fix(nextjs): Running nx build --configuration=development should not …

…throw an error (#17866)

(cherry picked from commit 3008be1)

e2e/next/src/next.test.ts

@@ -1,6 +1,7 @@
 import { detectPackageManager, joinPathFragments } from '@nx/devkit';
 import { capitalize } from '@nx/devkit/src/utils/string-utils';
 import {
+  checkFilesDoNotExist,
   checkFilesExist,
   cleanupProject,
   getPackageManagerCommand,
@@ -355,6 +356,21 @@ describe('Next.js Applications', () => {
     checkFilesExist(`dist/apps/${appName}/next.config.js`);
   }, 300_000);
 
+  it('should build in dev mode without errors', async () => {
+    const appName = uniq('app');
+
+    runCLI(
+      `generate @nx/next:app ${appName} --no-interactive --style=css --appDir=false`
+    );
+
+    checkFilesDoNotExist(`apps/${appName}/.next/build-manifest.json`);
+    checkFilesDoNotExist(`apps/${appName}/.nx-helpers/with-nx.js`);
+
+    expect(() => {
+      runCLI(`build ${appName} --configuration=development`);
+    }).not.toThrow();
+  }, 300_000);
+
   it('should support --js flag', async () => {
     const appName = uniq('app');
 

packages/next/src/executors/build/build.impl.ts

@@ -92,11 +92,13 @@ export default async function buildExecutor(
     });
   }
 
-  createNextConfigFile(options, context);
-
-  copySync(join(projectRoot, 'public'), join(options.outputPath, 'public'), {
-    dereference: true,
-  });
-
+  // If output path is different from source path, then copy over the config and public files.
+  // This is the default behavior when running `nx build <app>`.
+  if (options.outputPath.replace(/\/$/, '') !== projectRoot) {
+    createNextConfigFile(options, context);
+    copySync(join(projectRoot, 'public'), join(options.outputPath, 'public'), {
+      dereference: true,
+    });
+  }
   return { success: true };
 }

packages/next/src/executors/build/lib/create-next-config-file.ts

@@ -24,6 +24,13 @@ export function createNextConfigFile(
   options: NextBuildBuilderOptions,
   context: ExecutorContext
 ) {
+  // Don't overwrite the next.config.js file if output path is the same as the source path.
+  if (
+    options.outputPath.replace(/\/$/, '') ===
+    context.projectGraph.nodes[context.projectName].data.root
+  ) {
+    return;
+  }
   const projectRoot = context.projectGraph.nodes[context.projectName].data.root;
   const configRelativeToProjectRoot = findNextConfigPath(
     projectRoot,