visionmedia/node-response-send — pull request #2 by georgecalm (2012-07-16 20:18:18+00:00)
Title: Ensuring that the status-code isn't badly overridden

When calling express' `res.json(code, data)` with an undefined `code` argument, the app throws a `TypeError: Cannot call method 'toString' of undefined
at ServerResponse.writeHead (http.js:980:45)`.

So, `res.json()` sets a bad (undefined) statusCode and `response-send#send()` doesn't check it before calling `ServerResponse#send()`. Since it's also possible to call `response-send#send()` with a bad statusCode, I thought the method would benefit from a statusCode check.