WIP - add extractor, generate snippet_data

node_modules/enhanced-resolve/lib/AliasFieldPlugin.js

@@ -0,0 +1,52 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+"use strict";
+
+const DescriptionFileUtils = require("./DescriptionFileUtils");
+const getInnerRequest = require("./getInnerRequest");
+
+module.exports = class AliasFieldPlugin {
+	constructor(source, field, target) {
+		this.source = source;
+		this.field = field;
+		this.target = target;
+	}
+
+	apply(resolver) {
+		const target = resolver.ensureHook(this.target);
+		resolver.getHook(this.source).tapAsync("AliasFieldPlugin", (request, resolveContext, callback) => {
+			if(!request.descriptionFileData) return callback();
+			const innerRequest = getInnerRequest(resolver, request);
+			if(!innerRequest) return callback();
+			const fieldData = DescriptionFileUtils.getField(request.descriptionFileData, this.field);
+			if(typeof fieldData !== "object") {
+				if(resolveContext.log) resolveContext.log("Field '" + this.field + "' doesn't contain a valid alias configuration");
+				return callback();
+			}
+			const data1 = fieldData[innerRequest];
+			const data2 = fieldData[innerRequest.replace(/^\.\//, "")];
+			const data = typeof data1 !== "undefined" ? data1 : data2;
+			if(data === innerRequest) return callback();
+			if(data === undefined) return callback();
+			if(data === false) {
+				const ignoreObj = Object.assign({}, request, {
+					path: false
+				});
+				return callback(null, ignoreObj);
+			}
+			const obj = Object.assign({}, request, {
+				path: request.descriptionFileRoot,
+				request: data
+			});
+			resolver.doResolve(target, obj, "aliased from description file " + request.descriptionFilePath + " with mapping '" + innerRequest + "' to '" + data + "'", resolveContext, (err, result) => {
+				if(err) return callback(err);
+
+				// Don't allow other aliasing or raw request
+				if(result === undefined) return callback(null, null);
+				callback(null, result);
+			});
+		});
+	}
+};