From 4015ae5c99519a5392db27f23223204c5b050f9c Mon Sep 17 00:00:00 2001
From: Sam Zhou <samzhou19815@meta.com>
Date: Fri, 12 Jun 2026 10:32:26 -0700
Subject: [PATCH] Eliminate legacy flow syntax in ReactNativeFeatureFlags.js

Summary: Changelog: [Internal]

Differential Revision: D108435552
---
 .flowconfig                                                 | 1 -
 .../templates/js/ReactNativeFeatureFlags.js-template.js     | 4 ++--
 .../src/private/featureflags/ReactNativeFeatureFlags.js     | 6 +++---
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/.flowconfig b/.flowconfig
index 540baf65ae44..aa3784a1c9e2 100644
--- a/.flowconfig
+++ b/.flowconfig
@@ -67,7 +67,6 @@ react.runtime=automatic
 
 experimental.deprecated_utilities.excludes=<PROJECT_ROOT>/packages/react-native/Libraries/Renderer/shims/ReactNativeTypes.js
 experimental.deprecated_utilities.excludes=<PROJECT_ROOT>/packages/react-native/Libraries/Renderer/shims/ReactNativeViewConfigRegistry.js
-experimental.deprecated_utilities.excludes=<PROJECT_ROOT>/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
 ban_spread_key_props=true
 
 [lints]
diff --git a/packages/react-native/scripts/featureflags/templates/js/ReactNativeFeatureFlags.js-template.js b/packages/react-native/scripts/featureflags/templates/js/ReactNativeFeatureFlags.js-template.js
index a31f082caa0a..e145f9f601ee 100644
--- a/packages/react-native/scripts/featureflags/templates/js/ReactNativeFeatureFlags.js-template.js
+++ b/packages/react-native/scripts/featureflags/templates/js/ReactNativeFeatureFlags.js-template.js
@@ -35,7 +35,7 @@ import {
   setOverrides,
 } from './ReactNativeFeatureFlagsBase';
 
-export type ReactNativeFeatureFlagsJsOnly = $ReadOnly<{
+export type ReactNativeFeatureFlagsJsOnly = Readonly<{
 ${Object.entries(definitions.jsOnly)
   .map(
     ([flagName, flagConfig]) =>
@@ -46,7 +46,7 @@ ${Object.entries(definitions.jsOnly)
 
 export type ReactNativeFeatureFlagsJsOnlyOverrides = OverridesFor<ReactNativeFeatureFlagsJsOnly>;
 
-export type ReactNativeFeatureFlags = $ReadOnly<{
+export type ReactNativeFeatureFlags = Readonly<{
   ...ReactNativeFeatureFlagsJsOnly,
 ${Object.entries(definitions.common)
   .map(
diff --git a/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js b/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
index e9c3adf7003c..403f339511aa 100644
--- a/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
+++ b/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<d9146c8c9b0c602e4cedb99e6d91558e>>
+ * @generated SignedSource<<609451fd0a38e0f8eaf685e7cf534e27>>
  * @flow strict
  * @noformat
  */
@@ -27,7 +27,7 @@ import {
   setOverrides,
 } from './ReactNativeFeatureFlagsBase';
 
-export type ReactNativeFeatureFlagsJsOnly = $ReadOnly<{
+export type ReactNativeFeatureFlagsJsOnly = Readonly<{
   jsOnlyTestFlag: Getter<boolean>,
   animatedDeferStartOfTimingAnimations: Getter<boolean>,
   animatedShouldDebounceQueueFlush: Getter<boolean>,
@@ -46,7 +46,7 @@ export type ReactNativeFeatureFlagsJsOnly = $ReadOnly<{
 
 export type ReactNativeFeatureFlagsJsOnlyOverrides = OverridesFor<ReactNativeFeatureFlagsJsOnly>;
 
-export type ReactNativeFeatureFlags = $ReadOnly<{
+export type ReactNativeFeatureFlags = Readonly<{
   ...ReactNativeFeatureFlagsJsOnly,
   commonTestFlag: Getter<boolean>,
   commonTestFlagWithoutNativeImplementation: Getter<boolean>,