Eric Blake [off-list ref] writes:
Looking closer at .dotest/0001, the diff is indeed invalid, containing the
single line
That is not a bug in diff but actually in bug in non-merge form of
rebase, which reuses "format patch as if we are sending it out in
e-mail, and apply that on top of a different commit as if we are
accepting that e-mail" machinery. That dataflow loses NUL. Fixing
rebase not to reuse the e-mailed patch dataflow is on my to-do list, but
has been slipping.
So, no, I do not think GIT_EXTERNAL_DIFF would help, as the problem is
not diff generation.
I think you can use "rebase -m" to work this issue around.