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More Object based creation of 'step' functions

Object based creation of step functions.

Still an experiment at this stage.

var StepObject = require('step-object'),
    fs = require('fs');

var ReadDir = StepObject({

  _filter: function(files){
    var filteredFiles;

    //some filter logic
    return filteredFiles;

  queue: function(path){
    fs.readdir(path, this);

  read: function(err, files){
      throw err;

    return this._filter(files);

}, ['queue', 'read']);

ReadDir(function(err, files){
  //files is the result of read

One problem I ran into using step initially was gaining access to the scope in which the steps actually execute in.

I still perfer to specify the behaviour of each function which becomes very difficult if these functions utlize the shared contex to store information.

The below will give you a reference to the the context the step execution. This is the same object you refer to when using 'this' inside of your step methods.

//Note that this will not call queue from the above example
var subject = require('step-object/lib/mock-step-object')(ReadDir);

subject.queue //

Its important for me to note that this works via a simple hack where by not returning anything in a function the step execution halts because its effectivly waiting for a callback to execute.

So if you did the following:

//(which is the same as `this()` or next inside of step scope)

It will cause werid things to happen such as two steps executing without waiting for the other to finish.

The .group and .parallel functions are overriden to return themselves. This is so you can spy for them inside of your tests.

You can also gain access to methods and order of the StepObject at anytime with:

ReadDir.methods //{queue: ....}
ReadDir.order //['queueRead', 'fsReadDir']