Re: [PATCH v1 1/1] rev-list: add --missing=print-only mode

> When working with partial clones, it's common to want just the list of
> missing objects. The current --missing=print mode does this but mixes
> present and missing objects together, with missing ones prefixed by '?'.
> Getting only the missing OIDs requires an extra pipe:
> 
>    git rev-list --objects --all --missing=print | perl -ne 'print if s/^[?]//'
> 
> Add --missing=print-only which outputs only the missing object OIDs, one
> per line, without any prefix. This makes the above one-liner unnecessary
> and the output directly usable by downstream tools.

>   static struct oidmap missing_objects;
>   enum missing_action {
> -	MA_ERROR = 0,    /* fail if any missing objects are encountered */
> -	MA_ALLOW_ANY,    /* silently allow ALL missing objects */
> -	MA_PRINT,        /* print ALL missing objects in special section */
> -	MA_PRINT_INFO,   /* same as MA_PRINT but also prints missing object info */
> +	MA_ERROR = 0, /* fail if any missing objects are encountered */
> +	MA_ALLOW_ANY, /* silently allow ALL missing objects */
> +	MA_PRINT, /* print ALL missing objects in special section */
> +	MA_PRINT_INFO, /* same as MA_PRINT but also prints missing object info */
> +	MA_PRINT_ONLY, /* print ONLY missing objects, without the "?" prefix */
>   	MA_ALLOW_PROMISOR, /* silently allow all missing PROMISOR objects */

> +		return;
> +	} else if (line_term) {
>   		printf("?%s", oid_to_hex(&entry->entry.oid));
> -	else
> +	} else {
>   		printf("%s%cmissing=yes", oid_to_hex(&entry->entry.oid),
>   		       info_term);
> +	}

>   	if (!print_missing_info) {
>   		putchar(line_term);
> @@ -209,6 +222,7 @@ static inline void finish_object__ma(struct object *obj, const char *name)
>   
>   	case MA_PRINT:
>   	case MA_PRINT_INFO:
> +	case MA_PRINT_ONLY:
>   		add_missing_object_entry(&obj->oid, name, obj->type);
>   		return;
>   
> @@ -246,6 +260,11 @@ static void show_commit(struct commit *commit, void *data)
>   		return;
>   	}
>   
> +	if (arg_missing_action == MA_PRINT_ONLY) {
> +		finish_commit(commit);
> +		return;
> +	}
> +
>   	if (show_disk_usage)
>   		total_disk_usage += get_object_disk_usage(&commit->object);
>   
> @@ -384,6 +403,8 @@ static void show_object(struct object *obj, const char *name, void *cb_data)
>   	if (finish_object(obj, name, cb_data))
>   		return;
>   	display_progress(progress, ++progress_counter);
> +	if (arg_missing_action == MA_PRINT_ONLY)
> +		return;
>   	if (show_disk_usage)
>   		total_disk_usage += get_object_disk_usage(obj);
>   	if (info->flags & REV_LIST_QUIET)
> @@ -525,6 +546,12 @@ static inline int parse_missing_action_value(const char *value)
>   		return 1;
>   	}
>   
> +	if (!strcmp(value, "print-only")) {
> +		arg_missing_action = MA_PRINT_ONLY;
> +		fetch_if_missing = 0;
> +		return 1;
> +	}
> +
>   	if (!strcmp(value, "allow-promisor")) {
>   		arg_missing_action = MA_ALLOW_PROMISOR;
>   		fetch_if_missing = 0;
> @@ -967,8 +994,7 @@ int cmd_rev_list(int argc,
>   
>   	if (arg_print_omitted)
>   		oidset_init(&omitted_objects, DEFAULT_OIDSET_SIZE);
> -	if (arg_missing_action == MA_PRINT ||
> -	    arg_missing_action == MA_PRINT_INFO) {
> +	if (missing_action_prints()) {
>   		struct oidset_iter iter;
>   		struct object_id *oid;
>   
> @@ -994,8 +1020,7 @@ int cmd_rev_list(int argc,
>   			printf("~%s\n", oid_to_hex(oid));
>   		oidset_clear(&omitted_objects);
>   	}
> -	if (arg_missing_action == MA_PRINT ||
> -	    arg_missing_action == MA_PRINT_INFO) {
> +	if (missing_action_prints()) {
>   		struct missing_objects_map_entry *entry;
>   		struct oidmap_iter iter;
>   
> @@ -1011,7 +1036,7 @@ int cmd_rev_list(int argc,
>   
>   	stop_progress(&progress);
>   
> -	if (revs.count) {
> +	if (revs.count && arg_missing_action != MA_PRINT_ONLY) {
>   		if (revs.left_right && revs.cherry_mark)
>   			printf("%d\t%d\t%d\n", revs.count_left, revs.count_right, revs.count_same);
>   		else if (revs.left_right)
> @@ -1022,7 +1047,7 @@ int cmd_rev_list(int argc,
>   			printf("%d\n", revs.count_left + revs.count_right);
>   	}
>   
> -	if (show_disk_usage)
> +	if (show_disk_usage && arg_missing_action != MA_PRINT_ONLY)
>   		print_disk_usage(total_disk_usage);