Subject: Re: [PATCH 02/10] merge: remove always-the-same "verbose" arguments

From: Junio C Hamano <[email-masked]>
Date: Fri, 14 Oct 2022 11:31:12 -0700

Ævar Arnfjörð Bjarmason  <[email-masked]> writes:

> Simplify the code that builds the arguments for the "read-tree"
> invocation in reset_hard() and read_empty() to remove the "verbose"
> parameter.
>
> Before 172b6428d06 (do not overwrite untracked during merge from
> unborn branch, 2010-11-14) there was a "reset_hard()" function that
> would be called in two places, one of those passed a "verbose=1", the
> other a "verbose=0".
>
> After 172b6428d06 when read_empty() was split off from reset_hard()
> both of these functions only had one caller. The "verbose" in
> read_empty() would always be false, and the one in reset_hard() would
> always be true.
>
> There was never a good reason for the code to act this way, it
> happened because the read_empty() function was a copy/pasted and
> adjusted version of reset_hard().
>
> Since we're no longer conditionally adding the "-v" parameter
> here (and we'd only add it for "reset_hard()" we'll be able to move to
> a simpler and safer run-command API in the subsequent commit.
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <[email-masked]>
> ---
>  builtin/merge.c | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)

I haven't checked the topics in flight that touch the same file, but
as these are file-scope static, it is easy to check the correctness,
and the change of function signature will mean that compilers will
notice after a merge if there is somebody else who still wants them
to be conditionally verbose.

I wonder if these were always unused, or we lost different callers
over time, though.

>
> diff --git a/builtin/merge.c b/builtin/merge.c
> index 5900b81729d..3bb49d805b4 100644
> --- a/builtin/merge.c
> +++ b/builtin/merge.c
> @@ -345,14 +345,12 @@ static int save_state(struct object_id *stash)
>  	return rc;
>  }
>  
> -static void read_empty(const struct object_id *oid, int verbose)
> +static void read_empty(const struct object_id *oid)
>  {
>  	int i = 0;
>  	const char *args[7];
>  
>  	args[i++] = "read-tree";
> -	if (verbose)
> -		args[i++] = "-v";
>  	args[i++] = "-m";
>  	args[i++] = "-u";
>  	args[i++] = empty_tree_oid_hex();
> @@ -363,14 +361,13 @@ static void read_empty(const struct object_id *oid, int verbose)
>  		die(_("read-tree failed"));
>  }
>  
> -static void reset_hard(const struct object_id *oid, int verbose)
> +static void reset_hard(const struct object_id *oid)
>  {
>  	int i = 0;
>  	const char *args[6];
>  
>  	args[i++] = "read-tree";
> -	if (verbose)
> -		args[i++] = "-v";
> +	args[i++] = "-v";
>  	args[i++] = "--reset";
>  	args[i++] = "-u";
>  	args[i++] = oid_to_hex(oid);
> @@ -385,7 +382,7 @@ static void restore_state(const struct object_id *head,
>  {
>  	struct strvec args = STRVEC_INIT;
>  
> -	reset_hard(head, 1);
> +	reset_hard(head);
>  
>  	if (is_null_oid(stash))
>  		goto refresh_cache;
> @@ -1470,7 +1467,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
>  					       check_trust_level);
>  
>  		remote_head_oid = &remoteheads->item->object.oid;
> -		read_empty(remote_head_oid, 0);
> +		read_empty(remote_head_oid);
>  		update_ref("initial pull", "HEAD", remote_head_oid, NULL, 0,
>  			   UPDATE_REFS_DIE_ON_ERR);
>  		goto done;