webpack/lib/util/implicitTypeLoaderFallback.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 Alexander Akait @alexander-akait
*/

"use strict";

const { JAVASCRIPT_MODULE_TYPE_AUTO } = require("../ModuleTypeConstants");
const { parseResource } = require("./identifier");

/** @typedef {import("../NormalModuleFactory")} NormalModuleFactory */

/**
 * When a built-in module type is only enabled implicitly (`experiments.css` /
 * `experiments.html` resolved from their `"auto"` default), modules that reach
 * the factory with loaders applied — an inline request or loaders injected via
 * hooks (e.g. html-webpack-plugin's template loader) — keep the pre-existing
 * behavior: the loader result is parsed as JavaScript, not as the built-in type.
 * A `!=!` matchResource is an explicit re-type of the loader result and wins.
 *
 * TODO webpack 6: css/html are enabled unconditionally (`experiments.*: true`),
 * so this implicit-only workaround can be removed together with the `"auto"`
 * marker in `applyExperimentsDefaults`.
 * @param {NormalModuleFactory} normalModuleFactory the normal module factory
 * @param {string} pluginName name of the calling plugin, used for the tap
 * @param {RegExp} test resource path test of the built-in default rule
 * @param {string} type built-in module type assigned by that default rule
 * @returns {void}
 */
module.exports = (normalModuleFactory, pluginName, test, type) => {
	normalModuleFactory.hooks.createModule.tap(
		pluginName,
		(createData, _resolveData) => {
			if (
				createData.settings.type !== type ||
				createData.loaders.length === 0 ||
				createData.matchResource !== undefined ||
				!test.test(parseResource(createData.resource).path)
			) {
				return;
			}
			// Drop the default rule's type-specific effects along with the type
			createData.settings = {
				...createData.settings,
				type: JAVASCRIPT_MODULE_TYPE_AUTO,
				parser: undefined,
				generator: undefined,
				resolve: undefined
			};
			createData.type = JAVASCRIPT_MODULE_TYPE_AUTO;
			createData.parser = normalModuleFactory.getParser(
				JAVASCRIPT_MODULE_TYPE_AUTO
			);
			createData.parserOptions = undefined;
			createData.generator = normalModuleFactory.getGenerator(
				JAVASCRIPT_MODULE_TYPE_AUTO
			);
			createData.generatorOptions = undefined;
			createData.resolveOptions = undefined;
		}
	);
};