webpack/lib/dependencies/LocalModulesHelpers.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 LocalModule = require("./LocalModule");

/** @typedef {import("../javascript/JavascriptParser").JavascriptParserState} JavascriptParserState */

/**
 * Returns resolved module.
 * @param {string} parent parent module
 * @param {string} mod module to resolve
 * @returns {string} resolved module
 */
const lookup = (parent, mod) => {
	if (mod.charAt(0) !== ".") return mod;

	const path = parent.split("/");
	const segments = mod.split("/");
	path.pop();

	for (let i = 0; i < segments.length; i++) {
		const seg = segments[i];
		if (seg === "..") {
			path.pop();
		} else if (seg !== ".") {
			path.push(seg);
		}
	}

	return path.join("/");
};

/**
 * Returns local module.
 * @param {JavascriptParserState} state parser state
 * @param {string} name name
 * @returns {LocalModule} local module
 */
module.exports.addLocalModule = (state, name) => {
	if (!state.localModules) {
		state.localModules = [];
	}
	const m = new LocalModule(name, state.localModules.length);
	state.localModules.push(m);
	return m;
};

/**
 * Returns local module or null.
 * @param {JavascriptParserState} state parser state
 * @param {string} name name
 * @param {string=} namedModule named module
 * @returns {LocalModule | null} local module or null
 */
module.exports.getLocalModule = (state, name, namedModule) => {
	if (!state.localModules) return null;
	if (namedModule) {
		// resolve dependency name relative to the defining named module
		name = lookup(namedModule, name);
	}
	for (let i = 0; i < state.localModules.length; i++) {
		if (state.localModules[i].name === name) {
			return state.localModules[i];
		}
	}
	return null;
};