require 'stringio' describe :prime_next, :shared => true do before(:all) do @orig_stderr = $stderr $stderr = StringIO.new('', 'w') # suppress warning end after(:all) do $stderr = @orig_stderr end it "returns the element at the current position and moves forward" do p = Prime.new p.next.should == 2 p.next.should == 3 p.next.next.should == 6 end end