webpack/lib/NodeStuffPlugin.js

Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

const NodeStuffInWebError = require("./NodeStuffInWebError");
const RuntimeGlobals = require("./RuntimeGlobals");
const CachedConstDependency = require("./dependencies/CachedConstDependency");
const ConstDependency = require("./dependencies/ConstDependency");
const {
	evaluateToString,
	expressionIsUnsupported
} = require("./javascript/JavascriptParserHelpers");
const { relative } = require("./util/fs");
const { parseResource } = require("./util/identifier");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("./Compiler")} Compiler */
/** @typedef {import("./Dependency")} Dependency */
/** @typedef {import("./DependencyTemplates")} DependencyTemplates */
/** @typedef {import("./RuntimeTemplate")} RuntimeTemplate */

class NodeStuffPlugin {
	constructor(options) {
		this.options = options;
	}

	/**
	 * Apply the plugin
	 * @param {Compiler} compiler the compiler instance
	 * @returns {void}
	 */
	apply(compiler) {
		const options = this.options;
		compiler.hooks.compilation.tap(
			"NodeStuffPlugin",
			(compilation, { normalModuleFactory }) => {
				const handler = (parser, parserOptions) => {
					if (parserOptions.node === false) return;

					let localOptions = options;
					if (parserOptions.node) {
						localOptions = { ...localOptions, ...parserOptions.node };
					}

					if (localOptions.global !== false) {
						const withWarning = localOptions.global === "warn";
						parser.hooks.expression
							.for("global")
							.tap("NodeStuffPlugin", expr => {
								const dep = new ConstDependency(
									RuntimeGlobals.global,
									expr.range,
									[RuntimeGlobals.global]
								);
								dep.loc = expr.loc;
								parser.state.module.addPresentationalDependency(dep);

								// TODO webpack 6 remove
								if (withWarning) {
									parser.state.module.addWarning(
										new NodeStuffInWebError(
											dep.loc,
											"global",
											"The global namespace object is Node.js feature and doesn't present in browser."
										)
									);
								}
							});
					}

					const setModuleConstant = (expressionName, fn, warning) => {
						parser.hooks.expression
							.for(expressionName)
							.tap("NodeStuffPlugin", expr => {
								const dep = new CachedConstDependency(
									JSON.stringify(fn(parser.state.module)),
									expr.range,
									expressionName
								);
								dep.loc = expr.loc;
								parser.state.module.addPresentationalDependency(dep);

								// TODO webpack 6 remove
								if (warning) {
									parser.state.module.addWarning(
										new NodeStuffInWebError(dep.loc, expressionName, warning)
									);
								}

								return true;
							});
					};

					const setConstant = (expressionName, value, warning) =>
						setModuleConstant(expressionName, () => value, warning);

					const context = compiler.context;
					if (localOptions.__filename) {
						switch (localOptions.__filename) {
							case "mock":
								setConstant("__filename", "/index.js");
								break;
							case "warn-mock":
								setConstant(
									"__filename",
									"/index.js",
									"The __filename is Node.js feature and doesn't present in browser."
								);
								break;
							case true:
								setModuleConstant("__filename", module =>
									relative(compiler.inputFileSystem, context, module.resource)
								);
								break;
						}

						parser.hooks.evaluateIdentifier
							.for("__filename")
							.tap("NodeStuffPlugin", expr => {
								if (!parser.state.module) return;
								const resource = parseResource(parser.state.module.resource);
								return evaluateToString(resource.path)(expr);
							});
					}
					if (localOptions.__dirname) {
						switch (localOptions.__dirname) {
							case "mock":
								setConstant("__dirname", "/");
								break;
							case "warn-mock":
								setConstant(
									"__dirname",
									"/",
									"The __dirname is Node.js feature and doesn't present in browser."
								);
								break;
							case true:
								setModuleConstant("__dirname", module =>
									relative(compiler.inputFileSystem, context, module.context)
								);
								break;
						}

						parser.hooks.evaluateIdentifier
							.for("__dirname")
							.tap("NodeStuffPlugin", expr => {
								if (!parser.state.module) return;
								return evaluateToString(parser.state.module.context)(expr);
							});
					}
					parser.hooks.expression
						.for("require.extensions")
						.tap(
							"NodeStuffPlugin",
							expressionIsUnsupported(
								parser,
								"require.extensions is not supported by webpack. Use a loader instead."
							)
						);
				};

				normalModuleFactory.hooks.parser
					.for("javascript/auto")
					.tap("NodeStuffPlugin", handler);
				normalModuleFactory.hooks.parser
					.for("javascript/dynamic")
					.tap("NodeStuffPlugin", handler);
			}
		);
	}
}

module.exports = NodeStuffPlugin;