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.

#!/bin/sh

hg init dir
cd dir
echo bleh > bar
hg add bar
hg ci -m 'add bar'

hg cp bar foo
echo >> bar
hg ci -m 'cp bar foo; change bar'

hg debugrename foo
hg debugindex .hg/store/data/bar.i