update

node_modules/enhanced-resolve/lib/MainFieldPlugin.js

@@ -0,0 +1,66 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+"use strict";
+
+const path = require("path");
+
+module.exports = class MainFieldPlugin {
+	constructor(source, options, target) {
+		this.source = source;
+		this.options = options;
+		this.target = target;
+	}
+
+	apply(resolver) {
+		const target = resolver.ensureHook(this.target);
+		resolver
+			.getHook(this.source)
+			.tapAsync("MainFieldPlugin", (request, resolveContext, callback) => {
+				if (request.path !== request.descriptionFileRoot) return callback();
+				if (request.alreadyTriedMainField === request.descriptionFilePath)
+					return callback();
+				const content = request.descriptionFileData;
+				const filename = path.basename(request.descriptionFilePath);
+				let mainModule;
+				const field = this.options.name;
+				if (Array.isArray(field)) {
+					let current = content;
+					for (let j = 0; j < field.length; j++) {
+						if (current === null || typeof current !== "object") {
+							current = null;
+							break;
+						}
+						current = current[field[j]];
+					}
+					if (typeof current === "string") {
+						mainModule = current;
+					}
+				} else {
+					if (typeof content[field] === "string") {
+						mainModule = content[field];
+					}
+				}
+				if (!mainModule) return callback();
+				if (this.options.forceRelative && !/^\.\.?\//.test(mainModule))
+					mainModule = "./" + mainModule;
+				const obj = Object.assign({}, request, {
+					request: mainModule,
+					alreadyTriedMainField: request.descriptionFilePath
+				});
+				return resolver.doResolve(
+					target,
+					obj,
+					"use " +
+						mainModule +
+						" from " +
+						this.options.name +
+						" in " +
+						filename,
+					resolveContext,
+					callback
+				);
+			});
+	}
+};