testing

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:

process.env.OUTLOOK_RESPONSE_FORMAT = 'text';

Mock Pattern

Mock the Graph client and any module-level dependencies:

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:

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

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');
});