MQ: tidy up if a qpush is interrupted.
This aborts the transaction, makes sure the dirtied dirstate isn't
written out, and cleans up the working directory.
#!/bin/sh
hg init
python -c 'print "confuse str.splitlines\nembedded\rnewline"' > a
hg ci -Ama -d '1 0'
echo clean diff >> a
hg ci -mb -d '2 0'
hg diff -r0 -r1