From 57cd762262c2f8f70a9511304a074ae92d8fa986 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Tue, 21 Sep 2021 18:24:16 +0300
Subject: [PATCH] Get key from item (not props), do not update state if there
 is no change

---
 virtualRender.js | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/virtualRender.js b/virtualRender.js
index d410b48..0d35a4f 100644
--- a/virtualRender.js
+++ b/virtualRender.js
@@ -2,7 +2,7 @@
 // Simpler alternative to react-test-renderer, also allows to visit element tree during rendering
 //
 // (c) Vitaliy Filippov 2021+
-// Version: 2021-09-20
+// Version: 2021-09-21
 // License: Dual-license MPL 1.1+ or GNU LGPL 3.0+
 // Credits to react-apollo/getDataFromTree.ts and react-tree-walker
 
@@ -92,7 +92,7 @@ function walkTree(tree, visitor, context, options, path = '')
         for (let item of tree)
         {
             let type = item && getType(item);
-            let key = item && getProps(item)?.key;
+            let key = item && item.key;
             if (lastType == type && lastHasKey == (key != null))
                 index++;
             else
@@ -197,8 +197,15 @@ function walkTree(tree, visitor, context, options, path = '')
                             // eslint-disable-next-line no-param-reassign
                             newState = newState(instance.state, instance.props, instance.context);
                         }
-                        instance.state = { ...instance.state, ...newState };
-                        options.shouldUpdate = true;
+                        for (let k in newState)
+                        {
+                            if (instance.state[k] !== newState[k])
+                            {
+                                instance.state = { ...instance.state, ...newState };
+                                options.shouldUpdate = true;
+                                break;
+                            }
+                        }
                         if (callback)
                         {
                             callback();