fix standalone wrong url being logged (#44887)

Co-authored-by: JJ Kasper <[email protected]>

Author: IgnisDa

packages/next/src/build/utils.ts

@@ -1789,7 +1789,7 @@ server.listen(currentPort, (err) => {
   console.log(
     'Listening on port',
     currentPort,
-    'url: http://localhost:' + currentPort
+    'url: http://' + hostname + ':' + currentPort
   )
 })`
   )

test/production/standalone-mode/response-cache/index.test.ts

@@ -15,6 +15,7 @@ describe('minimal-mode-response-cache', () => {
   let next: NextInstance
   let server
   let appPort
+  let output = ''
 
   beforeAll(async () => {
     // test build against environment with next support
@@ -59,11 +60,18 @@ describe('minimal-mode-response-cache', () => {
       /Listening on/,
       {
         ...process.env,
+        HOSTNAME: '',
         PORT: appPort,
       },
       undefined,
       {
         cwd: next.testDir,
+        onStdout(msg) {
+          output += msg
+        },
+        onStderr(msg) {
+          output += msg
+        },
       }
     )
   })
@@ -72,6 +80,11 @@ describe('minimal-mode-response-cache', () => {
     if (server) await killApp(server)
   })
 
+  it('should have correct "Listening on" log', async () => {
+    expect(output).toContain(`Listening on port`)
+    expect(output).toContain(`url: http://localhost:${appPort}`)
+  })
+
   it('should have correct responses', async () => {
     const html = await renderViaHTTP(appPort, '/')
     expect(html.length).toBeTruthy()