require_relative '../../spec_helper' describe "NilClass#singleton_method" do it "raises regardless of whether NilClass defines the method" do -> { nil.singleton_method(:foo) }.should raise_error(NameError) begin def (nil).foo; end -> { nil.singleton_method(:foo) }.should raise_error(NameError) ensure NilClass.send(:remove_method, :foo) end end end