Starting with the newest git version 1.8.2.1, the signature checking code somehow ignores GPG's status-fd and status-file options, which are THE way to machine parse GPG's output (seee [1])
How to reproduce:
1. Put the following line in your ~/.gnupg/gpg.conf file:
status-fd 1
2. Produce a singed commit:
git commit -aS -m "signed test commit"
3. Let git check the signature:
git log -n 1 --show-signature | cat
Output:
Commit 104cffdaaaaed653aasdddddddddd gpg: Signature made Tue 09 Apr 2013 01:09:09 PM CEST using RSA key ID 12345678 gpg: Good signature from "User" Author: user <usermail>
Missing from output is the machine parsable GPG information:
[GNUPG:] SIG_ID sorvifhoerui/asidunb 2013-04-09 23947273 [GNUPG:] GOODSIG 433811111111111324 User <usermail> [GNUPG:] VALIDSIG ddddddddddddddddddfsjidjfv 2013-04-09 aoidfjidh0 0 4 0 1 2 00 oshidvoo444444ddddddddd [GNUPG:] TRUST_ULTIMATE
Note: The git-log format specifiers %GG, %G?, %GK, ... do not provide enough information, as they, for example, do not provide the information, that the signature is valid, if the key is untrusted (which will simply leed to a "bad" signature).
[1] http://www.gnupg.org/documentation/manuals/gnupg-devel/Unattended-Usage.html#Unattended-Usage
