How to reproduce https://github.com/hapijs/hapi/issues/2431

test.js

'use strict';

var Hapi = require('hapi'),
  Joi = require('joi');

var server = new Hapi.Server();
server.connection();

server.route({
  method: 'POST',
  path: '/',
  config: {
    validate: {
      payload: Joi.object({
        password: Joi.string(),
        confirm: Joi.object().keys({
          password: Joi.string()
        })
      }).assert('confirm.password', Joi.ref('password'))
    },
    handler: function (request, reply) {
      reply('Ok');
    }
  }
});

server.start(function () {
  server.inject({
    method: 'POST',
    url: '/',
    payload: {
      password: '123456',
      confirm: {
        password: '1234567'
      }
    }
  }, function (response) {
    /*
     Should return { source: 'payload', keys: [ 'confirm.password' ] }
     instead it returns: { source: 'payload', keys: [ 'value' ] }
    */
    console.log(response.result.validation);
  });
  server.stop();
});