overleaf/services/web/frontend/js/ide/file-tree/controllers/FileTreeController.js

import App from '../../../base'
App.controller('FileTreeController', [
  '$scope',
  function ($scope) {
    $scope.openNewDocModal = () => {
      window.dispatchEvent(
        new CustomEvent('file-tree.start-creating', { detail: { mode: 'doc' } })
      )
    }

    $scope.orderByFoldersFirst = function (entity) {
      if ((entity != null ? entity.type : undefined) === 'folder') {
        return '0'
      }
      return '1'
    }
  },
])