From c37ba815846e1f4fd7643632b6d40de2c37c7199 Mon Sep 17 00:00:00 2001 From: Jan Karres Date: Tue, 1 Oct 2019 21:10:11 +0200 Subject: [PATCH] Check if 'formatAmpMessages' returns a none empty string in Next.js build process --- packages/next/build/output/index.ts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/packages/next/build/output/index.ts b/packages/next/build/output/index.ts index c4c9cf0a074c3..d25109aaa0e6e 100644 --- a/packages/next/build/output/index.ts +++ b/packages/next/build/output/index.ts @@ -173,7 +173,7 @@ buildStore.subscribe(state => { } if (Object.keys(amp).length > 0) { - warnings = (warnings || []).concat(formatAmpMessages(amp)) + warnings = (warnings || []).concat(formatAmpMessages(amp) || []) if (!warnings.length) warnings = null } }