Ok, I pushed a fix related to this problem 45bb9a2a, this had the amusing effect of
reversing the behavior:

% rm -f $GNUPGHOME/tofu.db ; ( g10/gpg --verify --status-fd=1 /tmp/testmsg
)2>/dev/null | grep TOFU_STATS
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 2 1 0 auto 0 0
[GNUPG:] TOFU_STATS_LONG Verified 1 message signed by "Alpha Test (demo key)
<alpha@example.net>"%0Ain the past 0~seconds.
[GNUPG:] TOFU_STATS 2 1 0 auto 0 0
[GNUPG:] TOFU_STATS_LONG Verified 1 message signed by "Alice (demo key)"%0Ain the
past 0~seconds.

The difference stems from tofu_register setting already_verified to 0 for the first
uid, and to 1 for the second. In the former case, show_statistics is asked to ignore
the current message.

I guess the intention was to handle the very first message differently, but now we
are handling the first *uid* upon receiving the first message differently instead.
I'm not sure how to proceed, hence reassigning to Neal.

This is a GnuPG problem:

teythoon@europa ~/repos/g10/gpgme/obj/tests (git)-[master] % rm $GNUPGHOME/tofu.db && ( gpg2 --verify --with-
colons --status-fd=1 /tmp/testmsg )2>/dev/null | grep TOFU_STATS
[GNUPG:] TOFU_STATS 1 0 0 auto
[GNUPG:] TOFU_STATS_LONG Verified 0 messages signed by "Alfa Test (demo key) <alfa@example.net>".
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 1 0 0 none
teythoon@europa ~/repos/g10/gpgme/obj/tests (git)-[master] % rm $GNUPGHOME/tofu.db && ( gpg2 --verify --with-
colons --status-fd=1 /tmp/testmsg && gpg2 --verify --with-colons --status-fd=1 /tmp/testmsg && sleep 1 && gpg2 -
-verify --with-colons --status-fd=1 /tmp/testmsg )2>/dev/null | grep TOFU_STATS
[GNUPG:] TOFU_STATS 1 0 0 auto
[GNUPG:] TOFU_STATS_LONG Verified 0 messages signed by "Alfa Test (demo key) <alfa@example.net>".
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 1 0 0 none
[GNUPG:] TOFU_STATS 2 1 0 auto 1 1
[GNUPG:] TOFU_STATS_LONG Verified 1 message signed by "Alfa Test (demo key) <alfa@example.net>"%0Ain the past
1~second.
[GNUPG:] TOFU_STATS 2 1 0 auto 1 1
[GNUPG:] TOFU_STATS_LONG Verified 1 message signed by "Alpha Test (demo key) <alpha@example.net>"%0Ain the past
1~second.
[GNUPG:] TOFU_STATS 2 1 0 auto 1 1
[GNUPG:] TOFU_STATS_LONG Verified 1 message signed by "Alice (demo key)"%0Ain the past 1~second.

I don't have time to look at this immediately, but it looks related to Werner's
recent change to the tofu db code.