fails:Module#undef_method is a private method
fails:Module#undef_method requires multiple arguments
fails:Module#undef_method does not undef any instance methods when argument not given
fails:Module#undef_method returns self
fails:Module#undef_method raises a NameError when passed a missing name
fails:Module#undef_method on frozen instance raises a RuntimeError when passed a name
fails:Module#undef_method on frozen instance raises a RuntimeError when passed a missing name
fails:Module#undef_method on frozen instance raises a TypeError when passed a not name
fails:Module#undef_method on frozen instance does not raise exceptions when no arguments given
