient, graphGetPaginated } = require('../../utils/graph-client');
jest.mock('../../utils/graph-client');
const mockClient = {};
beforeEach(() => {
jest.clearAllMocks();
jest.spyOn(console, 'error').mockImplementation(() => {});
getGraphClient.mockResolvedValue(mockClient);
});
afterEach(() => {
console.error.mockRestore();
});
```
## Assertion Style
- Check `result.content[0].text` for response content
- Check `result.isError` for error responses
- Verify mock call arguments with `expect.objectContaining()`
## Test Structure
Use nested `describe` blocks:
```js
describe('handlerName', () => {
describe('successful operation', () => { ... });
describe('empty results', () => { ... });
describe('error handling', () => {
test('should handle authentication error', ...);
test('should handle Graph API error', ...);
});
});
```
## Auth Error Testing
```js
test('should handle authentication error', async () => {
const authError = new Error('Authentication required');
authError.isAuthError = true;
getGraphClient.mockRejectedValue(authError);
const result = await handler({});
expect(result.isError).toBe(true);
expect(result.content[0].text).toBe('Authentication required');
});
```
