del transaction before lock before wlock
This way rollbacks happen while the repo is still locked.
Deleting lock before wlock is not strictly necessary, but is
more consistent with the locking order.
abort: repository a not found!
255
abort: error: Connection refused
255
abort: repository a not found!
255
abort: destination '../a' already exists
255
abort: repository a not found!
255
destination directory: q
abort: destination 'q' already exists