webpack/lib/dependencies/ContextDependency.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 DependencyTemplate = require("../DependencyTemplate");
const makeSerializable = require("../util/makeSerializable");
const memoize = require("../util/memoize");

/** @typedef {import("../javascript/JavascriptParser").Range} Range */
/** @typedef {import("../ContextModule").ContextOptions} ContextOptions */
/** @typedef {import("../Dependency").TRANSITIVE} TRANSITIVE */
/** @typedef {import("../ModuleGraph")} ModuleGraph */
/** @typedef {import("../WebpackError")} WebpackError */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectDeserializerContext} ObjectDeserializerContext */
/** @typedef {import("../serialization/ObjectMiddleware").ObjectSerializerContext} ObjectSerializerContext */

const getCriticalDependencyWarning = memoize(() =>
	require("./CriticalDependencyWarning")
);

/** @typedef {ContextOptions & { request: string }} ContextDependencyOptions */

/** @typedef {{ value: string, range: Range }[]} Replaces */

/**
 * Returns stringified regexp.
 * @param {RegExp | false | null | undefined} r regexp
 * @returns {string} stringified regexp
 */
const regExpToString = (r) => (r ? String(r) : "");

class ContextDependency extends Dependency {
	/**
	 * Creates an instance of ContextDependency.
	 * @param {ContextDependencyOptions} options options for the context module
	 * @param {string=} context request context
	 */
	constructor(options, context) {
		super();

		this.options = options;
		this.userRequest = this.options && this.options.request;
		/** @type {false | undefined | string} */
		this.critical = false;
		this.hadGlobalOrStickyRegExp = false;

		if (
			this.options &&
			this.options.regExp &&
			(this.options.regExp.global || this.options.regExp.sticky)
		) {
			this.options = { ...this.options, regExp: null };
			this.hadGlobalOrStickyRegExp = true;
		}

		/** @type {string | undefined} */
		this.request = undefined;
		/** @type {Range | undefined} */
		this.range = undefined;
		/** @type {Range | undefined} */
		this.valueRange = undefined;
		/** @type {boolean | string | undefined} */
		this.inShorthand = undefined;
		/** @type {Replaces | undefined} */
		this.replaces = undefined;
		this._requestContext = context;
	}

	/**
	 * Returns a request context.
	 * @returns {string | undefined} a request context
	 */
	getContext() {
		return this._requestContext;
	}

	get category() {
		return "commonjs";
	}

	/**
	 * Could affect referencing module.
	 * @returns {boolean | TRANSITIVE} true, when changes to the referenced module could affect the referencing module; TRANSITIVE, when changes to the referenced module could affect referencing modules of the referencing module
	 */
	couldAffectReferencingModule() {
		return true;
	}

	/**
	 * Returns an identifier to merge equal requests.
	 * @returns {string | null} an identifier to merge equal requests
	 */
	getResourceIdentifier() {
		return (
			`context${this._requestContext || ""}|ctx request${
				this.options.request
			} ${this.options.recursive} ` +
			`${regExpToString(this.options.regExp)} ${regExpToString(
				this.options.include
			)} ${regExpToString(this.options.exclude)} ` +
			`${this.options.mode} ${this.options.chunkName} ` +
			`${JSON.stringify(this.options.groupOptions)}` +
			`${
				this.options.referencedExports
					? ` ${JSON.stringify(this.options.referencedExports)}`
					: ""
			}`
		);
	}

	/**
	 * Returns warnings.
	 * @param {ModuleGraph} moduleGraph module graph
	 * @returns {WebpackError[] | null | undefined} warnings
	 */
	getWarnings(moduleGraph) {
		let warnings = super.getWarnings(moduleGraph);

		if (this.critical) {
			if (!warnings) warnings = [];
			const CriticalDependencyWarning = getCriticalDependencyWarning();
			warnings.push(new CriticalDependencyWarning(this.critical));
		}

		if (this.hadGlobalOrStickyRegExp) {
			if (!warnings) warnings = [];
			const CriticalDependencyWarning = getCriticalDependencyWarning();
			warnings.push(
				new CriticalDependencyWarning(
					"Contexts can't use RegExps with the 'g' or 'y' flags."
				)
			);
		}

		return warnings;
	}

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

		write(this.options);
		write(this.userRequest);
		write(this.critical);
		write(this.hadGlobalOrStickyRegExp);
		write(this.request);
		write(this._requestContext);
		write(this.range);
		write(this.valueRange);
		write(this.replaces);

		super.serialize(context);
	}

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

		this.options = read();
		this.userRequest = read();
		this.critical = read();
		this.hadGlobalOrStickyRegExp = read();
		this.request = read();
		this._requestContext = read();
		this.range = read();
		this.valueRange = read();
		this.replaces = read();

		super.deserialize(context);
	}
}

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

ContextDependency.Template = DependencyTemplate;

module.exports = ContextDependency;