Subject: Re: [PATCH v2 08/11] fast-export: add --reference-excluded-parents option

From: SZEDER Gábor <[email-masked]>
Date: Wed, 14 Nov 2018 20:27:58 +0100

On Tue, Nov 13, 2018 at 04:25:57PM -0800, Elijah Newren wrote:
> diff --git a/builtin/fast-export.c b/builtin/fast-export.c
> index 2fef00436b..3cc98c31ad 100644
> --- a/builtin/fast-export.c
> +++ b/builtin/fast-export.c
> @@ -37,6 +37,7 @@ static int fake_missing_tagger;
>  static int use_done_feature;
>  static int no_data;
>  static int full_tree;
> +static int reference_excluded_commits;
>  static struct string_list extra_refs = STRING_LIST_INIT_NODUP;
>  static struct string_list tag_refs = STRING_LIST_INIT_NODUP;
>  static struct refspec refspecs = REFSPEC_INIT_FETCH;
> @@ -596,7 +597,8 @@ static void handle_commit(struct commit *commit, struct rev_info *rev,
>  		message += 2;
>  
>  	if (commit->parents &&
> -	    get_object_mark(&commit->parents->item->object) != 0 &&
> +	    (get_object_mark(&commit->parents->item->object) != 0 ||
> +	     reference_excluded_commits) &&
>  	    !full_tree) {
>  		parse_commit_or_die(commit->parents->item);
>  		diff_tree_oid(get_commit_tree_oid(commit->parents->item),
> @@ -644,13 +646,21 @@ static void handle_commit(struct commit *commit, struct rev_info *rev,
>  	unuse_commit_buffer(commit, commit_buffer);
>  
>  	for (i = 0, p = commit->parents; p; p = p->next) {
> -		int mark = get_object_mark(&p->item->object);
> -		if (!mark)
> +		struct object *obj = &p->item->object;
> +		int mark = get_object_mark(obj);
> +
> +		if (!mark && !reference_excluded_commits)
>  			continue;
>  		if (i == 0)
> -			printf("from :%d\n", mark);
> +			printf("from ");
> +		else
> +			printf("merge ");
> +		if (mark)
> +			printf(":%d\n", mark);
>  		else
> -			printf("merge :%d\n", mark);
> +			printf("%s\n", sha1_to_hex(anonymize ?
> +						   anonymize_sha1(&obj->oid) :
> +						   obj->oid.hash));

Since we intend to move away from SHA-1, would this be a good time to
add an anonymize_oid() function, "while at it"?

>  		i++;
>  	}
>  
> @@ -931,13 +941,22 @@ static void handle_tags_and_duplicates(struct string_list *extras)
>  				/*
>  				 * Getting here means we have a commit which
>  				 * was excluded by a negative refspec (e.g.
> -				 * fast-export ^master master).  If the user
> +				 * fast-export ^master master).  If we are
> +				 * referencing excluded commits, set the ref
> +				 * to the exact commit.  Otherwise, the user
>  				 * wants the branch exported but every commit
> -				 * in its history to be deleted, that sounds
> -				 * like a ref deletion to me.
> +				 * in its history to be deleted, which basically
> +				 * just means deletion of the ref.
>  				 */
> -				printf("reset %s\nfrom %s\n\n",
> -				       name, sha1_to_hex(null_sha1));
> +				if (!reference_excluded_commits) {
> +					/* delete the ref */
> +					printf("reset %s\nfrom %s\n\n",
> +					       name, sha1_to_hex(null_sha1));
> +					continue;
> +				}
> +				/* set ref to commit using oid, not mark */
> +				printf("reset %s\nfrom %s\n\n", name,
> +				       sha1_to_hex(commit->object.oid.hash));

Please use oid_to_hex(&commit->object.oid) instead.

>  				continue;
>  			}