@Test
public void shouldReturnUnhealthyResultIfServerIsPartOfClusterAndLeaderIsUnknown() {

     // we pretend the NOP command failed and the leader field is not set, which means that the cluster is interregna
    NotLeaderException notLeaderException = new NotLeaderException("SELF", null);
    when(distributedStore.nop()).thenReturn(Futures.<Void>immediateFailedFuture(notLeaderException));
    assertThat(check.check().isHealthy(), equalTo(false));
    assertThat(check.check().getError(), nullValue());
}