fix: support babel-7 and babel-loader-8

Author: hubcarl

lib/base.js

@@ -593,7 +593,7 @@ class WebpackBaseBuilder extends Config {
 
   createBabelLoader() {
     const loaderName = 'babel-loader';
-    const options = { forceEnv: process.env.BABEL_ENV };
+    const options = process.env.BABEL_ENV ? { forceEnv: process.env.BABEL_ENV } : {};
     const compile = this.config.compile || {};
     const configCacheOptions = this.utils.isObject(compile.cache) ? compile.cache : {};
     const cacheOptions = this.merge(options, configCacheOptions);

package.json

@@ -1,6 +1,6 @@
 {
   "name": "easywebpack",
-  "version": "4.9.2",
+  "version": "4.9.3",
   "description": "基于 Webpack 的前端构建工程化解决方案",
   "keywords": [
     "webpack",