From dd3d3f84f83ef304b0f47c4e041f10101b463283 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <bvaughn@fb.com>
Date: Thu, 20 Jan 2022 10:15:30 -0500
Subject: [PATCH] Don't inject timeline hooks unless React supports profiling
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This gives DevTools a way to detect whether the current React renderer supports Timeline profiling. (Version alone isn't enough to detect this, neither is general profiling support– since these two are controlled by different feature flags.)
---
 .../src/ReactFiberDevToolsHook.new.js          | 18 +++++++++++++-----
 .../src/ReactFiberDevToolsHook.old.js          | 18 +++++++++++++-----
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js b/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
index 2978f7b3279b5..6a523d2627f80 100644
--- a/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
+++ b/packages/react-reconciler/src/ReactFiberDevToolsHook.new.js
@@ -74,11 +74,19 @@ export function injectInternals(internals: Object): boolean {
     return true;
   }
   try {
-    rendererID = hook.inject({
-      ...internals,
-      getLaneLabelMap,
-      injectProfilingHooks,
-    });
+    if (enableSchedulingProfiler) {
+      // Conditionally inject these hooks only if Timeline profiler is supported by this build.
+      // This gives DevTools a way to feature detect that isn't tied to version number
+      // (since profiling and timeline are controlled by different feature flags).
+      internals = {
+        ...internals,
+        getLaneLabelMap,
+        injectProfilingHooks,
+      };
+    }
+
+    rendererID = hook.inject(internals);
+
     // We have successfully injected, so now it is safe to set up hooks.
     injectedHook = hook;
   } catch (err) {
diff --git a/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js b/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
index d26d12236c24c..6fae56afcb251 100644
--- a/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
+++ b/packages/react-reconciler/src/ReactFiberDevToolsHook.old.js
@@ -74,11 +74,19 @@ export function injectInternals(internals: Object): boolean {
     return true;
   }
   try {
-    rendererID = hook.inject({
-      ...internals,
-      getLaneLabelMap,
-      injectProfilingHooks,
-    });
+    if (enableSchedulingProfiler) {
+      // Conditionally inject these hooks only if Timeline profiler is supported by this build.
+      // This gives DevTools a way to feature detect that isn't tied to version number
+      // (since profiling and timeline are controlled by different feature flags).
+      internals = {
+        ...internals,
+        getLaneLabelMap,
+        injectProfilingHooks,
+      };
+    }
+
+    rendererID = hook.inject(internals);
+
     // We have successfully injected, so now it is safe to set up hooks.
     injectedHook = hook;
   } catch (err) {