update: do not use the term 'update' when mentioning reverting one file
and give a more precise hint for how to revert such a file
I'm using the term 'revision' instead of 'changeset' in this change to be
consistent with the REV we use in the synopsis.
dispatch: check for None before closing repo
We were trying to call close() if repo == None and req.repo != None.
This can happen when running commands that don't take a repo.
revert: mention update in hint of abort when reverting to non-parent
and explicitly warn about uncommitted changes
Examples:
BEFORE:
$ hg par -q
7:
e81a2efd53d4
$ hg revert -r 2
abort: no files or directories specified
(use --all to discard all changes)
AFTER:
Clean working directory (revert can be easily undone, no edits to be lost):
$ hg revert -r 2
abort: no files or directories specified
(use --all to revert all files, or 'hg update 2' to update)
Uncommitted changes (revert --all *does* discard edits and is pretty hard to
undo or even impossible if --no-backup is specified):
$ hg revert -r 2
abort: no files or directories specified
(uncommitted changes, use --all to discard all changes, or 'hg update 2' to update)