Is there some script to find un-delta-able objects?

[Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>]

I.e. something to generate the .gitattributes file using this format:

https://git-scm.com/docs/gitattributes#_packing_objects

Some stuff is obvious, like "*.gpg binary -delta", but I'm wondering if
there's some repo scanner utility to spew this out for a given repo.