import { describe, expect, it } from 'vitest';

import { cx } from './cx';

describe('cx', () => {
  it('joins strings with a single space', () => {
    expect(cx('px-2', 'py-1')).toBe('px-2 py-1');
  });

  it('drops every falsy value', () => {
    expect(cx('a', false, null, undefined, '', 0, 'b')).toBe('a b');
  });

  it('keeps truthy numbers, since a class can legitimately be numeric', () => {
    expect(cx(1, 'a')).toBe('1 a');
  });

  it('flattens arrays, including nested ones', () => {
    expect(cx(['a', ['b', ['c']]], 'd')).toBe('a b c d');
  });

  it('takes object keys whose value is truthy', () => {
    expect(cx({ a: true, b: false, c: 1, d: 0, e: 'yes' })).toBe('a c e');
  });

  it('supports the conditional idiom components rely on', () => {
    const disabled = false;
    const active = true;
    expect(cx('base', active && 'is-active', disabled && 'is-disabled')).toBe('base is-active');
  });

  it('mixes every input form in one call', () => {
    expect(cx('a', ['b', { c: true, d: false }], undefined, { e: 1 })).toBe('a b c e');
  });

  it('returns an empty string when nothing survives', () => {
    expect(cx(null, undefined, false, {}, [])).toBe('');
  });
});