/// <reference types="node" />
import * as Promise from 'bluebird';
import * as events from 'events';
import * as webpack from 'webpack';
declare type FilePath = string;
/**
 * Configuration object for this Webpack preprocessor
 */
interface PreprocessorOptions {
    webpackOptions?: webpack.Configuration;
    watchOptions?: Object;
    additionalEntries?: string[];
}
interface FileEvent extends events.EventEmitter {
    filePath: FilePath;
    outputPath: string;
    shouldWatch: boolean;
}
/**
 * Cypress asks file preprocessor to bundle the given file
 * and return the full path to produced bundle.
 */
declare type FilePreprocessor = (file: FileEvent) => Promise<FilePath>;
declare type WebpackPreprocessorFn = (options: PreprocessorOptions) => FilePreprocessor;
/**
 * Cypress file preprocessor that can bundle specs
 * using Webpack.
 */
interface WebpackPreprocessor extends WebpackPreprocessorFn {
    /**
     * Default options for Cypress Webpack preprocessor.
     * You can modify these options then pass to the preprocessor.
     * @example
      ```
      const defaults = webpackPreprocessor.defaultOptions
      module.exports = (on) => {
        delete defaults.webpackOptions.module.rules[0].use[0].options.presets
        on('file:preprocessor', webpackPreprocessor(defaults))
      }
      ```
     *
     * @type {Omit<PreprocessorOptions, 'additionalEntries'>}
     * @memberof WebpackPreprocessor
     */
    defaultOptions: Omit<PreprocessorOptions, 'additionalEntries'>;
}
/**
 * Webpack preprocessor configuration function. Takes configuration object
 * and returns file preprocessor.
 * @example
  ```
  on('file:preprocessor', webpackPreprocessor(options))
  ```
 */
declare const preprocessor: WebpackPreprocessor;
export = preprocessor;