hackety.js

var givens = {};
var Given = function (pattern, topicGenerator) {
  givens[pattern] = topicGenerator;
};

var whens = {};
var When = function (pattern, topicGenerator) {
  whens[pattern] = topicGenerator;
};

var thens = {};
var Then = function (pattern, callbackGenerator) {
  thens[pattern] = callbackGenerator;
});

Given(/^I have a httpServer$/, function () {
  return function (topic) {
    // Always use or extend the same topic since you don't know how nested or not nested you are at this point
    topic = topic || {};
    topic.server = require("http").createServer().listen(8080);
    return topic;
  };

});

Given(/^my httpServer responds with "(.+)"$/, function (responseBody) {
  return function (topic) {
    topic = topic || {};
    topic.server.on("request", function (req, res) {
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.end(responseBody + '\n');
    });
    return topic;
  };
});

When(/^I make a request$/, function () {
  return function (topic) {
    topic = topic || {};
    var client = require("http").createClient(8080, "localhost");
    var req = client.request("GET", "/");
    req.end();
    req.on("response", function (res) {
      res.on("data", function (data) {
        this.callback(data);
      });
    });
  };
});

Then(/^I should see "(.+)"$/, function (str) {
  return function (data) { // The callback
    assert.equal(data, str);
  };
});

fs.readFile("./httpServer.feature", function (err, data) {
  data.split("\n");
  // Parse out Givens, Whens, Thens
  // Match via givens, whens, and thens maps defined in step defs
  // Use mapped values in a vows structure.
});

httpServer.feature

Given I have a httpServer
And my httpServer responds with "Hello World"
When I make a request
Then I should see "Hello World"