From d83ec5a0b5bafdff7807e2680baf9dd3fb8fcef7 Mon Sep 17 00:00:00 2001
From: "Michael \"Z\" Goddard" <mzgoddard@gmail.com>
Date: Tue, 30 Apr 2019 10:37:43 -0400
Subject: [PATCH] replace blocks timeout with a promise

The timeout as a promise lets us update the toolbox during the same
render as the workspace so that the screen updates all together. This
also means the toolbox will update before the loading screen is
dismissed after loading, letting us avoid a second flash for the
toolbox to update.
---
 src/containers/blocks.jsx | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/containers/blocks.jsx b/src/containers/blocks.jsx
index c366da458..694c50cbd 100644
--- a/src/containers/blocks.jsx
+++ b/src/containers/blocks.jsx
@@ -180,13 +180,19 @@ class Blocks extends React.Component {
     componentWillUnmount () {
         this.detachVM();
         this.workspace.dispose();
-        clearTimeout(this.toolboxUpdateTimeout);
+        if (this.toolboxUpdateTimeout) this.toolboxUpdateTimeout.cancel();
     }
     requestToolboxUpdate () {
-        clearTimeout(this.toolboxUpdateTimeout);
-        this.toolboxUpdateTimeout = setTimeout(() => {
-            this.updateToolbox();
-        }, 0);
+        if (this.toolboxUpdateTimeout) this.toolboxUpdateTimeout.cancel();
+        let running = true;
+        this.toolboxUpdateTimeout = Promise.resolve().then(() => {
+            if (running) {
+                this.updateToolbox();
+            }
+        });
+        this.toolboxUpdateTimeout.cancel = () => {
+            running = false;
+        };
     }
     setLocale () {
         this.ScratchBlocks.ScratchMsgs.setLocale(this.props.locale);