From: Patrick Steinhardt <ps@pks.im>
Date: Mon, 24 Mar 2025 13:08:16 GMT
Subject: Re: [PATCH v4 8/8] update-ref: add --batch-updates flag for stdin mode
Message-ID: <Z-FZQOYGPIuB2h-t@pks.im>
In-Reply-To: <20250320-245-partially-atomic-ref-updates-v4-8-3dcc1b311dc9@gmail.com>

On Thu, Mar 20, 2025 at 12:44:03PM +0100, Karthik Nayak wrote:
> diff --git a/Documentation/git-update-ref.adoc b/Documentation/git-update-ref.adoc
> index 9e6935d38d..5be2c16776 100644
> --- a/Documentation/git-update-ref.adoc
> +++ b/Documentation/git-update-ref.adoc
> @@ -57,6 +59,14 @@ performs all modifications together.  Specify commands of the form:
>  With `--create-reflog`, update-ref will create a reflog for each ref
>  even if one would not ordinarily be created.
>  
> +With `--batch-updates`, update-ref executes the updates in a batch but allows
> +individual updates to fail due to invalid or incorrect user input, applying only
> +the successful updates. However, system-related errors—such as I/O failures or
> +memory issues—will result in a full failure of all batched updates. Any failed
> +updates will be reported in the following format:
> +
> +	rejected SP (<old-oid> | <old-target>) SP (<new-oid> | <new-target>) SP <rejection-reason> LF
> +

Does this support NUL-terminated mode? It probably should, and if it
does we should also document the format.

> diff --git a/builtin/update-ref.c b/builtin/update-ref.c
> index 1d541e13ad..97e14b279e 100644
> --- a/builtin/update-ref.c
> +++ b/builtin/update-ref.c
> @@ -735,6 +787,8 @@ int cmd_update_ref(int argc,
>  		OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")),
>  		OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")),
>  		OPT_BOOL( 0 , "create-reflog", &create_reflog, N_("create a reflog")),
> +		OPT_BIT('0', "batch-updates", &flags, N_("batch reference updates"),
> +			REF_TRANSACTION_ALLOW_FAILURE),
>  		OPT_END(),
>  	};
>  
> @@ -756,9 +810,10 @@ int cmd_update_ref(int argc,
>  			usage_with_options(git_update_ref_usage, options);
>  		if (end_null)
>  			line_termination = '\0';
> -		update_refs_stdin();
> +		update_refs_stdin(flags);
>  		return 0;
> -	}
> +	} else if (flags & REF_TRANSACTION_ALLOW_FAILURE)
> +		die("--batch-updates can only be used with --stdin");

Nit: formatting, the `else if` branch should have curly braces.

Patrick