pre-push signature hook error reporting [was Re: [PATCH v6] gnu: python-sphinx: Update to 1.4.8.]

[Leo Famulari <leo@famulari.name>]

[-- Attachment #1: Type: text/plain, Size: 1061 bytes --]

On Fri, Jan 13, 2017 at 10:24:00AM -0500, Leo Famulari wrote:
> I bet that you are using the new pre-push hook that verifies commit
> signatures, and you're trying to push some commits that fail the
> signature verification check.
> 
> Someone should add some error reporting to the hook.

In Git 2.11.0, it seems that `git verify-commit` can't tell the user
which commits failed verification:

https://git.kernel.org/cgit/git/git.git/tree/builtin/verify-commit.c?h=v2.11.0

With a warm cache and all the public keys on my machine, checking the
signature of all 17813 commits on the master branch takes ~40 seconds
with `git verify-commit $(git rev-list HEAD)`. This is what the pre-push
hook does now.

Checking the commits one at a time takes ~105 seconds, using something
like this:

for commit in $(git rev-list HEAD); do
	if ! git verify-commit $commit; then
		echo $commit
	fi
done

We could make the hook do something like that. Thoughts? I think the
performance regression is worth the convenience of knowing why it
failed.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]