On Thu, 2018-12-13 at 16:22 -0500, John Passaro wrote:
> Currently, users who do not have GPG installed have no way to discern
> signed from unsigned commits without examining raw commit data. I
> propose two new pretty-print placeholders to expose this information:
> 
> %GR: full ("R"aw) contents of gpgsig header
> %G+: Y/N if the commit has nonempty gpgsig header or not
> 
> The second is of course much more likely to be used, but having exposed
> the one, exposing the other too adds almost no complexity.
> 
> I'm open to suggestion on the names of these placeholders.
> 
> This commit is based on master but e5a329a279 ("run-command: report exec
> failure" 2018-12-11) is required for the tests to pass.
> 
> One note is that this change touches areas of the pretty-format
> documentation that are radically revamped in aw/pretty-trailers: see
> 42617752d4 ("doc: group pretty-format.txt placeholders descriptions"
> 2018-12-08). I have another version of this branch based on that branch
> as well, so you can use that in case conflicts with aw/pretty-trailers
> arise.
> 
> See:
> - https://github.com/jpassaro/git/tree/jp/pretty-expose-gpgsig
> - https://github.com/jpassaro/git/tree/jp/pretty-expose-gpgsig--based-on-aw-pretty-trailers
> 
> John Passaro (4):
>   pretty: expose raw commit signature
>   t/t7510-signed-commit.sh: test new placeholders
>   doc, tests: pretty behavior when gpg missing
>   docs/pretty-formats: add explanation + copy edits
> 
>  Documentation/pretty-formats.txt |  21 ++++--
>  pretty.c                         |  36 ++++++++-
>  t/t7510-signed-commit.sh         | 125 +++++++++++++++++++++++++++++--
>  3 files changed, 167 insertions(+), 15 deletions(-)
> 
> 
> base-commit: 5d826e972970a784bd7a7bdf587512510097b8c7
> prerequisite-patch-id: aedfe228fd293714d9cd0392ac22ff1cba7365db

Just a suggestion: since the raw signature is not very useful without
the commit data to check it against, and the commit data is non-trivial
to construct (requires mangling raw data anyway), maybe you could either
add another placeholder to get the data for signature verification, or
(alternatively or simultaneously) add a placeholder that prints both
data and signature in the OpenPGP message format (i.e. something you can
pass straight to 'gpg --verify').

-- 
Best regards,
Michał Górny