diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index 5d85927da7..fc55b86176 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -97,6 +97,17 @@ class TestArray < Test::Unit::TestCase
     x = [1,2,3]
     x.concat(x)
     assert_equal([1,2,3,1,2,3], x)
+
+    x = [1,2,3]
+    x.clear
+    assert_equal([], x)
+
+    x = [1,2,3]
+    y = x.dup
+    x << 4
+    y << 5
+    assert_equal([1,2,3,4], x)
+    assert_equal([1,2,3,5], y)
   end
 
   def test_beg_end