1 files changed, 14 insertions, 0 deletions
diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index 41d3640105..bd4326060c 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -1609,4 +1609,18 @@ End
     t.close
     assert_raise(IOError) {t.binmode}
   end
+
+  def test_threaded_flush
+    bug3585 = '[ruby-core:31348]'
+    src = %q{\
+      t = Thread.new { sleep 3 }
+      Thread.new {sleep 1; t.kill; p 'hi!'}
+      t.join
+    }.gsub(/^\s+/, '')
+    10.times.map do
+      Thread.start do
+        assert_in_out_err([], src, [%q["hi!"]])
+      end
+    end.each {|th| th.join}
+  end
 end