$ \textbf{hg update foo}
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ \textbf{hg update}
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ \textbf{hg parents}
changeset:   
branch:      foo
user:        Bryan O'Sullivan <bos@serpentine.com>

summary:     Second commit

$ \textbf{hg update bar}
1 files updated, 0 files merged, 0 files removed, 0 files unresolved