Prevent type exception on concatenation if diffstat returns None.
This will most often occur if diffstat is not installed in the
target platform, though may also happen in other cases where
diffstat fails to execute.
Signed-off-by: Sean Dague <sean@dague.net>
#!/bin/sh
hg
hg -q
hg help
hg -q help
hg add -h
hg add --skjdfks
hg help diff
hg help status
hg -q help status
hg help foo
hg skjdfks
exit 0