require 'test/unit' class TestAlias < Test::Unit::TestCase class Alias0 def foo "foo" end end class Alias1 < Alias0 alias bar foo def foo "foo+#{super}" end end class Alias2 < Alias1 alias baz foo undef foo end class Alias3 < Alias2 def foo super end def bar super end def quux super end end def test_alias x = Alias2.new assert_equal "foo", x.bar assert_equal "foo+foo", x.baz assert_equal "foo+foo", x.baz # test_check for cache x = Alias3.new assert_raise(NoMethodError) { x.foo } assert_equal "foo", x.bar assert_raise(NoMethodError) { x.quux } end class C def m $SAFE end end def test_JVN_83768862 d = lambda { $SAFE = 4 dclass = Class.new(C) dclass.funcall(:alias_method, :mm, :m) dclass.new }.call assert_raise(SecurityError) { d.mm } end end