From c55c34e46a6d8148afb78594d14f4675f9346900 Mon Sep 17 00:00:00 2001
From: Dominic Gannaway <trueadm@users.noreply.github.com>
Date: Fri, 7 Feb 2020 12:21:50 +0000
Subject: [PATCH] Move React Map child check to behind flags or __DEV__
 (#17995)

---
 packages/react/src/ReactChildren.js | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/packages/react/src/ReactChildren.js b/packages/react/src/ReactChildren.js
index 9329d89c57c16..6e65fd8ddcde9 100644
--- a/packages/react/src/ReactChildren.js
+++ b/packages/react/src/ReactChildren.js
@@ -159,17 +159,18 @@ function traverseAllChildrenImpl(
   } else {
     const iteratorFn = getIteratorFn(children);
     if (typeof iteratorFn === 'function') {
-      if (iteratorFn === children.entries) {
-        if (disableMapsAsChildren) {
-          invariant(
-            false,
-            'Maps are not valid as a React child (found: %s). Consider converting ' +
-              'children to an array of keyed ReactElements instead.',
-            children,
-          );
-        }
+      if (disableMapsAsChildren) {
+        invariant(
+          iteratorFn !== children.entries,
+          'Maps are not valid as a React child (found: %s). Consider converting ' +
+            'children to an array of keyed ReactElements instead.',
+          children,
+        );
+      }
+
+      if (__DEV__) {
         // Warn about using Maps as children
-        if (__DEV__) {
+        if (iteratorFn === children.entries) {
           if (!didWarnAboutMaps) {
             console.warn(
               'Using Maps as children is deprecated and will be removed in ' +