Enable production sourcemap for index.js, fix css sourcemaps

Author: silverwind

docs/content/installation/from-source.en-us.md

@@ -128,7 +128,7 @@ If pre-built frontend files are present it is possible to only build the backend
 TAGS="bindata" make backend
 ```
 
-Webpack source maps are by default enabled in development builds and disabled in production builds. They can be enabled by setting the `ENABLE_SOURCEMAP=true` environment variable.
+Webpack source maps are limited by default to conserve space. When `ENABLE_SOURCEMAP=true` is set, the webpack build will generate all source maps.
 
 ## Test
 

docs/content/installation/from-source.zh-cn.md

@@ -100,7 +100,7 @@ TAGS="bindata sqlite sqlite_unlock_notify" make build
 TAGS="bindata" make backend
 ```
 
-在开发构建中，默认启用 Webpack 源映射，在生产构建中禁用。可以通过设置`ENABLE_SOURCEMAP=true`环境变量来启用它们。
+默认情况下，Webpack 源映射受到限制以节省空间。 当设置`ENABLE_SOURCEMAP=true`时，webpack 构建将生成所有源映射。
 
 ## 测试
 

webpack.config.js

@@ -28,11 +28,13 @@ for (const path of glob('web_src/css/themes/*.css')) {
 
 const isProduction = env.NODE_ENV !== 'development';
 
-let sourceMapEnabled;
+// The production build only generates limited sourcemaps to conserve binary size.
+// When in development or when ENABLE_SOURCEMAP=true, generate all source maps.
+let fullSourceMapEnabled;
 if ('ENABLE_SOURCEMAP' in env) {
-  sourceMapEnabled = env.ENABLE_SOURCEMAP === 'true';
+  fullSourceMapEnabled = env.ENABLE_SOURCEMAP === 'true';
 } else {
-  sourceMapEnabled = !isProduction;
+  fullSourceMapEnabled = !isProduction;
 }
 
 const filterCssImport = (url, ...args) => {
@@ -105,7 +107,9 @@ export default {
         css: !LightningCssMinifyPlugin,
         legalComments: 'none',
       }),
-      LightningCssMinifyPlugin && new LightningCssMinifyPlugin(),
+      LightningCssMinifyPlugin && new LightningCssMinifyPlugin({
+        sourceMap: fullSourceMapEnabled,
+      }),
     ],
     splitChunks: {
       chunks: 'async',
@@ -143,7 +147,7 @@ export default {
           {
             loader: 'css-loader',
             options: {
-              sourceMap: sourceMapEnabled,
+              sourceMap: fullSourceMapEnabled,
               url: {filter: filterCssImport},
               import: {filter: filterCssImport},
             },
@@ -181,9 +185,10 @@ export default {
       filename: 'css/[name].css',
       chunkFilename: 'css/[name].[contenthash:8].css',
     }),
-    sourceMapEnabled && (new SourceMapDevToolPlugin({
+    new SourceMapDevToolPlugin({
       filename: '[file].[contenthash:8].map',
-    })),
+      ...(!fullSourceMapEnabled && {include: /^js\/index\.js$/}),
+    }),
     new MonacoWebpackPlugin({
       filename: 'js/monaco-[name].[contenthash:8].worker.js',
     }),