terser-webpack-plugin
Version:
Terser plugin for webpack
706 lines (658 loc) • 26.1 kB
JavaScript
;
const os = require("os");
const path = require("path");
const {
validate
} = require("schema-utils");
const {
minify
} = require("./minify");
const schema = require("./options.json");
const {
esbuildMinify,
memoize,
swcMinify,
terserMinify,
throttleAll,
uglifyJsMinify
} = require("./utils");
/** @typedef {import("schema-utils/declarations/validate").Schema} Schema */
/** @typedef {import("webpack").Compiler} Compiler */
/** @typedef {import("webpack").Compilation} Compilation */
/** @typedef {import("webpack").Configuration} Configuration */
/** @typedef {import("webpack").Asset} Asset */
/** @typedef {import("webpack").AssetInfo} AssetInfo */
/** @typedef {import("jest-worker").Worker} JestWorker */
/** @typedef {import("@jridgewell/trace-mapping").EncodedSourceMap & { sources: string[], sourcesContent?: string[], file: string }} RawSourceMap */
/** @typedef {import("@jridgewell/trace-mapping").TraceMap} TraceMap */
/** @typedef {RegExp | string} Rule */
/** @typedef {Rule[] | Rule} Rules */
// eslint-disable-next-line jsdoc/no-restricted-syntax
/**
* @callback ExtractCommentsFunction
* @param {any} astNode ast Node
* @param {{ value: string, type: 'comment1' | 'comment2' | 'comment3' | 'comment4', pos: number, line: number, col: number }} comment comment node
* @returns {boolean} true when need to extract comment, otherwise false
*/
/**
* @typedef {boolean | 'all' | 'some' | RegExp | ExtractCommentsFunction} ExtractCommentsCondition
*/
// eslint-disable-next-line jsdoc/no-restricted-syntax
/**
* @typedef {string | ((fileData: any) => string)} ExtractCommentsFilename
*/
/**
* @typedef {boolean | string | ((commentsFile: string) => string)} ExtractCommentsBanner
*/
/**
* @typedef {object} ExtractCommentsObject
* @property {ExtractCommentsCondition=} condition condition which comments need to be expected
* @property {ExtractCommentsFilename=} filename filename for extracted comments
* @property {ExtractCommentsBanner=} banner banner in filename for extracted comments
*/
/**
* @typedef {ExtractCommentsCondition | ExtractCommentsObject} ExtractCommentsOptions
*/
/**
* @typedef {object} ErrorObject
* @property {string} message message
* @property {number=} line line number
* @property {number=} column column number
* @property {string=} stack error stack trace
*/
/**
* @typedef {object} MinimizedResult
* @property {string=} code code
* @property {RawSourceMap=} map source map
* @property {Array<Error | string>=} errors errors
* @property {Array<Error | string>=} warnings warnings
* @property {Array<string>=} extractedComments extracted comments
*/
/**
* @typedef {{ [file: string]: string }} Input
*/
// eslint-disable-next-line jsdoc/no-restricted-syntax
/**
* @typedef {{ [key: string]: any }} CustomOptions
*/
/**
* @template T
* @typedef {T extends infer U ? U : CustomOptions} InferDefaultType
*/
/**
* @template T
* @typedef {object} PredefinedOptions
* @property {T extends { module?: infer P } ? P : boolean | string=} module true when code is a EC module, otherwise false
* @property {T extends { ecma?: infer P } ? P : number | string=} ecma ecma version
*/
/**
* @template T
* @typedef {PredefinedOptions<T> & InferDefaultType<T>} MinimizerOptions
*/
/**
* @template T
* @callback BasicMinimizerImplementation
* @param {Input} input
* @param {RawSourceMap | undefined} sourceMap
* @param {MinimizerOptions<T>} minifyOptions
* @param {ExtractCommentsOptions | undefined} extractComments
* @returns {Promise<MinimizedResult> | MinimizedResult}
*/
/**
* @typedef {object} MinimizeFunctionHelpers
* @property {() => string | undefined=} getMinimizerVersion function that returns version of minimizer
* @property {() => boolean | undefined=} supportsWorkerThreads true when minimizer support worker threads, otherwise false
*/
/**
* @template T
* @typedef {BasicMinimizerImplementation<T> & MinimizeFunctionHelpers} MinimizerImplementation
*/
/**
* @template T
* @typedef {object} InternalOptions
* @property {string} name name
* @property {string} input input
* @property {RawSourceMap | undefined} inputSourceMap input source map
* @property {ExtractCommentsOptions | undefined} extractComments extract comments option
* @property {{ implementation: MinimizerImplementation<T>, options: MinimizerOptions<T> }} minimizer minimizer
*/
/**
* @template T
* @typedef {JestWorker & { transform: (options: string) => Promise<MinimizedResult>, minify: (options: InternalOptions<T>) => Promise<MinimizedResult> }} MinimizerWorker
*/
/**
* @typedef {undefined | boolean | number} Parallel
*/
/**
* @typedef {object} BasePluginOptions
* @property {Rules=} test test rule
* @property {Rules=} include include rile
* @property {Rules=} exclude exclude rule
* @property {ExtractCommentsOptions=} extractComments extract comments options
* @property {Parallel=} parallel parallel option
*/
/**
* @template T
* @typedef {T extends import("terser").MinifyOptions ? { 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
*/
const getTraceMapping = memoize(() => require("@jridgewell/trace-mapping"));
const getSerializeJavascript = memoize(() => require("serialize-javascript"));
/**
* @template [T=import("terser").MinifyOptions]
*/
class TerserPlugin {
/**
* @param {BasePluginOptions & DefinedDefaultMinimizerAndOptions<T>=} options 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(\?.*)?$/i,
extractComments = true,
parallel = true,
include,
exclude
} = options || {};
/**
* @private
* @type {InternalPluginOptions<T>}
*/
this.options = {
test,
extractComments,
parallel,
include,
exclude,
minimizer: {
implementation: minify,
options: terserOptions
}
};
}
/**
* @private
* @param {unknown} input Input to check
* @returns {boolean} Whether input is a source map
*/
static isSourceMap(input) {
// All required options for `new TraceMap(...options)`
// https://github.com/jridgewell/trace-mapping#usage
return Boolean(input && typeof input === "object" && input !== null && "version" in input && "sources" in input && Array.isArray(input.sources) && "mappings" in input && typeof input.mappings === "string");
}
/**
* @private
* @param {unknown} warning warning
* @param {string} file file
* @returns {Error} built warning
*/
static buildWarning(warning, file) {
/**
* @type {Error & { hideStack: true, file: string }}
*/
// @ts-expect-error
const builtWarning = new Error(warning.toString());
builtWarning.name = "Warning";
builtWarning.hideStack = true;
builtWarning.file = file;
return builtWarning;
}
/**
* @private
* @param {Error | ErrorObject | string} error error
* @param {string} file file
* @param {TraceMap=} sourceMap source map
* @param {Compilation["requestShortener"]=} requestShortener request shortener
* @returns {Error} built error
*/
static buildError(error, file, sourceMap, requestShortener) {
/**
* @type {Error & { file?: string }}
*/
let builtError;
if (typeof error === "string") {
builtError = new Error(`${file} from Terser plugin\n${error}`);
builtError.file = file;
return builtError;
}
if ( /** @type {ErrorObject} */error.line) {
const {
line,
column
} = /** @type {ErrorObject & { line: number, column: number }} */error;
const original = sourceMap && getTraceMapping().originalPositionFor(sourceMap, {
line,
column
});
if (original && original.source && requestShortener) {
builtError = new Error(`${file} from Terser plugin\n${error.message} [${requestShortener.shorten(original.source)}:${original.line},${original.column}][${file}:${line},${column}]${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}:${line},${column}]${error.stack ? `\n${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 value of the `parallel` option
* @returns {number} number of cores for parallelism
*/
static getAvailableNumberOfCores(parallel) {
// In some cases cpus() returns undefined
// https://github.com/nodejs/node/issues/19022
const cpus =
// eslint-disable-next-line n/no-unsupported-features/node-builtins
typeof os.availableParallelism === "function" ?
// eslint-disable-next-line n/no-unsupported-features/node-builtins
{
length: os.availableParallelism()
} : os.cpus() || {
length: 1
};
return parallel === true || typeof parallel === "undefined" ? cpus.length - 1 : Math.min(parallel || 0, cpus.length - 1);
}
/**
* @private
* @param {Compiler} compiler compiler
* @param {Compilation} compilation compilation
* @param {Record<string, import("webpack").sources.Source>} assets assets
* @param {{ availableNumberOfCores: number }} optimizeOptions optimize options
* @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(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);
getWorker = () => {
if (initializedWorker) {
return initializedWorker;
}
const {
Worker
} = require("jest-worker");
initializedWorker = /** @type {MinimizerWorker<T>} */
new Worker(require.resolve("./minify"), {
numWorkers: numberOfWorkers,
enableWorkerThreads: typeof this.options.minimizer.implementation.supportsWorkerThreads !== "undefined" ? this.options.minimizer.implementation.supportsWorkerThreads() !== false : 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 {RawSourceMap | undefined} */
let inputSourceMap;
const {
source: sourceFromInputSource,
map
} = inputSource.sourceAndMap();
input = sourceFromInputSource;
if (map) {
if (!TerserPlugin.isSourceMap(map)) {
compilation.warnings.push(new Error(`${name} contains invalid source map`));
} else {
inputSourceMap = /** @type {RawSourceMap} */map;
}
}
if (Buffer.isBuffer(input)) {
input = input.toString();
}
/**
* @type {InternalOptions<T>}
*/
const options = {
name,
input,
inputSourceMap,
minimizer: {
implementation: this.options.minimizer.implementation,
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 = /** @type {PredefinedOptions<T>["module"]} */
info.javascriptModule;
} else if (/\.mjs(\?.*)?$/i.test(name)) {
options.minimizer.options.module = /** @type {PredefinedOptions<T>["module"]} */true;
} else if (/\.cjs(\?.*)?$/i.test(name)) {
options.minimizer.options.module = /** @type {PredefinedOptions<T>["module"]} */false;
}
}
if (typeof options.minimizer.options.ecma === "undefined") {
options.minimizer.options.ecma = /** @type {PredefinedOptions<T>["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(TerserPlugin.buildError( /** @type {Error | ErrorObject | string} */
error, name, hasSourceMap ? new (getTraceMapping().TraceMap)( /** @type {RawSourceMap} */
inputSourceMap) : undefined, hasSourceMap ? compilation.requestShortener : undefined));
return;
}
if (typeof output.code === "undefined") {
compilation.errors.push(new Error(`${name} from Terser plugin\nMinimizer doesn't return result`));
}
if (output.warnings && output.warnings.length > 0) {
output.warnings = output.warnings.map(
/**
* @param {Error | string} item a warning
* @returns {Error} built warning with extra info
*/
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 an error
* @returns {Error} built error with extra info
*/
item => TerserPlugin.buildError(item, name, hasSourceMap ? new (getTraceMapping().TraceMap)( /** @type {RawSourceMap} */
inputSourceMap) : undefined, hasSourceMap ? compilation.requestShortener : undefined));
}
// Custom functions can return `undefined` or `null`
if (typeof output.code !== "undefined" && output.code !== null) {
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.slice(0, Math.max(0, firstNewlinePosition));
output.code = output.code.slice(Math.max(0, firstNewlinePosition + 1));
}
if (output.map) {
output.source = new SourceMapSource(output.code, name, output.map, input, /** @type {RawSourceMap} */
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(warning);
}
}
if (output.errors && output.errors.length > 0) {
for (const error of output.errors) {
compilation.errors.push(error);
}
}
if (!output.source) {
return;
}
/** @type {AssetInfo} */
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 [...allExtractedComments].sort().reduce(
/**
* @param {Promise<unknown>} previousPromise previous result
* @param {[string, ExtractedCommentsInfo]} extractedComments extracted comments
* @returns {Promise<ExtractedCommentsInfoWithFrom>} extract comments with info
*/
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([...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 {NonNullable<NonNullable<Configuration["output"]>["environment"]>} environment environment
* @returns {number} ecma version
*/
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 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 {(text: string) => string} */green( /** @type {(flag: string) => string} */formatFlag("minimized")) : "");
});
});
}
}
TerserPlugin.terserMinify = terserMinify;
TerserPlugin.uglifyJsMinify = uglifyJsMinify;
TerserPlugin.swcMinify = swcMinify;
TerserPlugin.esbuildMinify = esbuildMinify;
module.exports = TerserPlugin;