/**
* Tests for logger utility
*/
import { Logger, logger, setDebugMode } from "../../src/utils/logger";
describe("Logger", () => {
let mockConsole: {
log: jest.SpyInstance;
error: jest.SpyInstance;
warn: jest.SpyInstance;
};
beforeEach(() => {
mockConsole = {
log: jest.spyOn(console, "log").mockImplementation(),
error: jest.spyOn(console, "error").mockImplementation(),
warn: jest.spyOn(console, "warn").mockImplementation(),
};
});
afterEach(() => {
jest.restoreAllMocks();
});
describe("Logger class", () => {
it("should create logger with debug disabled by default", () => {
const testLogger = new Logger();
testLogger.debug("test message");
expect(mockConsole.log).not.toHaveBeenCalled();
});
it("should create logger with debug enabled when specified", () => {
const testLogger = new Logger(true);
testLogger.debug("test message");
expect(mockConsole.log).toHaveBeenCalledWith("[DEBUG] test message");
});
it("should log info messages", () => {
const testLogger = new Logger();
testLogger.info("test info message", "extra", 123);
expect(mockConsole.log).toHaveBeenCalledWith(
"[INFO] test info message",
"extra",
123,
);
});
it("should log error messages", () => {
const testLogger = new Logger();
testLogger.error("test error message", { code: 500 });
expect(mockConsole.error).toHaveBeenCalledWith(
"[ERROR] test error message",
{ code: 500 },
);
});
it("should log warning messages", () => {
const testLogger = new Logger();
testLogger.warn("test warning message");
expect(mockConsole.warn).toHaveBeenCalledWith(
"[WARN] test warning message",
);
});
it("should enable debug mode dynamically", () => {
const testLogger = new Logger(false);
// Debug disabled initially
testLogger.debug("first message");
expect(mockConsole.log).not.toHaveBeenCalled();
// Enable debug
testLogger.setDebugMode(true);
testLogger.debug("second message");
expect(mockConsole.log).toHaveBeenCalledWith("[DEBUG] second message");
// Disable debug again
testLogger.setDebugMode(false);
mockConsole.log.mockClear();
testLogger.debug("third message");
expect(mockConsole.log).not.toHaveBeenCalled();
});
});
describe("Global logger", () => {
it("should have a global logger instance", () => {
expect(logger).toBeInstanceOf(Logger);
});
it("should allow setting debug mode globally", () => {
setDebugMode(true);
logger.debug("global debug test");
expect(mockConsole.log).toHaveBeenCalledWith("[DEBUG] global debug test");
setDebugMode(false);
mockConsole.log.mockClear();
logger.debug("disabled debug test");
expect(mockConsole.log).not.toHaveBeenCalled();
});
it("should handle multiple arguments in log methods", () => {
const complexObject = { nested: { value: "test" }, array: [1, 2, 3] };
logger.info("Complex log", complexObject, "string", 42, true);
expect(mockConsole.log).toHaveBeenCalledWith(
"[INFO] Complex log",
complexObject,
"string",
42,
true,
);
});
});
describe("Edge cases", () => {
it("should handle empty messages", () => {
const testLogger = new Logger();
testLogger.info("");
testLogger.error("");
testLogger.warn("");
expect(mockConsole.log).toHaveBeenCalledWith("[INFO] ");
expect(mockConsole.error).toHaveBeenCalledWith("[ERROR] ");
expect(mockConsole.warn).toHaveBeenCalledWith("[WARN] ");
});
it("should handle special characters in messages", () => {
const testLogger = new Logger();
const specialMessage =
'Message with 🎉 emojis and \nnewlines and "quotes" and \\backslashes';
testLogger.info(specialMessage);
expect(mockConsole.log).toHaveBeenCalledWith(`[INFO] ${specialMessage}`);
});
it("should handle null and undefined arguments", () => {
const testLogger = new Logger();
testLogger.info("test", null, undefined, 0, false, "");
expect(mockConsole.log).toHaveBeenCalledWith(
"[INFO] test",
null,
undefined,
0,
false,
"",
);
});
});
describe("Performance", () => {
it("should not execute debug message construction when debug is disabled", () => {
const testLogger = new Logger(false);
const expensiveOperation = jest.fn(() => "expensive result");
// This should not call the expensive operation
testLogger.debug("Debug message", expensiveOperation());
expect(expensiveOperation).toHaveBeenCalled(); // Note: args are still evaluated
expect(mockConsole.log).not.toHaveBeenCalled();
});
});
});
