From 153cc7d0591032ebd6c4b4df14b6a95a3799920b Mon Sep 17 00:00:00 2001
From: Andy Hanson <anhans@microsoft.com>
Date: Mon, 11 Dec 2017 06:50:55 -0800
Subject: [PATCH] Fix return type

---
 src/compiler/core.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/core.ts b/src/compiler/core.ts
index 188cd250605..5fcf69ed514 100644
--- a/src/compiler/core.ts
+++ b/src/compiler/core.ts
@@ -3262,7 +3262,7 @@ namespace ts {
         }
     }
 
-    export function singleElementArray<T>(t: T | undefined): T[] {
+    export function singleElementArray<T>(t: T | undefined): T[] | undefined {
         return t === undefined ? undefined : [t];
     }
 }