webpack/lib/dependencies/CommonJsRequireDependency.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports 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 Dependency = require("../Dependency");
const makeSerializable = require("../util/makeSerializable");
const {
	ESM_MODULE_EXPORTS_NAME,
	getRequireEsmModuleExportsAccess,
	isRequireEsmModuleExportsModule
} = require("./CommonJsDependencyHelpers");
const ModuleDependency = require("./ModuleDependency");

/** @typedef {import("webpack-sources").ReplaceSource} ReplaceSource */
/** @typedef {import("../Dependency").RawReferencedExports} RawReferencedExports */
/** @typedef {import("../Dependency").ReferencedExports} ReferencedExports */
/** @typedef {import("../DependencyTemplate").DependencyTemplateContext} DependencyTemplateContext */
/** @typedef {import("../Module")} Module */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */
/** @typedef {import("../util/runtime").RuntimeSpec} RuntimeSpec */

class CommonJsRequireDependency extends ModuleDependency {
	/**
	 * Creates an instance of CommonJsRequireDependency.
	 * @param {string} request request
	 * @param {Range=} range location in source code of the string-literal argument (gets replaced by the module id)
	 * @param {string=} context request context
	 * @param {RawReferencedExports | null=} referencedExports list of referenced exports
	 * @param {Range=} valueRange location in source code of the whole `require(...)` call (for `require(esm)` interop)
	 */
	constructor(
		request,
		range,
		context,
		referencedExports = null,
		valueRange = undefined
	) {
		super(request);
		this.range = range;
		this._context = context;
		this.referencedExports = referencedExports;
		this.valueRange = valueRange;
	}

	get type() {
		return "cjs require";
	}

	get category() {
		return "commonjs";
	}

	/**
	 * Returns list of exports referenced by this dependency
	 * @param {ModuleGraph} moduleGraph module graph
	 * @param {RuntimeSpec} runtime the runtime for which the module is analysed
	 * @returns {ReferencedExports} referenced exports
	 */
	getReferencedExports(moduleGraph, runtime) {
		const importedModule = moduleGraph.getModule(this);
		if (
			importedModule &&
			isRequireEsmModuleExportsModule(importedModule, moduleGraph)
		) {
			// `require(esm)` will unwrap the "module.exports" named export; only
			// that export is observable through this `require()` call.
			return [[ESM_MODULE_EXPORTS_NAME]];
		}
		if (!this.referencedExports) return Dependency.EXPORTS_OBJECT_REFERENCED;
		return this.referencedExports.map((name) => ({
			name,
			canMangle: false
		}));
	}

	/**
	 * Serializes this instance into the provided serializer context.
	 * @param {ObjectSerializerContext} context context
	 */
	serialize(context) {
		const { write } = context;
		write(this.referencedExports);
		write(this.valueRange);
		super.serialize(context);
	}

	/**
	 * Restores this instance from the provided deserializer context.
	 * @param {ObjectDeserializerContext} context context
	 */
	deserialize(context) {
		const { read } = context;
		this.referencedExports = read();
		this.valueRange = read();
		super.deserialize(context);
	}
}

CommonJsRequireDependency.Template = class CommonJsRequireDependencyTemplate extends (
	ModuleDependency.Template
) {
	/**
	 * Applies the plugin by registering its hooks on the compiler.
	 * @param {Dependency} dependency the dependency for which the template should be applied
	 * @param {ReplaceSource} source the current replace source which can be modified
	 * @param {DependencyTemplateContext} templateContext the context object
	 * @returns {void}
	 */
	apply(
		dependency,
		source,
		{ runtimeTemplate, moduleGraph, chunkGraph, runtime }
	) {
		const dep = /** @type {CommonJsRequireDependency} */ (dependency);
		if (!dep.range) return;
		const importedModule = /** @type {Module} */ (moduleGraph.getModule(dep));
		const content = runtimeTemplate.moduleId({
			module: importedModule,
			chunkGraph,
			request: dep.request,
			weak: dep.weak
		});
		source.replace(dep.range[0], dep.range[1] - 1, content);

		if (dep.valueRange && importedModule) {
			const access = getRequireEsmModuleExportsAccess(
				importedModule,
				moduleGraph,
				runtime
			);
			if (access !== null) {
				source.insert(dep.valueRange[1], access);
			}
		}
	}
};

makeSerializable(
	CommonJsRequireDependency,
	"webpack/lib/dependencies/CommonJsRequireDependency"
);

module.exports = CommonJsRequireDependency;