Test accessibility preferences through notifications and native calls

RCTAccessibilityManager now reads the On/Off Labels, Differentiate
Without Color and Switch Control settings through readers that tests can
replace (RCTAccessibilityManagerSetSystemReaders, in +Internal.h). The
tests post the real UIKit notifications and call getCurrentPreferences
and getRecommendedTimeoutMillis, so they cover the observers, the
deduplication and the native callbacks, not just a helper. This replaces
the two earlier test hooks.

RNTester's preferences row also reads the snapshot and the recommended
timeout again when the app becomes active, because Switch Control has
no change event.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: camilopires

packages/react-native/React/CoreModules/RCTAccessibilityManager+Internal.h

@@ -19,14 +19,14 @@ void RCTAccessibilityManagerSetIsVoiceOverEnabled(
     RCTAccessibilityManager *accessibilityManager,
     BOOL isVoiceOverEnabled);
 
-// Applies a preferences snapshot and sends `preferencesChanged` if it differs
-// from the last one. Returns whether it sent the event.
-BOOL RCTAccessibilityManagerSetPreferences(
-    RCTAccessibilityManager *accessibilityManager,
-    NSDictionary<NSString *, NSNumber *> *preferences);
-
-// The timeout returned by getRecommendedTimeoutMillis.
-double RCTRecommendedTimeoutMillis(double originalTimeout, BOOL isSwitchControlRunning);
+typedef NSDictionary<NSString *, NSNumber *> *_Nonnull (^RCTAccessibilityPreferencesReader)(void);
+typedef BOOL (^RCTSwitchControlReader)(void);
+
+// Replaces how the module reads the system settings behind getPreferences()
+// and getRecommendedTimeoutMillis. Pass nil to read the system again.
+void RCTAccessibilityManagerSetSystemReaders(
+    RCTAccessibilityPreferencesReader _Nullable preferencesReader,
+    RCTSwitchControlReader _Nullable switchControlReader);
 
 RCT_EXTERN_C_END
 

packages/react-native/React/CoreModules/RCTAccessibilityManager.mm

@@ -60,19 +60,26 @@ static NSNotificationName RCTShowBordersStatusDidChangeNotification()
 
 // The settings behind AccessibilityInfo.getPreferences(), named by what the user
 // needs rather than by the iOS setting.
-static NSDictionary<NSString *, NSNumber *> *RCTCurrentAccessibilityPreferences()
+static NSDictionary<NSString *, NSNumber *> *RCTSystemAccessibilityPreferences(void)
 {
   return @{
     @"prefersSwitchLabels" : @(UIAccessibilityIsOnOffSwitchLabelsEnabled()),
     @"prefersNonColorIndicators" : @(UIAccessibilityShouldDifferentiateWithoutColor()),
   };
 }
 
-double RCTRecommendedTimeoutMillis(double originalTimeout, BOOL isSwitchControlRunning)
+// Replaced in tests through RCTAccessibilityManagerSetSystemReaders.
+static RCTAccessibilityPreferencesReader sPreferencesReader = nil;
+static RCTSwitchControlReader sSwitchControlReader = nil;
+
+static NSDictionary<NSString *, NSNumber *> *RCTCurrentAccessibilityPreferences(void)
 {
-  // Moving between elements one switch press at a time is slow, so allow
-  // three times as long while Switch Control is running.
-  return isSwitchControlRunning ? originalTimeout * 3 : originalTimeout;
+  return sPreferencesReader != nil ? sPreferencesReader() : RCTSystemAccessibilityPreferences();
+}
+
+static BOOL RCTIsSwitchControlRunning(void)
+{
+  return sSwitchControlReader != nil ? sSwitchControlReader() : UIAccessibilityIsSwitchControlRunning();
 }
 
 @implementation RCTAccessibilityManager
@@ -291,17 +298,15 @@ - (void)preferencesStatusDidChange:(__unused NSNotification *)notification
   [self _setPreferences:RCTCurrentAccessibilityPreferences()];
 }
 
-- (BOOL)_setPreferences:(NSDictionary<NSString *, NSNumber *> *)preferences
+- (void)_setPreferences:(NSDictionary<NSString *, NSNumber *> *)preferences
 {
-  if ([_preferences isEqualToDictionary:preferences]) {
-    return NO;
-  }
-  _preferences = [preferences copy];
+  if (![_preferences isEqualToDictionary:preferences]) {
+    _preferences = [preferences copy];
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
-  [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"preferencesChanged" body:_preferences];
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"preferencesChanged" body:_preferences];
 #pragma clang diagnostic pop
-  return YES;
+  }
 }
 
 - (void)voiceVoiceOverStatusDidChange:(__unused NSNotification *)notification
@@ -525,7 +530,9 @@ - (void)getCurrentPreferences:(RCTResponseSenderBlock)onSuccess onError:(__unuse
 
 - (void)getRecommendedTimeoutMillis:(double)mSec onSuccess:(RCTResponseSenderBlock)onSuccess
 {
-  onSuccess(@[ @(RCTRecommendedTimeoutMillis(mSec, UIAccessibilityIsSwitchControlRunning())) ]);
+  // Moving between elements one switch press at a time is slow, so allow
+  // three times as long while Switch Control is running.
+  onSuccess(@[ @(RCTIsSwitchControlRunning() ? mSec * 3 : mSec) ]);
 }
 
 - (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:
@@ -543,11 +550,12 @@ void RCTAccessibilityManagerSetIsVoiceOverEnabled(
   [accessibilityManager _setIsVoiceOverEnabled:isVoiceOverEnabled];
 }
 
-BOOL RCTAccessibilityManagerSetPreferences(
-    RCTAccessibilityManager *accessibilityManager,
-    NSDictionary<NSString *, NSNumber *> *preferences)
+void RCTAccessibilityManagerSetSystemReaders(
+    RCTAccessibilityPreferencesReader _Nullable preferencesReader,
+    RCTSwitchControlReader _Nullable switchControlReader)
 {
-  return [accessibilityManager _setPreferences:preferences];
+  sPreferencesReader = preferencesReader;
+  sSwitchControlReader = switchControlReader;
 }
 
 @end

packages/rn-tester/RNTesterUnitTests/RCTAccessibilityManagerTests.m

@@ -5,15 +5,26 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#import <UIKit/UIKit.h>
 #import <XCTest/XCTest.h>
 
 #import <React/RCTAccessibilityManager.h>
 #import <React/RCTBridgeModule.h>
 
-extern BOOL RCTAccessibilityManagerSetPreferences(
-    RCTAccessibilityManager *accessibilityManager,
-    NSDictionary<NSString *, NSNumber *> *preferences);
-extern double RCTRecommendedTimeoutMillis(double originalTimeout, BOOL isSwitchControlRunning);
+// From RCTAccessibilityManager+Internal.h.
+typedef NSDictionary<NSString *, NSNumber *> * (^RCTAccessibilityPreferencesReader)(void);
+typedef BOOL (^RCTSwitchControlReader)(void);
+extern void RCTAccessibilityManagerSetSystemReaders(
+    RCTAccessibilityPreferencesReader preferencesReader,
+    RCTSwitchControlReader switchControlReader);
+
+// The native module methods JS calls, from the generated spec.
+@interface RCTAccessibilityManager (RCTAccessibilityManagerTests)
+
+- (void)getCurrentPreferences:(RCTResponseSenderBlock)onSuccess onError:(RCTResponseSenderBlock)onError;
+- (void)getRecommendedTimeoutMillis:(double)mSec onSuccess:(RCTResponseSenderBlock)onSuccess;
+
+@end
 
 // Records the device events the module sends.
 @interface RCTAccessibilityManagerTestsEventDispatcher : NSObject
@@ -65,48 +76,108 @@ @implementation RCTAccessibilityManagerTests {
   RCTAccessibilityManagerTestsEventDispatcher *_eventDispatcher;
   // The module holds its registry weakly.
   RCTAccessibilityManagerTestsModuleRegistry *_moduleRegistry;
+  NSDictionary<NSString *, NSNumber *> *_systemPreferences;
+  BOOL _isSwitchControlRunning;
 }
 
 - (void)setUp
 {
   [super setUp];
+  _systemPreferences = @{@"prefersSwitchLabels" : @NO, @"prefersNonColorIndicators" : @NO};
+  _isSwitchControlRunning = NO;
+  __weak RCTAccessibilityManagerTests *weakSelf = self;
+  RCTAccessibilityManagerSetSystemReaders(
+      ^NSDictionary<NSString *, NSNumber *> * {
+        RCTAccessibilityManagerTests *strongSelf = weakSelf;
+        return strongSelf ? strongSelf->_systemPreferences : @{};
+      },
+      ^BOOL {
+        RCTAccessibilityManagerTests *strongSelf = weakSelf;
+        return strongSelf ? strongSelf->_isSwitchControlRunning : NO;
+      });
+
   _eventDispatcher = [RCTAccessibilityManagerTestsEventDispatcher new];
   _moduleRegistry = [RCTAccessibilityManagerTestsModuleRegistry new];
   _moduleRegistry.eventDispatcher = _eventDispatcher;
   _manager = [RCTAccessibilityManager new];
   _manager.moduleRegistry = _moduleRegistry;
 }
 
-- (void)testRecommendedTimeoutIsLongerWhileSwitchControlIsRunning
+- (void)tearDown
 {
-  XCTAssertEqual(RCTRecommendedTimeoutMillis(4000, YES), 12000);
-  XCTAssertEqual(RCTRecommendedTimeoutMillis(4000, NO), 4000);
-  XCTAssertEqual(RCTRecommendedTimeoutMillis(0, YES), 0);
+  RCTAccessibilityManagerSetSystemReaders(nil, nil);
+  _manager = nil;
+  [super tearDown];
 }
 
-- (void)testUnchangedPreferencesSendNoEvent
+- (NSDictionary *)currentPreferences
 {
-  NSDictionary *preferences = @{@"prefersSwitchLabels" : @YES, @"prefersNonColorIndicators" : @NO};
+  __block NSDictionary *preferences = nil;
+  [_manager
+      getCurrentPreferences:^(NSArray *response) {
+        preferences = response.firstObject;
+      }
+      onError:^(__unused NSArray *response) {
+        XCTFail(@"getCurrentPreferences failed");
+      }];
+  return preferences;
+}
 
-  RCTAccessibilityManagerSetPreferences(_manager, preferences);
-  [_eventDispatcher.events removeAllObjects];
-  BOOL sent = RCTAccessibilityManagerSetPreferences(_manager, [preferences copy]);
+- (NSNumber *)recommendedTimeoutFor:(double)mSec
+{
+  __block NSNumber *timeout = nil;
+  [_manager getRecommendedTimeoutMillis:mSec
+                              onSuccess:^(NSArray *response) {
+                                timeout = response.firstObject;
+                              }];
+  return timeout;
+}
 
-  XCTAssertFalse(sent);
-  XCTAssertEqual(_eventDispatcher.events.count, 0);
+- (void)testGetCurrentPreferencesReturnsTheSettingsAtStartup
+{
+  XCTAssertEqualObjects(
+      [self currentPreferences], (@{@"prefersSwitchLabels" : @NO, @"prefersNonColorIndicators" : @NO}));
+}
+
+- (void)testOnOffSwitchLabelsChangeSendsTheWholeSnapshot
+{
+  _systemPreferences = @{@"prefersSwitchLabels" : @YES, @"prefersNonColorIndicators" : @NO};
+  [[NSNotificationCenter defaultCenter] postNotificationName:UIAccessibilityOnOffSwitchLabelsDidChangeNotification
+                                                      object:nil];
+
+  XCTAssertEqualObjects(_eventDispatcher.events, (@[ @[ @"preferencesChanged", _systemPreferences ] ]));
+  XCTAssertEqualObjects([self currentPreferences], _systemPreferences);
+}
+
+- (void)testDifferentiateWithoutColorChangeSendsTheWholeSnapshot
+{
+  _systemPreferences = @{@"prefersSwitchLabels" : @NO, @"prefersNonColorIndicators" : @YES};
+  [[NSNotificationCenter defaultCenter]
+      postNotificationName:UIAccessibilityShouldDifferentiateWithoutColorDidChangeNotification
+                    object:nil];
+
+  XCTAssertEqualObjects(_eventDispatcher.events, (@[ @[ @"preferencesChanged", _systemPreferences ] ]));
+  XCTAssertEqualObjects([self currentPreferences], _systemPreferences);
 }
 
-- (void)testChangedPreferencesSendTheWholeSnapshot
+- (void)testNotificationWithoutAChangeSendsNoEvent
 {
-  RCTAccessibilityManagerSetPreferences(_manager, @{@"prefersSwitchLabels" : @NO, @"prefersNonColorIndicators" : @NO});
-  [_eventDispatcher.events removeAllObjects];
+  [[NSNotificationCenter defaultCenter] postNotificationName:UIAccessibilityOnOffSwitchLabelsDidChangeNotification
+                                                      object:nil];
+  [[NSNotificationCenter defaultCenter]
+      postNotificationName:UIAccessibilityShouldDifferentiateWithoutColorDidChangeNotification
+                    object:nil];
+
+  XCTAssertEqual(_eventDispatcher.events.count, 0);
+}
 
-  NSDictionary *changed = @{@"prefersSwitchLabels" : @NO, @"prefersNonColorIndicators" : @YES};
-  BOOL sent = RCTAccessibilityManagerSetPreferences(_manager, changed);
+- (void)testRecommendedTimeoutIsLongerWhileSwitchControlIsRunning
+{
+  XCTAssertEqualObjects([self recommendedTimeoutFor:4000], @4000);
 
-  XCTAssertTrue(sent);
-  XCTAssertEqual(_eventDispatcher.events.count, 1);
-  XCTAssertEqualObjects(_eventDispatcher.events.firstObject, (@[ @"preferencesChanged", changed ]));
+  _isSwitchControlRunning = YES;
+  XCTAssertEqualObjects([self recommendedTimeoutFor:4000], @12000);
+  XCTAssertEqualObjects([self recommendedTimeoutFor:0], @0);
 }
 
 @end

packages/rn-tester/js/examples/Accessibility/AccessibilityExample.js

@@ -27,6 +27,7 @@ import {createRef, useEffect, useRef, useState} from 'react';
 import {
   AccessibilityInfo,
   Alert,
+  AppState,
   Button,
   Image,
   ImageBackground,
@@ -1672,14 +1673,25 @@ function PreferencesStatusExample(): React.Node {
         setLastEvent(newPreferences);
       },
     );
-    // $FlowFixMe[unused-promise]
-    AccessibilityInfo.getPreferences().then(setPreferences);
-    // $FlowFixMe[unused-promise]
-    AccessibilityInfo.getRecommendedTimeoutMillis(4000).then(
-      setRecommendedTimeout,
-    );
+    // Switch Control has no change event, so read again when the app comes
+    // back from Settings.
+    const read = () => {
+      // $FlowFixMe[unused-promise]
+      AccessibilityInfo.getPreferences().then(setPreferences);
+      // $FlowFixMe[unused-promise]
+      AccessibilityInfo.getRecommendedTimeoutMillis(4000).then(
+        setRecommendedTimeout,
+      );
+    };
+    read();
+    const appStateListener = AppState.addEventListener('change', state => {
+      if (state === 'active') {
+        read();
+      }
+    });
     return function cleanup() {
       listener.remove();
+      appStateListener.remove();
     };
   }, []);
   return (