未调用Laika测试中的回调

Question

Meteor.collection.insert() accepts callback as an argument. As an example, one can create a brand new Meteor project and run the following code in the browser's console.

my_collection = new Meteor.Collection("myCollection");
my_collection.insert(
    {some: "object"},
    function() {
        console.log("finished insertion");
    })

When I take this same code and put it in a Laika test, the callback argument never gets called. Here is my test code:

suite('testing Laika out', function() {
    test('inserting into collection', function(done, server, client) {
        client.eval(function() {
            my_collection = new Meteor.Collection("myCollection");
            my_collection.insert(
                {some: "object"},
                function() {
                    console.log("finished insertion");
                    done();
                })
        })
    })
})

Anyone know why the callback function isn't called in this Laika test? This seems to be an issue for more than just Meteor.collection.insert() .

(I'm running Ubuntu 13.04, Meteor 0.7.0.1, Laika 0.3.1, PhantomJS 1.9.2-6)

Answer 1

Well, Mr. jonS90, if you were to run Laika with the --verbose flag, you would notice that an exception is quietly being thrown:

[client log] Exception in delivering result of invoking '/myCollection/insert': ReferenceError: Can't find variable: done

You see, you don't have access to done() in that context. Here's how you should revise your code:

test('inserting into collection', function(done, server, client) {
    client.eval(function() {
        my_collection = new Meteor.Collection("myCollection");

        finishedInsertion = function () {
            console.log("finished insertion");
            emit('done')
        }
        my_collection.insert(
            {some: "object"},
            finishedInsertion)
    })
    client.once('done', function() {
        done();
    })
})

Answer 2

The problem is that you're trying to call done(); inside of your insert callback, when it doesn't exist in that function scope. You actually need to listen for the insertion into my_collection and emit a signal which is picked up by either the client or server (the client in your case). Also, you obviously won't be initializing your collection in your test; that should be done in your production code.

Try this instead:

var assert = require("assert");

suite('testing Laika out', function() {
    test('inserting into collection', function(done, server, client) {

        client.eval(function() {
            addedNew = function(newItem) {
                console.log("finished insertion");
                emit("done", newItem)
            };
            my_collection = new Meteor.Collection("myCollection");
            my_collection.find().observe({
                added: addedNew
            });
            my_collection.insert(
                {some: "object"}
            )
        }).once("done", function(item) {
                assert.equal(item.some, "object");
                done();
            });
    });
})

Check out https://github.com/arunoda/hello-laika for the basic examples for testing.