=== src/utils/helper.test.ts ===
import { helper } from "./helper";

test("helper doubles input", () => {
  expect(helper(5)).toBe(10);
});


=== src/utils/helper.ts ===
export function helper(x: number): number {
  return x * 2;
}


=== src/utils/README.md ===
# Utils

## helper(x)

Doubles the input number.
