userdiff.c: remove implicit dependency on the_index

[jc: squashed in missing forward decl in userdiff.h found by Ramsay]

Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/userdiff.c b/userdiff.c
index f3f4be5..c913232 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -270,7 +270,8 @@ struct userdiff_driver *userdiff_find_by_name(const char *name) {
 	return userdiff_find_by_namelen(name, len);
 }
 
-struct userdiff_driver *userdiff_find_by_path(const char *path)
+struct userdiff_driver *userdiff_find_by_path(struct index_state *istate,
+					      const char *path)
 {
 	static struct attr_check *check;
 
@@ -278,7 +279,7 @@ struct userdiff_driver *userdiff_find_by_path(const char *path)
 		check = attr_check_initl("diff", NULL);
 	if (!path)
 		return NULL;
-	if (git_check_attr(&the_index, path, check))
+	if (git_check_attr(istate, path, check))
 		return NULL;
 
 	if (ATTR_TRUE(check->items[0].value))