* test/ruby/test_eval.rb (class TestEval): Use assert_same instead of
  assert_equal.
* test/ruby/test_hash.rb (class TestHash): ditto.
* test/ruby/test_iseq.rb (class TestISeq): ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43873 b2dd03c8-39d4-4d8f-98ff-823fe69b080e