import { describe, expect, it } from 'vitest';
import { assertNever, groupBy, isDefined, sortedEntries } from '../src/index.ts';

describe('@utils', () => {
  it('isDefined 滤掉 null 与 undefined', () => {
    expect([1, null, 2, undefined].filter(isDefined)).toEqual([1, 2]);
  });

  it('groupBy 按键分组', () => {
    const rows = [
      { pn: 'A', type: 'A' as const },
      { pn: 'B', type: 'B' as const },
      { pn: 'C', type: 'A' as const },
    ];
    expect(groupBy(rows, (r) => r.type)).toEqual({
      A: [rows[0], rows[2]],
      B: [rows[1]],
    });
  });

  it('sortedEntries 稳定排序', () => {
    expect(sortedEntries({ b: 2, a: 1 })).toEqual([
      ['a', 1],
      ['b', 2],
    ]);
  });

  it('assertNever 抛错', () => {
    expect(() => assertNever('x' as never)).toThrow('未覆盖的分支');
  });
});