/**
* @testdox add() throws a RuntimeException on duplicate elements if the onDuplicate action is "error"
* @expectedException RuntimeException
* @expectedExceptionMessage Item 'foo' already exists
*/
public function testOnDuplicateError()
{
$collection = new NormalizedCollection();
$collection->onDuplicate('error');
$collection->add('foo', 'bar');
$collection->add('foo', 'baz');
}
