plugin.js

exports = function(server, options, done) {
  server.method('add', function(a, b) {
      return a + b;
    }, {
      callback: false
    });
  done();
};

exports.attributes = {
  name: 'add two numbers server method'
};

test.js

var Hapi = require('hapi'),
  Hoek = require('hoek'),
  Lab = require('lab'),
  lab = exports.lab = Lab.script(),
  experiment = lab.experiment,
  before = lab.before,
  after = lab.after,
  test = lab.test,
  expect = require('code').expect,
  plugin = require('./plugin');


var server = new Hapi.Server();

server.connection();

server.register(plugin, function(err) {
  Hoek.assert(!err, err)
});

before(function(done) {
  server.start(function(err) {
    Hoek.assert(!err, err);
    done();
  });
});

after(function((done)) {
  server.stop(done);
});

experiment('test server method added via plugin', function() {
  test('adds two numbers', function(done) {
    expect(server.methods.add).to.be.a.function();
    expect(server.methods.add(1, 1)).to.equal(2);
    done();
  });
});