Test cards for Jest

// card.test.ts
import { luhnIsValid, detectScheme } from "./card";

const VISA = "4242424242424242";
const BAD = "4242424242424241";

test("accepts a valid Visa test number", () => {
  expect(luhnIsValid(VISA)).toBe(true);
  expect(detectScheme(VISA)?.network).toBe("visa");
});

test("rejects a number that fails the Luhn check", () => {
  expect(luhnIsValid(BAD)).toBe(false);
});