Disable Comment Extraction (#12496)

packages/next/build/webpack-config.ts

@@ -640,6 +640,7 @@ export default async function getBaseWebpackConfig(
       minimizer: [
         // Minify JavaScript
         new TerserPlugin({
+          extractComments: false,
           cache: path.join(distDir, 'cache', 'next-minifier'),
           parallel: config.experimental.cpus || true,
           terserOptions,

test/integration/build-output/fixtures/basic-app/pages/index.js

@@ -1,3 +1,4 @@
+/*! DO NOT EXTRACT ME */
 export default function() {
   return <div />
 }

test/integration/build-output/test/index.test.js

@@ -4,6 +4,7 @@ import 'flat-map-polyfill'
 import { remove } from 'fs-extra'
 import { nextBuild } from 'next-test-utils'
 import { join } from 'path'
+import { recursiveReadDir } from 'next/dist/lib/recursive-readdir'
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 1000 * 60 * 2
 
@@ -34,6 +35,14 @@ describe('Build Output', () => {
 
       expect(stdout).toContain('○ /')
     })
+
+    it('should not emit extracted comments', async () => {
+      const files = await recursiveReadDir(
+        join(appDir, '.next'),
+        /\.txt|\.LICENSE\./
+      )
+      expect(files).toEqual([])
+    })
   })
 
   describe('Custom App Output', () => {