Intermediate Vows.js + Fab.js

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I got my first vows.js test passing last night. Up today, a few more. Hopefully this will take my understanding from the very beginning stages on into intermediate understanding. Hopefully.

I am still working through a fab.js app named player_from_querystring. Accessed with a query string describing a player in my (fab) game, the app responds with a JSON object describing the player.

The test from yesterday describes getting the player object, with ID, back:

var suite = vows.describe('just_playing').
  addBatch({
    'with a query string': {
      topic: function() {
        var player;
        function downstream (obj) { if (obj) player = obj.body; }

        var upstream_listener = player_from_querystring.call(downstream);

        var head = {
          url: { search : "?player=foo&x=1&y=2" },
          headers: { cookie: null }
        };
        upstream_listener(head);

        return player;
      },
      'is player': function (player) {
        assert.equal (player.id, "foo");
      }
    }
  }).export(module);

That is more verbose that seems ideal with vows, but I am not sure how to slim it down just yet. I set up a downstream app / function that sets the out-of-scope player variable with the value returned to it by the upstream app. The upstream app is the player_from_querystring app that I am testing. If I send in a player, via the querystring, with ID of "foo", then I ought to get back a player object with an ID of "foo".

Given that same "topic" of the player returned from a querystring, I would also like to assert that a uniq ID is present. Something along the lines of:

      'has unique ID': function(player) {
        assert.isDefined (player.uniq_id);
      }

Running the vows, I get:

cstrom@whitefall:~/repos/my_fab_game$ vows --spec

♢ just_playing

  with a query string
    ✓ is player
    ✗ has unique ID
    TypeError: Object #<an Object> has no method 'isDefined'
    at Object.<anonymous> (/home/cstrom/repos/my_fab_game/test/just_playing.js:30:16)
    at runTest (/home/cstrom/.node_libraries/.npm/vows/0.4.5/package/lib/vows.js:99:26)
    at EventEmitter.<anonymous> (/home/cstrom/.node_libraries/.npm/vows/0.4.5/package/lib/vows.js:72:9)
    at EventEmitter.emit (events:42:20)
    at /home/cstrom/.node_libraries/.npm/vows/0.4.5/package/lib/vows/suite.js:147:58
    at EventEmitter._tickCallback (node.js:48:25)
    at node.js:204:9
 
✗ Errored » 1 honored ∙ 1 errored (0.104s)

Dang. It was worth a try. The vows.js documentation declares support for assert.isUndefined, so I hoped for a isDefined. Ah well. I end up with this instead, which is not all that pretty:

      'has unique ID': function(player) {
        assert.notEqual (typeof(player.uniq_id), "undefined");
      }

Just to be sure that is legit, I make sure that it fails with player.uniq_. With player.uniq_id, I now have 2 passing tests:

cstrom@whitefall:~/repos/my_fab_game$ vows --spec

♢ just_playing

  with a query string
    ✓ is player
    ✓ has unique ID
 
✓ OK » 2 honored (0.093s)

After adding tests for X-Y coordinates, I try a different "topic" (which I still translate into an RSpec context in my mind). This time, I would like to test that this upstream app terminates the connection with no response if a body (non-querystring) is sent. The context for this looks like:

   addBatch({
     'POSTing data': {
       topic: function() {
         var response;
         function downstream (obj) { response = obj; }

         var upstream_listener = player_from_querystring.call(downstream);
         upstream_listener({body: "foo"});

         return response;
       }
     }
  })

Again, I am saving the response sent to the downstream (fab) app and returning it as the topic of this batch of vows. After sending in an actual body (e.g. a browser POSTed data to this resource), the response ought to be undefined.

To test this, I add this to the "POSTing data" object:

       'is null response': function (topic) {
         assert.isUndefined (topic);
       }

Unfortunately, when I run this test, I get an odd failure:

cstrom@whitefall:~/repos/my_fab_game$ vows --spec

♢ just_playing

  with a query string
    ✓ is player
    ✓ has unique ID
    ✓ has X coordinate
    ✓ has Y coordinate
✗ Errored » just_playing: undefined ∙ Asynchronous Error

✗ Errored » just_playing: POSTing data ∙ not fired!
✗ Errored » 4 honored ∙ 1 errored ∙ 1 dropped

Dang it! I really do want to test for undefined here, but vows.js thinks that returning undefined signals the need for a this.callback call. Sigh. For now, I work around this by returning an array from the topic:

   addBatch({
     'POSTing data': {
       topic: function() {
         var response;
         function downstream (obj) { response = obj; }

         var upstream_listener = player_from_querystring.call(downstream);
         upstream_listener({body: "foo"});

         return [response];
       },

       'is null response': function (topic) {
         assert.isUndefined (topic[0]);
       }
     }
  })

That works:

cstrom@whitefall:~/repos/my_fab_game$ vows --spec

♢ just_playing

  with a query string
    ✓ is player
    ✓ has unique ID
    ✓ has X coordinate
    ✓ has Y coordinate
  POSTing data
    ✓ is null response
 
✓ OK » 5 honored (0.096s)

But it is kinda ugly. I will investigate prettifying it a bit tomorrow.

Day #153