tests/test-journal-exists

diff: add --stat for diffstat output

diff/qdiff --stat invokes patch.diffstat() on the diff output.

When in interactive mode, the output's maximum width is determined by the
terminal's width.

#!/bin/sh

hg init
echo a > a
hg ci -Am0

touch .hg/store/journal

echo foo > a
hg ci -Am0

hg recover