How to show diffs for gpg-encrypted files?

.gitattributes

*.gpg filter=gpg diff=gpg
*.asc filter=gpg diff=gpg

README.md

How to show diffs for gpg-encrypted files?

Git supports showing diffs for encrypted files, but has to be told to do so.

git config --global diff.gpg.textconv "gpg --no-tty --decrypt"

echo "*.gpg filter=gpg diff=gpg" >> .gitattributes
echo "*.asc filter=gpg diff=gpg" >> .gitattributes

or

curl -sL https://gist.github.com/marcelosousaalmeida/e6593b93b388cdf1dbc282dffd424d1b/raw/.gitattributes -o .gitattributes

pass uses textconf = gpg2 -d --quiet --yes --compress-algo=none --no-encrypt-to --batch --use-agent when configured as git repo

If you want to actually see the diff of the GPG messages that normally go to STDERR you have to use a subshell like this:
textconv = sh -c 'gpg --no-tty --decrypt $0 2>&1'