Make the Marionette.NextCollectionView act like a CompositeView

make-composite.js

/*
 *  To use:
 *  Mn.NextCollectionView.extend({
 *    initialize() {
 *      new MakeComposite({ el: this.el, collectionView: this });
 *    }
 *    // Regular CompositeView API
 *  });
 *
 */

import _ from 'underscore';
import Marionette from 'backbone.marionette';

const CompositeOptions = [
    'childViewContainer',
    'collection',
    'model',
    'template',
    'templateContext'
];

const MakeCompositeView = Marionette.View.extend({
  initialize(options) {
    this.mergeOptions(options, ['collectionView']);
    _.extend(this.options, this.collectionView.options);
    _.each(CompositeOptions, opt => {
       this[opt] = this.collectionView.getOption(opt);
    });

    this.listenTo(this.collectionView, {
      'before:render': this.onBeforeRenderCollectionView,
      'before:destroy': this.onBeforeDestroyCollectionView
    });
    this.collectionView.attachHtml = _.bind(this._attachHtml, this);
    if(!this.collectionView.childView) {
      this.collectionView.childView = this.collectionView;
    }
  },
  _attachHtml(els) {
      this.Dom.appendContents(this.$container[0], els, {_$el: this.$container});
  },
  onBeforeRenderCollectionView() {
    this.render();
    this.collectionView.bindUIElements();
    this.getChildViewContainer();
  },
  getChildViewContainer() {
    const childViewContainer = _.result(this.collectionView, 'childViewContainer');
    this.$container = childViewContainer ? this.$(childViewContainer) : this.$el;
  },
  onBeforeDestroyCollectionView() {
    this.destroy();
  }
});

export default function(collectionView) {
   new MakeCompositeView({ el: collectionView.el, collectionView }); 
}