+ mkdir t
+ cd t
+ hg init
+ echo a
+ hg add a
+ hg commit -t test -u test -d '0 0'
+ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
+ hg parents
changeset:   0:acb14030fe0a21b60322c440ad2d20cf7685a376
user:        test
date:        Wed Dec 31 16:00:00 1969
summary:     test

+ hg status
+ hg undo
attempting to rollback last transaction
+ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
0 files, 0 changesets, 0 total revisions
+ hg parents
+ hg status
A a