test-revert: add case where the file is marked as removed in the wc Unlike untracked, the file is also missing from the working directory. This test highlights a small misbehavior in output when reverting to another revision.

test-revert: add case where wc content is different from "base" and "parent" This test highlights a case where backups are not created and the user may lose data.

test-revert: add case where wc content is already reverted to base content This test highlights multiple misbehaviors of revert. We augment the test comments accordingly.