import { WinstonLogger } from '../../../src/logging/WinstonLogger'; describe('WinstonLogger', (): void => { let innerLogger: any; let logger: WinstonLogger; beforeEach(async(): Promise => { innerLogger = { log: jest.fn(), }; logger = new WinstonLogger(innerLogger); }); it('delegates log invocations to the inner logger.', async(): Promise => { expect(logger.log('debug', 'my message', { abc: true })).toBe(logger); expect(innerLogger.log).toHaveBeenCalledTimes(1); expect(innerLogger.log).toHaveBeenCalledWith('debug', 'my message', { abc: true }); }); });