ThoughtMCP

/** * Tests for Logger utility * * TDD: Write tests first to define expected behavior */ import { afterEach, beforeEach, describe, expect, it, vi } from "vitest"; import { Logger } from "../../../utils/logger"; describe("Logger", () => { let stderrSpy: ReturnType<typeof vi.spyOn>; beforeEach(() => { // Spy on stderr.write to capture log output stderrSpy = vi.spyOn(process.stderr, "write").mockImplementation(() => true) as ReturnType< typeof vi.spyOn >; }); afterEach(() => { stderrSpy.mockRestore(); }); describe("error", () => { it("should write error messages to stderr", () => { Logger.error("Test error message"); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test error message")); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("\n")); }); it("should handle multiple arguments", () => { Logger.error("Error:", "details", 123); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Error: details 123")); }); it("should handle Error objects", () => { const error = new Error("Test error"); Logger.error("Failed:", error); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Failed:")); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test error")); }); }); describe("info", () => { it("should write info messages to stderr", () => { Logger.info("Test info message"); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test info message")); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("\n")); }); it("should handle multiple arguments", () => { Logger.info("Info:", "details", 456); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Info: details 456")); }); }); describe("warn", () => { it("should write warning messages to stderr", () => { Logger.warn("Test warning message"); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test warning message")); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("\n")); }); }); describe("debug", () => { it("should write debug messages to stderr when NODE_ENV is development", () => { const originalEnv = process.env.NODE_ENV; process.env.NODE_ENV = "development"; Logger.debug("Test debug message"); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test debug message")); process.env.NODE_ENV = originalEnv; }); it("should not write debug messages in production", () => { const originalEnv = process.env.NODE_ENV; process.env.NODE_ENV = "production"; Logger.debug("Test debug message"); expect(stderrSpy).not.toHaveBeenCalled(); process.env.NODE_ENV = originalEnv; }); }); describe("log", () => { it("should write log messages to stderr", () => { Logger.log("Test log message"); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("Test log message")); expect(stderrSpy).toHaveBeenCalledWith(expect.stringContaining("\n")); }); }); describe("formatArgs edge cases", () => { it("should format Error object with stack trace", () => { const error = new Error("Test error with stack"); Logger.error(error); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("Test error with stack"); expect(call).toContain("Error:"); }); it("should format Error object without stack trace", () => { const error = new Error("Test error"); delete (error as { stack?: string }).stack; Logger.error(error); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("Test error"); }); it("should handle circular reference in object", () => { const obj: { name: string; self?: unknown } = { name: "test" }; obj.self = obj; // Create circular reference Logger.log(obj); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("[object Object]"); }); it("should handle mixed argument types", () => { const obj = { key: "value" }; const error = new Error("test error"); Logger.log("string", 123, obj, error, true, null, undefined); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("string"); expect(call).toContain("123"); expect(call).toContain("key"); expect(call).toContain("test error"); expect(call).toContain("true"); expect(call).toContain("null"); expect(call).toContain("undefined"); }); it("should handle null argument", () => { Logger.log(null); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("null"); }); it("should handle undefined argument", () => { Logger.log(undefined); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("undefined"); }); it("should handle empty arguments array", () => { Logger.log(); expect(stderrSpy).toHaveBeenCalledWith("\n"); }); it("should format objects with JSON.stringify", () => { const obj = { name: "test", value: 123, nested: { key: "value" } }; Logger.log(obj); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain('"name"'); expect(call).toContain('"test"'); expect(call).toContain('"value"'); expect(call).toContain("123"); expect(call).toContain('"nested"'); }); it("should handle very large objects", () => { const largeObj = { data: new Array(1000).fill("x").join("") }; Logger.log(largeObj); const call = stderrSpy.mock.calls[0][0] as string; expect(call).toContain("data"); expect(call.length).toBeGreaterThan(1000); }); }); });