toBeFalsy(); expect('')->toBeFalsy(); expect(null)->toBeFalsy(); expect([])->toBeFalsy(); expect(0)->toBeFalsy(); expect('0')->toBeFalsy(); expect(true)->not->toBeFalsy(); expect([1])->not->toBeFalsy(); expect('false')->not->toBeFalsy(); expect(1)->not->toBeFalsy(); expect(-1)->not->toBeFalsy(); }); test('failures', function () { expect(1)->toBeFalsy(); })->throws(ExpectationFailedException::class); test('not failures', function () { expect(null)->not->toBeFalsy(); })->throws(ExpectationFailedException::class);