@pengwynn There is a test included below for when the header is not included which was based on https://github.com/octokit/octokit.rb/issues/437#issuecomment-36343517. 

Unless you mean nil as in `"X-RateLimit-Remaining" => nil` in which case this breaks since nil will be converted to 0. Can you confirm that header is included and the value if it is?