fix(webpack): add standardWebpackConfigFunction option when users opts for a standard config function (#20702)

docs/generated/packages/webpack/executors/webpack.json

@@ -313,6 +313,11 @@
         "default": true,
         "x-deprecated": "Automatic configuration of Webpack is deprecated in favor of an explicit 'webpack.config.js' file. This option will be removed in Nx 18. See https://nx.dev/recipes/webpack/webpack-config-setup."
       },
+      "standardWebpackConfigFunction": {
+        "type": "boolean",
+        "description": "Set to true if the webpack config exports a standard webpack function, not an Nx-specific one. See: https://webpack.js.org/configuration/configuration-types/#exporting-a-function",
+        "default": false
+      },
       "extractLicenses": {
         "type": "boolean",
         "description": "Extract all licenses in a separate file, in the case of production builds only."

packages/webpack/src/executors/dev-server/dev-server.impl.ts

@@ -81,7 +81,11 @@ export async function* devServerExecutor(
 
     // Only add the dev server option if user is composable plugin.
     // Otherwise, user should define `devServer` option directly in their webpack config.
-    if (isNxWebpackComposablePlugin(userDefinedWebpackConfig)) {
+    if (
+      typeof userDefinedWebpackConfig === 'function' &&
+      isNxWebpackComposablePlugin(userDefinedWebpackConfig) &&
+      !buildOptions.standardWebpackConfigFunction
+    ) {
       config = await userDefinedWebpackConfig(
         { devServer },
         {

packages/webpack/src/executors/webpack/schema.d.ts

@@ -50,6 +50,7 @@ export interface WebpackExecutorOptions {
   // TODO(v18): Remove this option
   /** @deprecated set webpackConfig and provide an explicit webpack.config.js file (See: https://nx.dev/recipes/webpack/webpack-config-setup) */
   isolatedConfig?: boolean;
+  standardWebpackConfigFunction?: boolean;
   main?: string;
   memoryLimit?: number;
   namedChunks?: boolean;

packages/webpack/src/executors/webpack/schema.json

@@ -237,6 +237,11 @@
       "default": true,
       "x-deprecated": "Automatic configuration of Webpack is deprecated in favor of an explicit 'webpack.config.js' file. This option will be removed in Nx 18. See https://nx.dev/recipes/webpack/webpack-config-setup."
     },
+    "standardWebpackConfigFunction": {
+      "type": "boolean",
+      "description": "Set to true if the webpack config exports a standard webpack function, not an Nx-specific one. See: https://webpack.js.org/configuration/configuration-types/#exporting-a-function",
+      "default": false
+    },
     "extractLicenses": {
       "type": "boolean",
       "description": "Extract all licenses in a separate file, in the case of production builds only."

packages/webpack/src/executors/webpack/webpack.impl.ts

@@ -58,7 +58,11 @@ async function getWebpackConfigs(
         ? composePluginsSync(withNx(options), withWeb(options))
         : withNx(options))({}, { options, context });
 
-  if (isNxWebpackComposablePlugin(userDefinedWebpackConfig)) {
+  if (
+    typeof userDefinedWebpackConfig === 'function' &&
+    isNxWebpackComposablePlugin(userDefinedWebpackConfig) &&
+    !options.standardWebpackConfigFunction
+  ) {
     // Old behavior, call the Nx-specific webpack config function that user exports
     return await userDefinedWebpackConfig(config, {
       options,