test: do not wait for unstable_after callbacks in dev

test/e2e/app-dir/graceful-shutdown-next-after/index.test.ts

@@ -0,0 +1,45 @@
+import { nextTestSetup } from 'e2e-utils'
+import { retry } from 'next-test-utils'
+
+describe('unstable_after during server shutdown', () => {
+  const { next, skipped, isNextDev } = nextTestSetup({
+    files: __dirname,
+    skipDeployment: true, // the tests use cli logs
+    skipStart: true,
+  })
+  if (skipped) {
+    return
+  }
+
+  beforeEach(async () => {
+    await next.start()
+  })
+
+  if (isNextDev) {
+    it.each(['SIGINT', 'SIGTERM'] as const)(
+      'does not wait for unstable_after callbacks when the server receives %s',
+      async (signal) => {
+        await next.browser('/')
+        await retry(async () => {
+          expect(next.cliOutput).toInclude('[after] starting sleep')
+        })
+        await next.stop(signal)
+        expect(next.cliOutput).not.toInclude('[after] finished sleep')
+      }
+    )
+  }
+
+  if (!isNextDev) {
+    it.each(['SIGINT', 'SIGTERM'] as const)(
+      'waits for unstable_after callbacks when the server receives %s',
+      async (signal) => {
+        await next.browser('/')
+        await retry(async () => {
+          expect(next.cliOutput).toInclude('[after] starting sleep')
+        })
+        await next.stop(signal)
+        expect(next.cliOutput).toInclude('[after] finished sleep')
+      }
+    )
+  }
+})