Re: [PATCH 08/11] bundle: parse filter capability

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Mar 7, 2022, 15:55 UTC
Message-ID: <220307.86y21lycne.gmgdl@evledraar.gmail.com>
In-Reply-To: <e7dbb46e6acb5c22a0b456135f3af42b974e0268.1645638911.git.gitgitgadget@gmail.com>

On Wed, Feb 23 2022, Derrick Stolee via GitGitGadget wrote:

Show 14 quoted lines

> From: Derrick Stolee <derrickstolee@github.com>
> [...]
>  static int parse_capability(struct bundle_header *header, const char *capability)
> @@ -45,6 +47,11 @@ static int parse_capability(struct bundle_header *header, const char *capability
>  		header->hash_algo = &hash_algos[algo];
>  		return 0;
>  	}
> +	if (skip_prefix(capability, "filter=", &arg)) {
> +		CALLOC_ARRAY(header->filter, 1);
> +		parse_list_objects_filter(header->filter, arg);
> +		return 0;
> +	}
>  	return error(_("unknown capability '%s'"), capability);
>  }

[Something I should have noted in the other reply, but missed].

Before this series we just had the object-format capability, and now we have a 2nd one.

As before we'll return errors un unknown capabilities.

I think it's worthwhile to stop here & think how we think about cross-version compatibility between git versions. I.e. we're not changing the *format version* here (nor is it needed), but just adding a new capability that older gits won't know about.

I don't know if this is a case where older versions could limp along in some cases and still unbundle these, probably that's never happening?

So probably nothing needs to change here, I was just wondering *if* we had capabilities that were optional in some cases whether we shouldn't while-we're-at-it give those some prefix indicating that, and have older versions just issue a warning().

Then have them just try to call index-pack & see if that worked.

But yeah, all of that probably isn't applicable here at all :)