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 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) {
						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);
							});
					}

					const setModuleConstant = (expressionName, fn) => {
						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);
								return true;
							});
					};

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

					const context = compiler.context;
					if (localOptions.__filename) {
						if (localOptions.__filename === "mock") {
							setConstant("__filename", "/index.js");
						} else if (localOptions.__filename === true) {
							setModuleConstant("__filename", module =>
								relative(compiler.inputFileSystem, context, module.resource)
							);
						}
						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) {
						if (localOptions.__dirname === "mock") {
							setConstant("__dirname", "/");
						} else if (localOptions.__dirname === true) {
							setModuleConstant("__dirname", module =>
								relative(compiler.inputFileSystem, context, module.context)
							);
						}
						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;