/**
* {@inheritDoc}
*/
public function unregisterSubject($id)
{
if (!isset($this->subjects[$id])) {
throw CollectionException::idNotUsed($id);
}
unset($this->subjects[$id]);
}
/**
* Make sure we get the message we are expecting.
*/
public function testIdUsed()
{
$this->assertEquals('The "test" subject unique identifier is already in use.', CollectionException::idUsed('test')->getMessage(), 'Make sure we get the right message.');
}
