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 a Node.js feature and isn't available in browsers."
										)
									);
								}
							});
						parser.hooks.rename.for("global").tap("NodeStuffPlugin", expr => {
							const dep = new ConstDependency(
								RuntimeGlobals.global,
								expr.range,
								[RuntimeGlobals.global]
							);
							dep.loc = expr.loc;
							parser.state.module.addPresentationalDependency(dep);
							return false;
						});
					}

					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",
									"__filename is a Node.js feature and isn't available in browsers."
								);
								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",
									"/",
									"__dirname is a Node.js feature and isn't available in browsers."
								);
								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;