build.js

/**
 * Modified `build` to encapsulate state in a `Build` object...
 */

Builder.prototype.build = function (fn) {
  var self = this;
  this.lookup.end(function (err, components) {
    if (err) return fn(err);
    self.build = new Build(components);
    self.batch.end(function (err) {
      if (err) return fn(err);
      fn(null, self.build);
    });
  })
};

/**
 * Initialize a new build with a `components` of components.
 * 
 * @param {Array} components
 */
 
function Build (components) {
  this.components = components;
}

/**
 * Loop through each of the components by `type`.
 * 
 * @param {String} type
 * @param {Function} fn
 */
 
Build.prototype.each = function (type, fn) {
  for (var i = 0; i < this.components.length; ++i) {
    var files = this.components[i][type] || [];
    for (var j = 0; j < files.length; ++j) {
      fn(files[j], this.components[i]);
    }
  }
};

/**
 * Map each of the components by `type`.
 * 
 * @param {String} type
 * @param {Function} fn
 */
 
Build.prototype.map = function (type, fn) {
  for (var i = 0; i < this.components.length; ++i) {
    var files = this.components[i][type] || [];
    for (var j = 0; j < files.length; ++j) {
      files[j] = fn(files[j], this.components[i]);
    }
  }
};