revert: improve hints on abort when reverting to parent without --all BEFORE: $ hg revert abort: no files or directories specified (use --all to discard all changes) AFTER: Uncommitted changes (using --all *will* nuke edits): $ hg revert abort: no files or directories specified (uncommitted changes, use --all to discard all changes) Clean working directory (using --all won't discard anything): $ hg revert abort: no files or directories specified (use --all to revert all files)