$this->callAPISuccess('Mailing', 'create', array('name' => 'CiviMail', 'hash' => 'abx'));
$result = $this->callAPISuccess('MailingProviderData', 'get', array('return' => array('mailing_identifier.name', 'contact_identifier', 'mailing_identifier')));
$this->assertEquals(1, $result['count']);
$this->callAPISuccess('Mailing', 'create', array('name' => 'CiviMail', 'hash' => 'abx'));
$result = $this->callAPISuccess('MailingProviderData', 'get', array('return' => array('mailing_identifier.name', 'contact_identifier', 'mailing_identifier')));
$this->assertEquals(1, $result['count']);