public function testAddRequiredField()
{
//set up the validator
$requiredFields = new RequiredFields('Title');
//add a field
$requiredFields->addRequiredField('Content');
//check it was added
$this->assertEquals(array('Title', 'Content'), $requiredFields->getRequired(), "Failed to add a new field to the required list");
//add another for good measure
$requiredFields->addRequiredField('Image');
//check it was added
$this->assertEquals(array('Title', 'Content', 'Image'), $requiredFields->getRequired(), "Failed to add a second new field to the required list");
//remove a field
$requiredFields->removeRequiredField('Title');
//check it was removed
$this->assertEquals(array('Content', 'Image'), $requiredFields->getRequired(), "Failed to remove 'Title' field from required list");
//add the same field back to check we can add and remove at will
$requiredFields->addRequiredField('Title');
//check it's in there
$this->assertEquals(array('Content', 'Image', 'Title'), $requiredFields->getRequired(), "Failed to add 'Title' back to the required field list");
//add a field that already exists (we can't have the same field twice, can we?)
$requiredFields->addRequiredField('Content');
//check the field wasn't added
$this->assertEquals(array('Content', 'Image', 'Title'), $requiredFields->getRequired(), "Adding a duplicate field to required field list had unexpected behaviour");
}