From 2cb8ba6521f59444680b879e3b343c5bc859df76 Mon Sep 17 00:00:00 2001
From: Warren Seine <w.seine@criteo.com>
Date: Thu, 13 Aug 2020 17:20:38 +0200
Subject: [PATCH] add explanation for why we mutate collaborators state (#2028)
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* 🔒 Avoid mutating state

* revert to mutation and add explaining comment

Co-authored-by: dwelle <luzar.david@gmail.com>
---
 src/components/App.tsx | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/components/App.tsx b/src/components/App.tsx
index 3644ffee..ec08b467 100644
--- a/src/components/App.tsx
+++ b/src/components/App.tsx
@@ -1299,6 +1299,8 @@ class App extends React.Component<ExcalidrawProps, AppState> {
                 username,
                 selectedElementIds,
               } = decryptedData.payload;
+              // NOTE purposefully mutating collaborators map in case of
+              //  pointer updates so as not to trigger LayerUI rerender
               this.setState((state) => {
                 if (!state.collaborators.has(socketID)) {
                   state.collaborators.set(socketID, {});