Warn non-nil `$,` in `IO#print` too

2 files changed, 4 insertions, 1 deletions

diff --git a/io.c b/io.c
index 19fe51bcf6..b3175df6c0 100644
--- a/io.c
+++ b/io.c
@@ -7615,6 +7615,9 @@ rb_io_print(int argc, const VALUE *argv, VALUE out)
 	line = rb_lastline_get();
 	argv = &line;
     }
+    if (argc > 1 && !NIL_P(rb_output_fs)) {
+        rb_warn("$, is set to non-nil value");
+    }
     for (i=0; i<argc; i++) {
 	if (!NIL_P(rb_output_fs) && i>0) {
 	    rb_io_write(out, rb_output_fs);
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index 6bdc7bb27f..af2b08de95 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -2572,7 +2572,7 @@ class TestIO < Test::Unit::TestCase
     $\ = "\n"
     pipe(proc do |w|
       w.print('a')
-      w.print('a','b','c')
+      EnvUtil.suppress_warning {w.print('a','b','c')}
       w.close
     end, proc do |r|
       assert_equal("a\n", r.gets)