@Test( expected = PeerException.class )
public void testExecute() throws Exception
{

    doReturn( true ).when( taskResult ).hasSucceeded();
    step.execute();
    verify( trackerOperation ).addLog( anyString() );
    doReturn( true ).when( taskResults ).hasFailures();
    doReturn( false ).when( taskResult ).hasSucceeded();
    step.execute();
}