mock adapter for unit-testing Hubot

I've whacked together a couple of Hubot scripts, but then they started getting more complicated. TDD is really the ONLY way to do any kind of meaningful development. But even if you're not TDD'ing, you are testing, right? Right?

I couldn't find an existing method for writing unit tests for Hubot scripts. After digging around under Hubot's hood, I figured out all I really needed was an Adapter implementation I could spy on. That is what you see here.

example usage

Let's assume you've got a really simple script, like this:

module.exports = function(robot) {
    robot.hear(/Computer!/, function(msg) {
        msg.reply("Why hello there! (ticker tape, ticker tape)");
    });
};

You want to test this, of course. So create a Mocha test:

var expect = require("chai").expect;
var path   = require("path");

var Hubot       = require("hubot");
var Robot       = Hubot.Robot;
var TextMessage = Hubot.TextMessage;

describe("Eddie the shipboard computer", function() {
    var robot;
    var user;
    var adapter;

    beforeEach(function(done) {
        // create new robot, without http, using the mock adapter
        robot = new Robot(null, "mock-adapter", false, "Eddie");

        robot.adapter.on("connected", function() {
            // only load scripts we absolutely need, like auth.coffee
            process.env.HUBOT_AUTH_ADMIN = "1";
            robot.loadFile(
                path.resolve(
                    path.join("node_modules/hubot/src/scripts")
                ),
                "auth.coffee"
            );

            // load the module under test and configure it for the
            // robot.  This is in place of external-scripts
            require("../index")(robot);

            // create a user
            user = robot.brain.userForId("1", {
                name: "mocha",
                room: "#mocha"
            });

            adapter = robot.adapter;

            done();
        });

        robot.run();
    });

    afterEach(function() {
        robot.shutdown();
    });

    it("responds when greeted", function(done) {
        // here's where the magic happens!
        adapter.on("reply", function(envelope, strings) {
            expect(strings[0]).match(/Why hello there/);

            done();
        });

        adapter.receive(new TextMessage(user, "Computer!"));
    });
});

You'll need devDependencies something like this in your package.json:

"devDependencies": {
  "coffee-script": "~1.6.3",
  "chai": "~1.9.0",
  "hubot-mock-adapter": "~1.0.0",
  "mocha": "~1.17.1",
  "hubot": "~2.7.2",
  "sinon": "~1.9.0"
}

That's (almost) all there is to it!

firing up Mocha

Assuming you're using mocha to run your tests, and your tests are in test/, just run node_modules/.bin/mocha --compilers coffee:coffee-script. For less typing, in your package.json, add a test script:

"scripts": {
    "test": "mocha --compilers coffee:coffee-script"
}

Then you can use npm test to run your tests!