From 1072303e20ddf2f2830f5d60c116b35f60640e37 Mon Sep 17 00:00:00 2001
From: Anton Korzunov <thekashey@gmail.com>
Date: Sat, 2 Nov 2019 18:09:41 +1100
Subject: [PATCH] fix: dont write to elementType if it is not defined, fixes
 #1357

---
 src/internal/getReactStack.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/internal/getReactStack.js b/src/internal/getReactStack.js
index d0736b123..71819a7ab 100644
--- a/src/internal/getReactStack.js
+++ b/src/internal/getReactStack.js
@@ -42,7 +42,10 @@ const markUpdate = ({ fiber }) => {
   if (fiber.alternate) {
     fiber.alternate.expirationTime = 1;
     fiber.alternate.type = fiber.type;
-    fiber.alternate.elementType = fiber.elementType;
+    // elementType might not exists in older react versions
+    if ('elementType' in fiber.alternate) {
+      fiber.alternate.elementType = fiber.elementType;
+    }
   }
 
   if (fiber.memoizedProps && typeof fiber.memoizedProps === 'object') {