notes: extract parse_notes_merge_strategy to notes-utils

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/notes.c

@@ -796,17 +796,7 @@ static int merge(int argc, const char **argv, const char *prefix)
 	o.remote_ref = remote_ref.buf;
 
 	if (strategy) {
-		if (!strcmp(strategy, "manual"))
+		if (parse_notes_merge_strategy(strategy, &o.strategy)) {
-			o.strategy = NOTES_MERGE_RESOLVE_MANUAL;
-		else if (!strcmp(strategy, "ours"))
-			o.strategy = NOTES_MERGE_RESOLVE_OURS;
-		else if (!strcmp(strategy, "theirs"))
-			o.strategy = NOTES_MERGE_RESOLVE_THEIRS;
-		else if (!strcmp(strategy, "union"))
-			o.strategy = NOTES_MERGE_RESOLVE_UNION;
-		else if (!strcmp(strategy, "cat_sort_uniq"))
-			o.strategy = NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ;
-		else {
 			error("Unknown -s/--strategy: %s", strategy);
 			usage_with_options(git_notes_merge_usage, options);
 		}

notes-utils.c

@@ -54,6 +54,24 @@ void commit_notes(struct notes_tree *t, const char *msg)
 	strbuf_release(&buf);
 }
 
+int parse_notes_merge_strategy(const char *v, enum notes_merge_strategy *s)
+{
+	if (!strcmp(v, "manual"))
+		*s = NOTES_MERGE_RESOLVE_MANUAL;
+	else if (!strcmp(v, "ours"))
+		*s = NOTES_MERGE_RESOLVE_OURS;
+	else if (!strcmp(v, "theirs"))
+		*s = NOTES_MERGE_RESOLVE_THEIRS;
+	else if (!strcmp(v, "union"))
+		*s = NOTES_MERGE_RESOLVE_UNION;
+	else if (!strcmp(v, "cat_sort_uniq"))
+		*s = NOTES_MERGE_RESOLVE_CAT_SORT_UNIQ;
+	else
+		return -1;
+
+	return 0;
+}
+
 static combine_notes_fn parse_combine_notes_fn(const char *v)
 {
 	if (!strcasecmp(v, "overwrite"))

notes-utils.h

@@ -37,6 +37,7 @@ struct notes_rewrite_cfg {
 	int mode_from_env;
 };
 
+int parse_notes_merge_strategy(const char *v, enum notes_merge_strategy *s);
 struct notes_rewrite_cfg *init_copy_notes_for_rewrite(const char *cmd);
 int copy_note_for_rewrite(struct notes_rewrite_cfg *c,
 			  const unsigned char *from_obj, const unsigned char *to_obj);