public function testSlsError()
{
$auth = m::mock('OneLogin_Saml2_Auth');
$saml2 = new Saml2Auth($auth);
$auth->shouldReceive('processSLO')->once();
$auth->shouldReceive('getErrors')->once()->andReturn('errors');
$error = $saml2->sls();
$this->assertNotEmpty($error);
}