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 repo
cd repo
echo foo > foo
hg ci -qAm 'add foo'
echo >> foo
hg ci -m 'change foo'
hg up -qC 0
echo bar > bar
hg ci -qAm 'add bar'
hg log
cd ..
hg init copy
cd copy
echo '% pull a missing revision'
hg pull -qr missing ../repo
echo '% pull -r 0'
hg pull -qr 0 ../repo
hg log
echo '% pull -r 1'
hg pull -qr 1 ../repo
hg log
# this used to abort: received changelog group is empty
echo '% pull -r 1 again'
hg pull -qr 1 ../repo