Fixes an issue in Git that leads to being able to delete the currently checked out branch

git-delete-patch.diff

diff --git a/builtin/branch.c b/builtin/branch.c
index 7b45b6b..46bde61 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -215,7 +215,7 @@ static int delete_branches(int argc, const char **argv, int force, int kinds,
 		int flags = 0;
 
 		strbuf_branchname(&bname, argv[i]);
-		if (kinds == FILTER_REFS_BRANCHES && !strcmp(head, bname.buf)) {
+		if (kinds == FILTER_REFS_BRANCHES && !strcasecmp(head, bname.buf)) {
 			error(_("Cannot delete the branch '%s' "
 			      "which you are currently on."), bname.buf);
 			ret = 1;