Logger.test.ts•6.73 kB
/**
* Unit tests for Logger
*/
import { jest } from '@jest/globals';
import { Logger, LogLevel, createLogger } from '../../utils/Logger';
describe('Logger', () => {
const originalLog = console.log;
const originalWarn = console.warn;
const originalError = console.error;
const originalDebug = console.debug;
let consoleLogMock: ReturnType<typeof jest.fn>;
let consoleWarnMock: ReturnType<typeof jest.fn>;
let consoleErrorMock: ReturnType<typeof jest.fn>;
let consoleDebugMock: ReturnType<typeof jest.fn>;
beforeEach(() => {
consoleLogMock = jest.fn();
consoleWarnMock = jest.fn();
consoleErrorMock = jest.fn();
consoleDebugMock = jest.fn();
console.log = consoleLogMock;
console.warn = consoleWarnMock;
console.error = consoleErrorMock;
console.debug = consoleDebugMock;
});
afterEach(() => {
console.log = originalLog;
console.warn = originalWarn;
console.error = originalError;
console.debug = originalDebug;
});
describe('Log Levels', () => {
it('should log debug messages when level is DEBUG', () => {
const logger = new Logger({ level: LogLevel.DEBUG });
logger.debug('test debug');
expect(consoleDebugMock).toHaveBeenCalledWith(
expect.stringContaining('[DEBUG] test debug')
);
});
it('should not log debug messages when level is INFO', () => {
const logger = new Logger({ level: LogLevel.INFO });
logger.debug('test debug');
expect(consoleDebugMock).not.toHaveBeenCalled();
});
it('should log info messages when level is INFO', () => {
const logger = new Logger({ level: LogLevel.INFO });
logger.info('test info');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringContaining('[INFO] test info')
);
});
it('should log warnings when level is WARN', () => {
const logger = new Logger({ level: LogLevel.WARN });
logger.warn('test warning');
expect(consoleWarnMock).toHaveBeenCalledWith(
expect.stringContaining('[WARN] test warning')
);
});
it('should not log info when level is WARN', () => {
const logger = new Logger({ level: LogLevel.WARN });
logger.info('test info');
expect(consoleLogMock).not.toHaveBeenCalled();
});
it('should log errors when level is ERROR', () => {
const logger = new Logger({ level: LogLevel.ERROR });
logger.error('test error');
expect(consoleErrorMock).toHaveBeenCalledWith(
expect.stringContaining('[ERROR] test error')
);
});
it('should not log anything when level is SILENT', () => {
const logger = new Logger({ level: LogLevel.SILENT });
logger.debug('debug');
logger.info('info');
logger.warn('warn');
logger.error('error');
expect(consoleDebugMock).not.toHaveBeenCalled();
expect(consoleLogMock).not.toHaveBeenCalled();
expect(consoleWarnMock).not.toHaveBeenCalled();
expect(consoleErrorMock).not.toHaveBeenCalled();
});
});
describe('Formatting', () => {
it('should include prefix when configured', () => {
const logger = new Logger({ prefix: 'TestModule', level: LogLevel.INFO });
logger.info('test message');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringContaining('[TestModule]')
);
});
it('should include timestamp when configured', () => {
const logger = new Logger({ timestamp: true, level: LogLevel.INFO });
logger.info('test message');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringMatching(/^\d{4}-\d{2}-\d{2}T/)
);
});
it('should format with all components', () => {
const logger = new Logger({
prefix: 'Test',
timestamp: true,
level: LogLevel.INFO,
});
logger.info('message');
const call = consoleLogMock.mock.calls[0][0] as string;
expect(call).toMatch(/^\d{4}/); // Timestamp
expect(call).toContain('[Test]'); // Prefix
expect(call).toContain('[INFO]'); // Level
expect(call).toContain('message'); // Message
});
});
describe('Child Loggers', () => {
it('should create child logger with combined prefix', () => {
const parent = new Logger({ prefix: 'Parent', level: LogLevel.INFO });
const child = parent.child('Child');
child.info('test');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringContaining('[Parent:Child]')
);
});
it('should inherit log level from parent', () => {
const parent = new Logger({ level: LogLevel.ERROR });
const child = parent.child('Child');
child.info('should not log');
child.error('should log');
expect(consoleLogMock).not.toHaveBeenCalled();
expect(consoleErrorMock).toHaveBeenCalled();
});
});
describe('Dynamic Level Changes', () => {
it('should allow changing log level', () => {
const logger = new Logger({ level: LogLevel.ERROR });
logger.info('not logged');
expect(consoleLogMock).not.toHaveBeenCalled();
logger.setLevel(LogLevel.INFO);
logger.info('now logged');
expect(consoleLogMock).toHaveBeenCalled();
});
it('should return current log level', () => {
const logger = new Logger({ level: LogLevel.WARN });
expect(logger.getLevel()).toBe(LogLevel.WARN);
logger.setLevel(LogLevel.DEBUG);
expect(logger.getLevel()).toBe(LogLevel.DEBUG);
});
});
describe('Success Messages', () => {
it('should log success messages at INFO level', () => {
const logger = new Logger({ level: LogLevel.INFO });
logger.success('operation complete');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringContaining('[✓] operation complete')
);
});
it('should not log success when level is WARN', () => {
const logger = new Logger({ level: LogLevel.WARN });
logger.success('operation complete');
expect(consoleLogMock).not.toHaveBeenCalled();
});
});
describe('Additional Arguments', () => {
it('should pass additional arguments to console', () => {
const logger = new Logger({ level: LogLevel.INFO });
const obj = { foo: 'bar' };
logger.info('message', obj, 123);
expect(consoleLogMock).toHaveBeenCalledWith(
expect.any(String),
obj,
123
);
});
});
describe('Factory Function', () => {
it('should create logger with module prefix', () => {
const logger = createLogger('MyModule');
logger.info('test');
expect(consoleLogMock).toHaveBeenCalledWith(
expect.stringContaining('[MyModule]')
);
});
});
});