Re: [PATCH 3/4] builtin/refs: add "update" subcommand

[Junio C Hamano <gitster@pobox.com>]

Patrick Steinhardt <ps@pks.im> writes:

>  git refs delete [--message=<reason>] [--no-deref] <ref> [<oldvalue>]
> +git refs update [--message=<reason>] [--no-deref] [--create-reflog] <ref> <new-value> [<old-value>]

"<old-value> vs <new-value>" is good, we should update "delete" to
use "<old-value>" to match.


>  DESCRIPTION
>  -----------
> @@ -58,6 +59,12 @@ delete::
>  	reference is only deleted after verifying that it currently contains
>  	`<oldvalue>`.
>  
> +update::
> +	Update the given reference to point at `<new-value>`. This subcommand
> +	mirrors `git update-ref` (see linkgit:git-update-ref[1]). When
> +	`<old-value>` is given, the reference is only updated after verifying
> +	that it currently contains `<old-value>`.

As to the lack of "create", among the two potential changes, I have
a slight preference for adding "create" and failing "update" that
does not refer to an existing ref.  If we go that route, the
"--create-reflog" option should move to "create", as "update" will
never be used to create a new ref.


> +	if (repo_get_oid_with_flags(repo, argv[1], &newoid,
> +				    GET_OID_SKIP_AMBIGUITY_CHECK))
> +		die(_("invalid new object ID: %s"), argv[1]);
> +	if (argc == 3 &&
> +	    repo_get_oid_with_flags(repo, argv[2], &oldoid,
> +				    GET_OID_SKIP_AMBIGUITY_CHECK))
> +		die(_("invalid old object ID: %s"), argv[2]);

On the "delete" side, these messages quote the object name, i.e.,

			die(_("invalid old object ID: '%s'"), argv[1]);

We should be consistent.