From 71ae3e68c65b8a9b8c6d79632af5ba744bab7073 Mon Sep 17 00:00:00 2001
From: Dan Abramov <dan.abramov@me.com>
Date: Tue, 13 Jul 2021 15:13:19 +0100
Subject: [PATCH] Restore DevTools console message

---
 .../react-reconciler/src/ReactFiberDevToolsHook.new.js   | 9 +++++++--
 .../react-reconciler/src/ReactFiberDevToolsHook.old.js   | 9 +++++++--
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js b/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
index e7bde59e20cba..52d1c68730c61 100644
--- a/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
+++ b/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
@@ -69,8 +69,13 @@ export function injectInternals(internals: Object): boolean {
       console.error('React instrumentation encountered an error: %s.', err);
     }
   }
-  // DevTools exists
-  return true;
+  if (hook.checkDCE) {
+    // This is the real DevTools.
+    return true;
+  } else {
+    // This is likely a hook installed by Fast Refresh runtime.
+    return false;
+  }
 }
 
 export function onScheduleRoot(root: FiberRoot, children: ReactNodeList) {
diff --git a/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js b/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
index 494138685e104..42fd68a93a8bc 100644
--- a/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
+++ b/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
@@ -69,8 +69,13 @@ export function injectInternals(internals: Object): boolean {
       console.error('React instrumentation encountered an error: %s.', err);
     }
   }
-  // DevTools exists
-  return true;
+  if (hook.checkDCE) {
+    // This is the real DevTools.
+    return true;
+  } else {
+    // This is likely a hook installed by Fast Refresh runtime.
+    return false;
+  }
 }
 
 export function onScheduleRoot(root: FiberRoot, children: ReactNodeList) {