Re: git pull --prune --prune-tags yields a usage error In 2.45.0

From: Patrick Steinhardt <ps@pks.im>
Date: May 14, 2024, 06:47 UTC
Message-ID: <ZkMJHMtiQWw4qdT2@tanuki>
In-Reply-To: <CAC-6ESEfnjK1ubrzoAfUsegM55e55uKugCPSfxnBC607dmZJRA@mail.gmail.com>

On Mon, May 13, 2024 at 07:11:00PM -0400, David Sanderson wrote:

Show 11 quoted lines

> I noticed that "git help pull"  mentioned the flag --prune-tags in
> conjunction with --prune, but actually supplying this flag to
> "git pull" results in a usage error.  For instance, the command
> "git pull --prune --prune-tags" fails with a usage error.  I would
> have expected that this would work, since it works with "git fetch".
> 
> I could use "git fetch --prune --prune-tags" as I expected, and
> "git help fetch" does describe --prune-tags on its own as well as
> in the help for --prune.
> 
> I confirmed that this behavior still exists in git version 2.45.0.

Indeed. The fact that we mention `--prune-tags` in git-pull(1) at all is a bug because that command never even implemented this option. I could see us going one of two ways:

  - Adapt the documentation so that we stop mentioning `--prune-tags`.

  - Implement support for `--prune-tags` in git-pull(1).

I find the value of `--prune-tags` to be rather dubious as it does the exact same as `git fetch --prune refs/tags/*:refs/tags/*`. I am heavily biased though as I understand refspecs just fine, which many of our users may not. But the bigger downside of `--prune-tags` in my opinion is that it doesn't only prune tags, but also fetches new ones. So the effect of the option is somewhat counterintuitive.

So with that in mind I'd rather pick option 1 and stop mentioning the option in git-pull(1). But that's only a preference of myself, not a strong "no", and am very happy to be convinced otherwise.

So unless somebody does feel strongly that `--prune-tags` should exist and provides the patches, my proposal would be to remove the mention of `--prune-tags` from git-pull(1) for now. We can then add it back in if somebody does implement the option in the future.

Patrick