From 9fae92f3da04a93b4414c570aa2b65c81664b04d Mon Sep 17 00:00:00 2001
From: Haz <hazdiego@gmail.com>
Date: Sat, 20 Jun 2020 13:22:19 -0300
Subject: [PATCH] Memoize useSelect callbacks on the header toolbar items
 (#23337)

---
 packages/editor/src/components/editor-history/redo.js     | 5 +++--
 packages/editor/src/components/editor-history/undo.js     | 5 +++--
 packages/editor/src/components/table-of-contents/index.js | 3 ++-
 packages/editor/src/components/table-of-contents/panel.js | 3 ++-
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/packages/editor/src/components/editor-history/redo.js b/packages/editor/src/components/editor-history/redo.js
index 7bfd25a81ba715..59487eaeb5a2ab 100644
--- a/packages/editor/src/components/editor-history/redo.js
+++ b/packages/editor/src/components/editor-history/redo.js
@@ -9,8 +9,9 @@ import { redo as redoIcon } from '@wordpress/icons';
 import { forwardRef } from '@wordpress/element';
 
 function EditorHistoryRedo( props, ref ) {
-	const hasRedo = useSelect( ( select ) =>
-		select( 'core/editor' ).hasEditorRedo()
+	const hasRedo = useSelect(
+		( select ) => select( 'core/editor' ).hasEditorRedo(),
+		[]
 	);
 	const { redo } = useDispatch( 'core/editor' );
 	return (
diff --git a/packages/editor/src/components/editor-history/undo.js b/packages/editor/src/components/editor-history/undo.js
index bb6d3907e85b16..67bd3d58f4f499 100644
--- a/packages/editor/src/components/editor-history/undo.js
+++ b/packages/editor/src/components/editor-history/undo.js
@@ -9,8 +9,9 @@ import { undo as undoIcon } from '@wordpress/icons';
 import { forwardRef } from '@wordpress/element';
 
 function EditorHistoryUndo( props, ref ) {
-	const hasUndo = useSelect( ( select ) =>
-		select( 'core/editor' ).hasEditorUndo()
+	const hasUndo = useSelect(
+		( select ) => select( 'core/editor' ).hasEditorUndo(),
+		[]
 	);
 	const { undo } = useDispatch( 'core/editor' );
 	return (
diff --git a/packages/editor/src/components/table-of-contents/index.js b/packages/editor/src/components/table-of-contents/index.js
index 9d3d3e959b326c..f7cfb0cfc242ea 100644
--- a/packages/editor/src/components/table-of-contents/index.js
+++ b/packages/editor/src/components/table-of-contents/index.js
@@ -14,7 +14,8 @@ import TableOfContentsPanel from './panel';
 
 function TableOfContents( { hasOutlineItemsDisabled, ...props }, ref ) {
 	const hasBlocks = useSelect(
-		( select ) => !! select( 'core/block-editor' ).getBlockCount()
+		( select ) => !! select( 'core/block-editor' ).getBlockCount(),
+		[]
 	);
 	return (
 		<Dropdown
diff --git a/packages/editor/src/components/table-of-contents/panel.js b/packages/editor/src/components/table-of-contents/panel.js
index f9a40ddceefa27..01e59eab13ed41 100644
--- a/packages/editor/src/components/table-of-contents/panel.js
+++ b/packages/editor/src/components/table-of-contents/panel.js
@@ -19,7 +19,8 @@ function TableOfContentsPanel( { hasOutlineItemsDisabled, onRequestClose } ) {
 				paragraphCount: getGlobalBlockCount( 'core/paragraph' ),
 				numberOfBlocks: getGlobalBlockCount(),
 			};
-		}
+		},
+		[]
 	);
 	return (
 		/*