post_32

index.ts

export function add(...args: number[]): number {
  return args.reduce((a, b) => a + b, 0);
}

// in-source test suites
if (import.meta.vitest) {
  const { it, expect } = import.meta.vitest;
  it("add", () => {
    expect(add()).toBe(0);
    expect(add(1)).toBe(1);
    expect(add(1, 2, 3, 4, 5)).toBe(15);
  });
}