text: import assert from 'assert';
  
  import toggle from '../toggle';
  
  describe('toggle', () => {
    it('returns first argument', () => {
      assert.equal(toggle('a', 'b', 'b'), 'a');
      assert.equal(toggle('a', 'b')('b'), 'a');
    });
    it('returns second argument', () => {
      assert.equal(toggle('a', 'b', 'a'), 'b');
      assert.equal(toggle('a', 'b')('a'), 'b');
    });
  });
  