Minimal unit testing framework (TypeScript)

tester.ts

function assert(arg1: any, arg2: any) {
  if (arg1 != arg2) throw new Error(`Expected ${arg1} to equal ${arg2}`);
}

const PASS = ['32']; // green
const FAIL = ['31', '1']; // red, bold

function logStyle(codes: string | string[], text: string) {
  if (Array.isArray(codes)) codes = codes.join(';');
  console.log(`\x1b[${codes}m${text}\x1b[0m`);
}

class Tester {
  constructor() {}

  test(name: string, fn: () => void) {
    try {
      fn();
      logStyle(PASS, `${name} PASSED`);
    } catch (e) {
      logStyle(
        FAIL,
        `${name} FAILED:
  ${e}`
      );
    }
  }
}

/**
 * Usage:
 *   const t = new Tester();
 *   t.test('testName', () => {
 *     assert(1, 1);
 *     assert(1, 2); // will fail
 *   });
 */