Jakub Narebski [off-list ref] writes:
Diffstat is just a diff format (a way of presenting diff); '--stat'
is described in "Common _diff_ options" of git-log(1) manpage.
But whats obvoud to me might not be obvious to everyone.
To me (and probably many others), a "diff" is the output of the
command "/usr/bin/diff". I notice that git seems to refer to this as
a "patch" instead. Nevertheless, the documentation of --full-diff
explicitly talks about "log -p", rather than "diffs" in general. So
it's not clear from the documentation that it affects other types of
diffs than those produced by -p ("patches").
// Marcus