... msg) { test. isObject(msg); test. isNumber(msg.id); test. equals(msg.message, txt); test. equals(msg.user, "cjno"); test. done();});}Listing 14.37 shows an attempt at passing the test. ... message";this.room.addMessage("cjno", txt).then(function (msg) { test. isObject(msg); test. isNumber(msg.id); test. equals(msg.message, txt); test. equals(msg.user, "cjno"); test. done();});}Updating the implementation ... function (test) {var room = Object.create(chatRoom);room.addMessage("cjno", null, function (err) { test. isNotNull(err); test. inherits(err, TypeError); test. done();});}The test introduces...