1 files changed, 154 insertions, 0 deletions
diff --git a/node_modules/enhanced-resolve/lib/AliasPlugin.js b/node_modules/enhanced-resolve/lib/AliasPlugin.js
new file mode 100644
index 00000000..bbe9724a
--- /dev/null
+++ b/node_modules/enhanced-resolve/lib/AliasPlugin.js
@@ -0,0 +1,154 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+
+"use strict";
+
+const forEachBail = require("./forEachBail");
+const { PathType, getType } = require("./util/path");
+
+/** @typedef {import("./Resolver")} Resolver */
+/** @typedef {import("./Resolver").ResolveRequest} ResolveRequest */
+/** @typedef {import("./Resolver").ResolveStepHook} ResolveStepHook */
+/** @typedef {string | Array<string> | false} Alias */
+/** @typedef {{alias: Alias, name: string, onlyModule?: boolean}} AliasOption */
+
+module.exports = class AliasPlugin {
+	/**
+	 * @param {string | ResolveStepHook} source source
+	 * @param {AliasOption | Array<AliasOption>} options options
+	 * @param {string | ResolveStepHook} target target
+	 */
+	constructor(source, options, target) {
+		this.source = source;
+		this.options = Array.isArray(options) ? options : [options];
+		this.target = target;
+	}
+
+	/**
+	 * @param {Resolver} resolver the resolver
+	 * @returns {void}
+	 */
+	apply(resolver) {
+		const target = resolver.ensureHook(this.target);
+		/**
+		 * @param {string} maybeAbsolutePath path
+		 * @returns {null|string} absolute path with slash ending
+		 */
+		const getAbsolutePathWithSlashEnding = maybeAbsolutePath => {
+			const type = getType(maybeAbsolutePath);
+			if (type === PathType.AbsolutePosix || type === PathType.AbsoluteWin) {
+				return resolver.join(maybeAbsolutePath, "_").slice(0, -1);
+			}
+			return null;
+		};
+		/**
+		 * @param {string} path path
+		 * @param {string} maybeSubPath sub path
+		 * @returns {boolean} true, if path is sub path
+		 */
+		const isSubPath = (path, maybeSubPath) => {
+			const absolutePath = getAbsolutePathWithSlashEnding(maybeSubPath);
+			if (!absolutePath) return false;
+			return path.startsWith(absolutePath);
+		};
+		resolver
+			.getHook(this.source)
+			.tapAsync("AliasPlugin", (request, resolveContext, callback) => {
+				const innerRequest = request.request || request.path;
+				if (!innerRequest) return callback();
+				forEachBail(
+					this.options,
+					(item, callback) => {
+						/** @type {boolean} */
+						let shouldStop = false;
+						if (
+							innerRequest === item.name ||
+							(!item.onlyModule &&
+								(request.request
+									? innerRequest.startsWith(`${item.name}/`)
+									: isSubPath(innerRequest, item.name)))
+						) {
+							/** @type {string} */
+							const remainingRequest = innerRequest.slice(item.name.length);
+							/**
+							 * @param {Alias} alias alias
+							 * @param {(err?: null|Error, result?: null|ResolveRequest) => void} callback callback
+							 * @returns {void}
+							 */
+							const resolveWithAlias = (alias, callback) => {
+								if (alias === false) {
+									/** @type {ResolveRequest} */
+									const ignoreObj = {
+										...request,
+										path: false
+									};
+									if (typeof resolveContext.yield === "function") {
+										resolveContext.yield(ignoreObj);
+										return callback(null, null);
+									}
+									return callback(null, ignoreObj);
+								}
+								if (
+									innerRequest !== alias &&
+									!innerRequest.startsWith(alias + "/")
+								) {
+									shouldStop = true;
+									const newRequestStr = alias + remainingRequest;
+									/** @type {ResolveRequest} */
+									const obj = {
+										...request,
+										request: newRequestStr,
+										fullySpecified: false
+									};
+									return resolver.doResolve(
+										target,
+										obj,
+										"aliased with mapping '" +
+											item.name +
+											"': '" +
+											alias +
+											"' to '" +
+											newRequestStr +
+											"'",
+										resolveContext,
+										(err, result) => {
+											if (err) return callback(err);
+											if (result) return callback(null, result);
+											return callback();
+										}
+									);
+								}
+								return callback();
+							};
+							/**
+							 * @param {null|Error} [err] error
+							 * @param {null|ResolveRequest} [result] result
+							 * @returns {void}
+							 */
+							const stoppingCallback = (err, result) => {
+								if (err) return callback(err);
+
+								if (result) return callback(null, result);
+								// Don't allow other aliasing or raw request
+								if (shouldStop) return callback(null, null);
+								return callback();
+							};
+							if (Array.isArray(item.alias)) {
+								return forEachBail(
+									item.alias,
+									resolveWithAlias,
+									stoppingCallback
+								);
+							} else {
+								return resolveWithAlias(item.alias, stoppingCallback);
+							}
+						}
+						return callback();
+					},
+					callback
+				);
+			});
+	}
+};