Map<String, GitTag> tags = new HashMap<String, GitTag>();
tags.put(head_2.getName(), new JGitTag(rawTag));
doReturn(tags).when(repo).getTags();
repo.revWalk = mock(RevWalk.class);
RevFlag seenFlag = RevFlag.UNINTERESTING;
when(repo.revWalk.newFlag("SEEN")).thenReturn(seenFlag);
when(this.repo.getObjectDatabase().newReader().abbreviate(head)).thenReturn(abbrevId);
GitTagDescription description = repo.describe();