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.
Is there an error message when trying to diff non-existing files?
found: No such file or directory
not: No such file or directory
Is there an error message when trying to add non-existing files?
found: No such file or directory
not: No such file or directory