Prefer rb_check_arity when 0 or 1 arguments

Especially over checking argc then calling rb_scan_args just to
raise an ArgumentError.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66238 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 2 insertions, 3 deletions

diff --git a/transcode.c b/transcode.c
index 9462433130..5f9e4e9600 100644
--- a/transcode.c
+++ b/transcode.c
@@ -4115,10 +4115,9 @@ econv_putback(int argc, VALUE *argv, VALUE self)
     int putbackable;
     VALUE str, max;
 
-    rb_scan_args(argc, argv, "01", &max);
-
-    if (NIL_P(max))
+    if (!rb_check_arity(argc, 0, 1) || NIL_P(max = argv[0])) {
         n = rb_econv_putbackable(ec);
+    }
     else {
         n = NUM2INT(max);
         putbackable = rb_econv_putbackable(ec);