add a test for Kernel.open(Pathname.new(...)) { ... }.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@6273 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/pathname.rb

@@ -1182,5 +1182,9 @@ if $0 == __FILE__
       assert_not_same(str, obj.to_s)
       assert_not_same(obj.to_s, obj.to_s)
     end
+
+    def test_kernel_open
+      assert_equal(1, Kernel.open(Pathname.new("/dev/null")) {|f| 1 })
+    end
   end
 end