public function testValidateCleanShouldReturnFalseWhenCtypeFunctionReturnsFalse()
{
$ctypeRuleMock = $this->getMockForAbstractClass(AbstractCtypeRule::class);
$ctypeRuleMock->expects($this->once())->method('ctypeFunction')->will($this->returnValue(false));
$this->assertFalse($ctypeRuleMock->validateClean('anything'));
}