mine/node_modules/terser-webpack-plugin/dist/index.js

"use strict";

const path = require("path");
const os = require("os");
const {
  validate
} = require("schema-utils");
const {
  throttleAll,
  terserMinify,
  uglifyJsMinify,
  swcMinify,
  esbuildMinify
} = require("./utils");
const schema = require("./options.json");
const {
  minify
} = require("./minify");

/** @typedef {import("schema-utils/declarations/validate").Schema} Schema */
/** @typedef {import("webpack").Compiler} Compiler */
/** @typedef {import("webpack").Compilation} Compilation */
/** @typedef {import("webpack").WebpackError} WebpackError */
/** @typedef {import("webpack").Asset} Asset */
/** @typedef {import("./utils.js").TerserECMA} TerserECMA */
/** @typedef {import("./utils.js").TerserOptions} TerserOptions */
/** @typedef {import("jest-worker").Worker} JestWorker */
/** @typedef {import("@jridgewell/trace-mapping").SourceMapInput} SourceMapInput */
/** @typedef {import("@jridgewell/trace-mapping").TraceMap} TraceMap */

/** @typedef {RegExp | string} Rule */
/** @typedef {Rule[] | Rule} Rules */

/**
 * @callback ExtractCommentsFunction
 * @param {any} astNode
 * @param {{ value: string, type: 'comment1' | 'comment2' | 'comment3' | 'comment4', pos: number, line: number, col: number }} comment
 * @returns {boolean}
 */

/**
 * @typedef {boolean | 'all' | 'some' | RegExp | ExtractCommentsFunction} ExtractCommentsCondition
 */

/**
 * @typedef {string | ((fileData: any) => string)} ExtractCommentsFilename
 */

/**
 * @typedef {boolean | string | ((commentsFile: string) => string)} ExtractCommentsBanner
 */

/**
 * @typedef {Object} ExtractCommentsObject
 * @property {ExtractCommentsCondition} [condition]
 * @property {ExtractCommentsFilename} [filename]
 * @property {ExtractCommentsBanner} [banner]
 */

/**
 * @typedef {ExtractCommentsCondition | ExtractCommentsObject} ExtractCommentsOptions
 */

/**
 * @typedef {Object} MinimizedResult
 * @property {string} code
 * @property {SourceMapInput} [map]
 * @property {Array<Error | string>} [errors]
 * @property {Array<Error | string>} [warnings]
 * @property {Array<string>} [extractedComments]
 */

/**
 * @typedef {{ [file: string]: string }} Input
 */

/**
 * @typedef {{ [key: string]: any }} CustomOptions
 */

/**
 * @template T
 * @typedef {T extends infer U ? U : CustomOptions} InferDefaultType
 */

/**
 * @typedef {Object} PredefinedOptions
 * @property {boolean} [module]
 * @property {TerserECMA} [ecma]
 */

/**
 * @template T
 * @typedef {PredefinedOptions & InferDefaultType<T>} MinimizerOptions
 */

/**
 * @template T
 * @callback BasicMinimizerImplementation
 * @param {Input} input
 * @param {SourceMapInput | undefined} sourceMap
 * @param {MinimizerOptions<T>} minifyOptions
 * @param {ExtractCommentsOptions | undefined} extractComments
 * @returns {Promise<MinimizedResult>}
 */

/**
 * @typedef {object} MinimizeFunctionHelpers
 * @property {() => string | undefined} [getMinimizerVersion]
 */

/**
 * @template T
 * @typedef {BasicMinimizerImplementation<T> & MinimizeFunctionHelpers} MinimizerImplementation
 */

/**
 * @template T
 * @typedef {Object} InternalOptions
 * @property {string} name
 * @property {string} input
 * @property {SourceMapInput | undefined} inputSourceMap
 * @property {ExtractCommentsOptions | undefined} extractComments
 * @property {{ implementation: MinimizerImplementation<T>, options: MinimizerOptions<T> }} minimizer
 */

/**
 * @template T
 * @typedef {JestWorker & { transform: (options: string) => MinimizedResult, minify: (options: InternalOptions<T>) => MinimizedResult }} MinimizerWorker
 */

/**
 * @typedef {undefined | boolean | number} Parallel
 */

/**
 * @typedef {Object} BasePluginOptions
 * @property {Rules} [test]
 * @property {Rules} [include]
 * @property {Rules} [exclude]
 * @property {ExtractCommentsOptions} [extractComments]
 * @property {Parallel} [parallel]
 */

/**
 * @template T
 * @typedef {T extends TerserOptions ? { minify?: MinimizerImplementation<T> | undefined, terserOptions?: MinimizerOptions<T> | undefined } : { minify: MinimizerImplementation<T>, terserOptions?: MinimizerOptions<T> | undefined }} DefinedDefaultMinimizerAndOptions
 */

/**
 * @template T
 * @typedef {BasePluginOptions & { minimizer: { implementation: MinimizerImplementation<T>, options: MinimizerOptions<T> } }} InternalPluginOptions
 */

/**
 * @template T
 * @param fn {(function(): any) | undefined}
 * @returns {function(): T}
 */
const memoize = fn => {
  let cache = false;
  /** @type {T} */
  let result;
  return () => {
    if (cache) {
      return result;
    }
    result = /** @type {function(): any} */fn();
    cache = true;
    // Allow to clean up memory for fn
    // and all dependent resources
    // eslint-disable-next-line no-undefined, no-param-reassign
    fn = undefined;
    return result;
  };
};
const getTraceMapping = memoize(() =>
// eslint-disable-next-line global-require
require("@jridgewell/trace-mapping"));
const getSerializeJavascript = memoize(() =>
// eslint-disable-next-line global-require
require("serialize-javascript"));

/**
 * @template [T=TerserOptions]
 */
class TerserPlugin {
  /**
   * @param {BasePluginOptions & DefinedDefaultMinimizerAndOptions<T>} [options]
   */
  constructor(options) {
    validate( /** @type {Schema} */schema, options || {}, {
      name: "Terser Plugin",
      baseDataPath: "options"
    });

    // TODO make `minimizer` option instead `minify` and `terserOptions` in the next major release, also rename `terserMinify` to `terserMinimize`
    const {
      minify = /** @type {MinimizerImplementation<T>} */terserMinify,
      terserOptions = /** @type {MinimizerOptions<T>} */{},
      test = /\.[cm]?js(\?.*)?$/i,
      extractComments = true,
      parallel = true,
      include,
      exclude
    } = options || {};

    /**
     * @private
     * @type {InternalPluginOptions<T>}
     */
    this.options = {
      test,
      extractComments,
      parallel,
      include,
      exclude,
      minimizer: {
        implementation: minify,
        options: terserOptions
      }
    };
  }

  /**
   * @private
   * @param {any} input
   * @returns {boolean}
   */
  static isSourceMap(input) {
    // All required options for `new TraceMap(...options)`
    // https://github.com/jridgewell/trace-mapping#usage
    return Boolean(input && input.version && input.sources && Array.isArray(input.sources) && typeof input.mappings === "string");
  }

  /**
   * @private
   * @param {unknown} warning
   * @param {string} file
   * @returns {Error}
   */
  static buildWarning(warning, file) {
    /**
     * @type {Error & { hideStack: true, file: string }}
     */
    // @ts-ignore
    const builtWarning = new Error(warning.toString());
    builtWarning.name = "Warning";
    builtWarning.hideStack = true;
    builtWarning.file = file;
    return builtWarning;
  }

  /**
   * @private
   * @param {any} error
   * @param {string} file
   * @param {TraceMap} [sourceMap]
   * @param {Compilation["requestShortener"]} [requestShortener]
   * @returns {Error}
   */
  static buildError(error, file, sourceMap, requestShortener) {
    /**
     * @type {Error & { file?: string }}
     */
    let builtError;
    if (typeof error === "string") {
      builtError = new Error(`${file} from Terser plugin\n${error}`);
      builtError.file = file;
      return builtError;
    }
    if (error.line) {
      const original = sourceMap && getTraceMapping().originalPositionFor(sourceMap, {
        line: error.line,
        column: error.col
      });
      if (original && original.source && requestShortener) {
        builtError = new Error(`${file} from Terser plugin\n${error.message} [${requestShortener.shorten(original.source)}:${original.line},${original.column}][${file}:${error.line},${error.col}]${error.stack ? `\n${error.stack.split("\n").slice(1).join("\n")}` : ""}`);
        builtError.file = file;
        return builtError;
      }
      builtError = new Error(`${file} from Terser plugin\n${error.message} [${file}:${error.line},${error.col}]${error.stack ? `\n${error.stack.split("\n").slice(1).join("\n")}` : ""}`);
      builtError.file = file;
      return builtError;
    }
    if (error.stack) {
      builtError = new Error(`${file} from Terser plugin\n${typeof error.message !== "undefined" ? error.message : ""}\n${error.stack}`);
      builtError.file = file;
      return builtError;
    }
    builtError = new Error(`${file} from Terser plugin\n${error.message}`);
    builtError.file = file;
    return builtError;
  }

  /**
   * @private
   * @param {Parallel} parallel
   * @returns {number}
   */
  static getAvailableNumberOfCores(parallel) {
    // In some cases cpus() returns undefined
    // https://github.com/nodejs/node/issues/19022
    const cpus = os.cpus() || {
      length: 1
    };
    return parallel === true ? cpus.length - 1 : Math.min(Number(parallel) || 0, cpus.length - 1);
  }

  /**
   * @private
   * @param {Compiler} compiler
   * @param {Compilation} compilation
   * @param {Record<string, import("webpack").sources.Source>} assets
   * @param {{availableNumberOfCores: number}} optimizeOptions
   * @returns {Promise<void>}
   */
  async optimize(compiler, compilation, assets, optimizeOptions) {
    const cache = compilation.getCache("TerserWebpackPlugin");
    let numberOfAssets = 0;
    const assetsForMinify = await Promise.all(Object.keys(assets).filter(name => {
      const {
        info
      } = /** @type {Asset} */compilation.getAsset(name);
      if (
      // Skip double minimize assets from child compilation
      info.minimized ||
      // Skip minimizing for extracted comments assets
      info.extractedComments) {
        return false;
      }
      if (!compiler.webpack.ModuleFilenameHelpers.matchObject.bind(
      // eslint-disable-next-line no-undefined
      undefined, this.options)(name)) {
        return false;
      }
      return true;
    }).map(async name => {
      const {
        info,
        source
      } = /** @type {Asset} */
      compilation.getAsset(name);
      const eTag = cache.getLazyHashedEtag(source);
      const cacheItem = cache.getItemCache(name, eTag);
      const output = await cacheItem.getPromise();
      if (!output) {
        numberOfAssets += 1;
      }
      return {
        name,
        info,
        inputSource: source,
        output,
        cacheItem
      };
    }));
    if (assetsForMinify.length === 0) {
      return;
    }

    /** @type {undefined | (() => MinimizerWorker<T>)} */
    let getWorker;
    /** @type {undefined | MinimizerWorker<T>} */
    let initializedWorker;
    /** @type {undefined | number} */
    let numberOfWorkers;
    if (optimizeOptions.availableNumberOfCores > 0) {
      // Do not create unnecessary workers when the number of files is less than the available cores, it saves memory
      numberOfWorkers = Math.min(numberOfAssets, optimizeOptions.availableNumberOfCores);
      // eslint-disable-next-line consistent-return
      getWorker = () => {
        if (initializedWorker) {
          return initializedWorker;
        }

        // eslint-disable-next-line global-require
        const {
          Worker
        } = require("jest-worker");
        initializedWorker = /** @type {MinimizerWorker<T>} */

        new Worker(require.resolve("./minify"), {
          numWorkers: numberOfWorkers,
          enableWorkerThreads: true
        });

        // https://github.com/facebook/jest/issues/8872#issuecomment-524822081
        const workerStdout = initializedWorker.getStdout();
        if (workerStdout) {
          workerStdout.on("data", chunk => process.stdout.write(chunk));
        }
        const workerStderr = initializedWorker.getStderr();
        if (workerStderr) {
          workerStderr.on("data", chunk => process.stderr.write(chunk));
        }
        return initializedWorker;
      };
    }
    const {
      SourceMapSource,
      ConcatSource,
      RawSource
    } = compiler.webpack.sources;

    /** @typedef {{ extractedCommentsSource : import("webpack").sources.RawSource, commentsFilename: string }} ExtractedCommentsInfo */
    /** @type {Map<string, ExtractedCommentsInfo>} */
    const allExtractedComments = new Map();
    const scheduledTasks = [];
    for (const asset of assetsForMinify) {
      scheduledTasks.push(async () => {
        const {
          name,
          inputSource,
          info,
          cacheItem
        } = asset;
        let {
          output
        } = asset;
        if (!output) {
          let input;
          /** @type {SourceMapInput | undefined} */
          let inputSourceMap;
          const {
            source: sourceFromInputSource,
            map
          } = inputSource.sourceAndMap();
          input = sourceFromInputSource;
          if (map) {
            if (!TerserPlugin.isSourceMap(map)) {
              compilation.warnings.push( /** @type {WebpackError} */
              new Error(`${name} contains invalid source map`));
            } else {
              inputSourceMap = /** @type {SourceMapInput} */map;
            }
          }
          if (Buffer.isBuffer(input)) {
            input = input.toString();
          }

          /**
           * @type {InternalOptions<T>}
           */
          const options = {
            name,
            input,
            inputSourceMap,
            minimizer: {
              implementation: this.options.minimizer.implementation,
              // @ts-ignore https://github.com/Microsoft/TypeScript/issues/10727
              options: {
                ...this.options.minimizer.options
              }
            },
            extractComments: this.options.extractComments
          };
          if (typeof options.minimizer.options.module === "undefined") {
            if (typeof info.javascriptModule !== "undefined") {
              options.minimizer.options.module = info.javascriptModule;
            } else if (/\.mjs(\?.*)?$/i.test(name)) {
              options.minimizer.options.module = true;
            } else if (/\.cjs(\?.*)?$/i.test(name)) {
              options.minimizer.options.module = false;
            }
          }
          if (typeof options.minimizer.options.ecma === "undefined") {
            options.minimizer.options.ecma = TerserPlugin.getEcmaVersion(compiler.options.output.environment || {});
          }
          try {
            output = await (getWorker ? getWorker().transform(getSerializeJavascript()(options)) : minify(options));
          } catch (error) {
            const hasSourceMap = inputSourceMap && TerserPlugin.isSourceMap(inputSourceMap);
            compilation.errors.push( /** @type {WebpackError} */

            TerserPlugin.buildError(error, name, hasSourceMap ? new (getTraceMapping().TraceMap)( /** @type {SourceMapInput} */inputSourceMap) :
            // eslint-disable-next-line no-undefined
            undefined,
            // eslint-disable-next-line no-undefined
            hasSourceMap ? compilation.requestShortener : undefined));
            return;
          }
          if (typeof output.code === "undefined") {
            compilation.errors.push( /** @type {WebpackError} */

            new Error(`${name} from Terser plugin\nMinimizer doesn't return result`));
            return;
          }
          if (output.warnings && output.warnings.length > 0) {
            output.warnings = output.warnings.map(
            /**
             * @param {Error | string} item
             */
            item => TerserPlugin.buildWarning(item, name));
          }
          if (output.errors && output.errors.length > 0) {
            const hasSourceMap = inputSourceMap && TerserPlugin.isSourceMap(inputSourceMap);
            output.errors = output.errors.map(
            /**
             * @param {Error | string} item
             */
            item => TerserPlugin.buildError(item, name, hasSourceMap ? new (getTraceMapping().TraceMap)( /** @type {SourceMapInput} */inputSourceMap) :
            // eslint-disable-next-line no-undefined
            undefined,
            // eslint-disable-next-line no-undefined
            hasSourceMap ? compilation.requestShortener : undefined));
          }
          let shebang;
          if ( /** @type {ExtractCommentsObject} */
          this.options.extractComments.banner !== false && output.extractedComments && output.extractedComments.length > 0 && output.code.startsWith("#!")) {
            const firstNewlinePosition = output.code.indexOf("\n");
            shebang = output.code.substring(0, firstNewlinePosition);
            output.code = output.code.substring(firstNewlinePosition + 1);
          }
          if (output.map) {
            output.source = new SourceMapSource(output.code, name, output.map, input, /** @type {SourceMapInput} */inputSourceMap, true);
          } else {
            output.source = new RawSource(output.code);
          }
          if (output.extractedComments && output.extractedComments.length > 0) {
            const commentsFilename = /** @type {ExtractCommentsObject} */
            this.options.extractComments.filename || "[file].LICENSE.txt[query]";
            let query = "";
            let filename = name;
            const querySplit = filename.indexOf("?");
            if (querySplit >= 0) {
              query = filename.slice(querySplit);
              filename = filename.slice(0, querySplit);
            }
            const lastSlashIndex = filename.lastIndexOf("/");
            const basename = lastSlashIndex === -1 ? filename : filename.slice(lastSlashIndex + 1);
            const data = {
              filename,
              basename,
              query
            };
            output.commentsFilename = compilation.getPath(commentsFilename, data);
            let banner;

            // Add a banner to the original file
            if ( /** @type {ExtractCommentsObject} */
            this.options.extractComments.banner !== false) {
              banner = /** @type {ExtractCommentsObject} */
              this.options.extractComments.banner || `For license information please see ${path.relative(path.dirname(name), output.commentsFilename).replace(/\\/g, "/")}`;
              if (typeof banner === "function") {
                banner = banner(output.commentsFilename);
              }
              if (banner) {
                output.source = new ConcatSource(shebang ? `${shebang}\n` : "", `/*! ${banner} */\n`, output.source);
              }
            }
            const extractedCommentsString = output.extractedComments.sort().join("\n\n");
            output.extractedCommentsSource = new RawSource(`${extractedCommentsString}\n`);
          }
          await cacheItem.storePromise({
            source: output.source,
            errors: output.errors,
            warnings: output.warnings,
            commentsFilename: output.commentsFilename,
            extractedCommentsSource: output.extractedCommentsSource
          });
        }
        if (output.warnings && output.warnings.length > 0) {
          for (const warning of output.warnings) {
            compilation.warnings.push( /** @type {WebpackError} */warning);
          }
        }
        if (output.errors && output.errors.length > 0) {
          for (const error of output.errors) {
            compilation.errors.push( /** @type {WebpackError} */error);
          }
        }

        /** @type {Record<string, any>} */
        const newInfo = {
          minimized: true
        };
        const {
          source,
          extractedCommentsSource
        } = output;

        // Write extracted comments to commentsFilename
        if (extractedCommentsSource) {
          const {
            commentsFilename
          } = output;
          newInfo.related = {
            license: commentsFilename
          };
          allExtractedComments.set(name, {
            extractedCommentsSource,
            commentsFilename
          });
        }
        compilation.updateAsset(name, source, newInfo);
      });
    }
    const limit = getWorker && numberOfAssets > 0 ? /** @type {number} */numberOfWorkers : scheduledTasks.length;
    await throttleAll(limit, scheduledTasks);
    if (initializedWorker) {
      await initializedWorker.end();
    }

    /** @typedef {{ source: import("webpack").sources.Source, commentsFilename: string, from: string }} ExtractedCommentsInfoWIthFrom */
    await Array.from(allExtractedComments).sort().reduce(
    /**
     * @param {Promise<unknown>} previousPromise
     * @param {[string, ExtractedCommentsInfo]} extractedComments
     * @returns {Promise<ExtractedCommentsInfoWIthFrom>}
     */
    async (previousPromise, [from, value]) => {
      const previous = /** @type {ExtractedCommentsInfoWIthFrom | undefined} **/
      await previousPromise;
      const {
        commentsFilename,
        extractedCommentsSource
      } = value;
      if (previous && previous.commentsFilename === commentsFilename) {
        const {
          from: previousFrom,
          source: prevSource
        } = previous;
        const mergedName = `${previousFrom}|${from}`;
        const name = `${commentsFilename}|${mergedName}`;
        const eTag = [prevSource, extractedCommentsSource].map(item => cache.getLazyHashedEtag(item)).reduce((previousValue, currentValue) => cache.mergeEtags(previousValue, currentValue));
        let source = await cache.getPromise(name, eTag);
        if (!source) {
          source = new ConcatSource(Array.from(new Set([... /** @type {string}*/prevSource.source().split("\n\n"), ... /** @type {string}*/extractedCommentsSource.source().split("\n\n")])).join("\n\n"));
          await cache.storePromise(name, eTag, source);
        }
        compilation.updateAsset(commentsFilename, source);
        return {
          source,
          commentsFilename,
          from: mergedName
        };
      }
      const existingAsset = compilation.getAsset(commentsFilename);
      if (existingAsset) {
        return {
          source: existingAsset.source,
          commentsFilename,
          from: commentsFilename
        };
      }
      compilation.emitAsset(commentsFilename, extractedCommentsSource, {
        extractedComments: true
      });
      return {
        source: extractedCommentsSource,
        commentsFilename,
        from
      };
    }, /** @type {Promise<unknown>} */Promise.resolve());
  }

  /**
   * @private
   * @param {any} environment
   * @returns {TerserECMA}
   */
  static getEcmaVersion(environment) {
    // ES 6th
    if (environment.arrowFunction || environment.const || environment.destructuring || environment.forOf || environment.module) {
      return 2015;
    }

    // ES 11th
    if (environment.bigIntLiteral || environment.dynamicImport) {
      return 2020;
    }
    return 5;
  }

  /**
   * @param {Compiler} compiler
   * @returns {void}
   */
  apply(compiler) {
    const pluginName = this.constructor.name;
    const availableNumberOfCores = TerserPlugin.getAvailableNumberOfCores(this.options.parallel);
    compiler.hooks.compilation.tap(pluginName, compilation => {
      const hooks = compiler.webpack.javascript.JavascriptModulesPlugin.getCompilationHooks(compilation);
      const data = getSerializeJavascript()({
        minimizer: typeof this.options.minimizer.implementation.getMinimizerVersion !== "undefined" ? this.options.minimizer.implementation.getMinimizerVersion() || "0.0.0" : "0.0.0",
        options: this.options.minimizer.options
      });
      hooks.chunkHash.tap(pluginName, (chunk, hash) => {
        hash.update("TerserPlugin");
        hash.update(data);
      });
      compilation.hooks.processAssets.tapPromise({
        name: pluginName,
        stage: compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_OPTIMIZE_SIZE,
        additionalAssets: true
      }, assets => this.optimize(compiler, compilation, assets, {
        availableNumberOfCores
      }));
      compilation.hooks.statsPrinter.tap(pluginName, stats => {
        stats.hooks.print.for("asset.info.minimized").tap("terser-webpack-plugin", (minimized, {
          green,
          formatFlag
        }) => minimized ? /** @type {Function} */green( /** @type {Function} */formatFlag("minimized")) : "");
      });
    });
  }
}
TerserPlugin.terserMinify = terserMinify;
TerserPlugin.uglifyJsMinify = uglifyJsMinify;
TerserPlugin.swcMinify = swcMinify;
TerserPlugin.esbuildMinify = esbuildMinify;
module.exports = TerserPlugin;