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'use strict';
const PromiseProvider = require('../promise_provider');const immediate = require('./immediate');
const emittedSymbol = Symbol('mongoose:emitted');
module.exports = function promiseOrCallback(callback, fn, ee, Promise) {  if (typeof callback === 'function') {    try {      return fn(function(error) {        if (error != null) {          if (ee != null && ee.listeners != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {            error[emittedSymbol] = true;            ee.emit('error', error);          }          try {            callback(error);          } catch (error) {            return immediate(() => {              throw error;            });          }          return;        }        callback.apply(this, arguments);      });    } catch (error) {      if (ee != null && ee.listeners != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {        error[emittedSymbol] = true;        ee.emit('error', error);      }
      return callback(error);    }  }
  Promise = Promise || PromiseProvider.get();
  return new Promise((resolve, reject) => {    fn(function(error, res) {      if (error != null) {        if (ee != null && ee.listeners != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {          error[emittedSymbol] = true;          ee.emit('error', error);        }        return reject(error);      }      if (arguments.length > 2) {        return resolve(Array.prototype.slice.call(arguments, 1));      }      resolve(res);    });  });};