old_contents: 'use strict';
  const path = require('path');
  const assert = require('assert');
  const fs = require('fs');
  
  module.exports = {
    name: require('./package').name,
    included() {
      const app = this._findHost();
      const addonConfig = this.app.project.config(app.env)['orbit'] || {};
      const collections = addonConfig.collections || {};
      let modelsPath;
  
      if (collections.models) {
        modelsPath = path.join('app', collections.models);
      } else if (
        app.project.pkg['ember-addon'] &&
        app.project.pkg['ember-addon'].configPath
      ) {
        modelsPath = path.join('tests', 'dummy', 'app', 'data-models');
      } else {
        modelsPath = path.join('app', 'data-models');
      }
  
      const modelsDirectory = path.join(app.project.root, modelsPath);
  
      assert(
        fs.existsSync(modelsDirectory),
        `You need to create models directory: "${modelsDirectory}"`
      );
  
      this._super.included.apply(this, arguments);
    }
  };
  
new_contents: 'use strict';
  const path = require('path');
  const assert = require('assert');
  const fs = require('fs');
  
  module.exports = {
    name: require('./package').name,
    included() {
      const app = this._findHost();
      const addonConfig = this.app.project.config(app.env)['orbit'] || {};
      const collections = addonConfig.collections || {};
      const modelsDir = collections.models || 'data-models';
      let modelsPath;
  
      if (
        app.project.pkg['ember-addon'] &&
        app.project.pkg['ember-addon'].configPath
      ) {
        modelsPath = path.join('tests', 'dummy', 'app', modelsDir);
      } else {
        modelsPath = path.join('app', modelsDir);
      }
  
      const modelsDirectory = path.join(app.project.root, modelsPath);
  
      assert(
        fs.existsSync(modelsDirectory),
        `[ember-orbit] The models directory is missing: "${modelsDirectory}". You can run 'ember g ember-orbit' to initialize ember-orbit and create this directory.`
      );
  
      this._super.included.apply(this, arguments);
    }
  };
  
subject: Improve initial check for `data-models` dir