constructor(defaults, options) {
    if (arguments.length === 0) {
      options = {};
    } else if (arguments.length === 1) {
      options = defaults;
    } else {
      defaultsDeep(options, defaults);
    }

    process.env.EMBER_ADDON_ENV = process.env.EMBER_ADDON_ENV || 'development';
    let overrides = {
      name: 'dummy',
      configPath: './tests/dummy/config/environment',
      trees: {
        app: 'tests/dummy/app',
        public: 'tests/dummy/public',
        styles: 'tests/dummy/app/styles',
        templates: 'tests/dummy/app/templates',
        tests: new Funnel('tests', {
          exclude: [/^dummy/],
        }),
        vendor: null,
      },
    };

    if (!fs.existsSync('tests/dummy/app')) {
      overrides.trees.app = null;
      overrides.trees.styles = null;
      overrides.trees.templates = null;
    }

    if (fs.existsSync('tests/dummy/vendor')) {
      overrides.trees.vendor = 'tests/dummy/vendor';
    }

    super(defaultsDeep(options, overrides));
  }
EmberAddon is used during addon development.

    @class EmberAddon
    @extends EmberApp
    @constructor
    @param {Object} [defaults]
    @param {Object} [options={}] Configuration options