chore(macOS): Consolidate RCTAccessibilityManager between iOS and macOS (#2400)

## Summary:

This PR attempts to solve two problems:

1. We have had a forked AccessibilityManager module for macOS for a
while. In general, I prefer ifdefing rather than forking so that we get
changes to the iOS code during merges. Let's combine the files.

2. I want to cleanup macOS's "highContrast" API in AccessibilityInfo so
it can be upstreamed, so that RNW can follow it and we have a
cross-platform way to get high contrast state. Luckily, the API we have
for macOS can be ported to iOS, so I did that. Unluckily, someone
already did that (see:
facebook#46826 ) and used the iOS
specific name "Darker system colors" instead of something like "increase
contrast" or "high contrast". So I'll probably need to add my API
upstream, deprecate that one, and then remove it in a future release.

Author: Saadnajmi

packages/react-native/Libraries/Components/AccessibilityInfo/AccessibilityInfo.js

@@ -71,12 +71,12 @@ const EventNames: Map<
       ['boldTextChanged', 'boldTextChanged'],
       ['change', 'screenReaderChanged'],
       ['grayscaleChanged', 'grayscaleChanged'],
-      ['highContrastChanged', 'highContrastChanged'], // [macOS]
       ['invertColorsChanged', 'invertColorsChanged'],
       ['reduceMotionChanged', 'reduceMotionChanged'],
       ['reduceTransparencyChanged', 'reduceTransparencyChanged'],
       ['screenReaderChanged', 'screenReaderChanged'],
       ['darkerSystemColorsChanged', 'darkerSystemColorsChanged'],
+      ['highContrastChanged', 'highContrastChanged'], // [macOS]
     ]);
 
 /**
@@ -152,7 +152,7 @@ const AccessibilityInfo = {
    * macOS only
    */
   isHighContrastEnabled: function (): Promise<boolean> {
-    if (Platform.OS === 'macos') {
+    if (Platform.OS === 'macos' || Platform.OS === 'ios') {
       return new Promise((resolve, reject) => {
         if (NativeAccessibilityManagerApple) {
           NativeAccessibilityManagerApple.getCurrentHighContrastState(

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

@@ -17,11 +17,11 @@
 
 #import "CoreModulesPlugins.h"
 
-#if !TARGET_OS_OSX // [macOS]
-
 NSString *const RCTAccessibilityManagerDidUpdateMultiplierNotification =
     @"RCTAccessibilityManagerDidUpdateMultiplierNotification";
 
+static void *AccessibilityVoiceOverChangeContext = &AccessibilityVoiceOverChangeContext; // [macOS]
+
 @interface RCTAccessibilityManager () <NativeAccessibilityManagerSpec>
 
 @property (nonatomic, copy) NSString *contentSizeCategory;
@@ -47,6 +47,7 @@ - (instancetype)init
   if (self = [super init]) {
     _multiplier = 1.0;
 
+#if !TARGET_OS_OSX // [macOS]
     // TODO: can this be moved out of the startup path?
     [[NSNotificationCenter defaultCenter] addObserver:self
                                              selector:@selector(didReceiveNewContentSizeCategory:)
@@ -92,7 +93,18 @@ - (instancetype)init
                                              selector:@selector(voiceVoiceOverStatusDidChange:)
                                                  name:UIAccessibilityVoiceOverStatusDidChangeNotification
                                                object:nil];
+#else // [macOS
+        [[NSWorkspace sharedWorkspace] addObserver:self
+                                        forKeyPath:@"voiceOverEnabled"
+                                           options:(NSKeyValueObservingOptionNew | NSKeyValueObservingOptionOld)
+                                           context:AccessibilityVoiceOverChangeContext];
+        [[[NSWorkspace sharedWorkspace] notificationCenter] addObserver:self
+                                                 selector:@selector(accessibilityDisplayOptionsChange:)
+                                                     name:NSWorkspaceAccessibilityDisplayOptionsDidChangeNotification
+                                                   object:nil];
+#endif // macOS]
 
+#if !TARGET_OS_OSX // [macOS]
     self.contentSizeCategory = RCTSharedApplication().preferredContentSizeCategory;
     _isBoldTextEnabled = UIAccessibilityIsBoldTextEnabled();
     _isGrayscaleEnabled = UIAccessibilityIsGrayscaleEnabled();
@@ -101,10 +113,29 @@ - (instancetype)init
     _isDarkerSystemColorsEnabled = UIAccessibilityDarkerSystemColorsEnabled();
     _isReduceTransparencyEnabled = UIAccessibilityIsReduceTransparencyEnabled();
     _isVoiceOverEnabled = UIAccessibilityIsVoiceOverRunning();
+    _isHighContrastEnabled = UIAccessibilityDarkerSystemColorsEnabled(); // [macOS] Implement high Contrast for iOS
+#else // [macOS
+    NSWorkspace *sharedWorkspace = [NSWorkspace sharedWorkspace];
+    _isInvertColorsEnabled = [sharedWorkspace accessibilityDisplayShouldInvertColors];
+    _isReduceMotionEnabled = [sharedWorkspace accessibilityDisplayShouldReduceMotion];
+    _isReduceTransparencyEnabled = [sharedWorkspace accessibilityDisplayShouldReduceTransparency];
+    _isVoiceOverEnabled = [sharedWorkspace isVoiceOverEnabled];
+    _isHighContrastEnabled = [sharedWorkspace accessibilityDisplayShouldIncreaseContrast];
+#endif // macOS]
   }
   return self;
 }
 
+#if TARGET_OS_OSX // [macOS
+- (void)dealloc
+{
+  [[NSWorkspace sharedWorkspace] removeObserver:self
+                                     forKeyPath:@"voiceOverEnabled"
+                                        context:AccessibilityVoiceOverChangeContext];
+}
+#endif // macOS]
+
+#if !TARGET_OS_OSX // [macOS]
 - (void)didReceiveNewContentSizeCategory:(NSNotification *)note
 {
   self.contentSizeCategory = note.userInfo[UIContentSizeCategoryNewValueKey];
@@ -186,6 +217,11 @@ - (void)darkerSystemColorsDidChange:(__unused NSNotification *)notification
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
     [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"darkerSystemColorsChanged"
                                                                           body:@(_isDarkerSystemColorsEnabled)];
+    // [macOS Also fire the highContrastChanged event for iOS
+    _isHighContrastEnabled = newDarkerSystemColorsEnabled;
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"highContrastChanged"
+                                                                          body:@(_isDarkerSystemColorsEnabled)];
+    // macOS]
 
 #pragma clang diagnostic pop
   }
@@ -209,6 +245,71 @@ - (void)voiceVoiceOverStatusDidChange:(__unused NSNotification *)notification
   BOOL isVoiceOverEnabled = UIAccessibilityIsVoiceOverRunning();
   [self _setIsVoiceOverEnabled:isVoiceOverEnabled];
 }
+#else // [macOS
+- (void)accessibilityDisplayOptionsChange:(NSNotification *)notification
+{
+  BOOL newInvertColorsEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldInvertColors];
+  BOOL newReduceMotionEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceMotion];
+  BOOL newReduceTransparencyEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldReduceTransparency];
+  BOOL newHighContrastEnabled = [[NSWorkspace sharedWorkspace] accessibilityDisplayShouldIncreaseContrast];
+  
+
+  if (_isHighContrastEnabled != newHighContrastEnabled) {
+    _isHighContrastEnabled = newHighContrastEnabled;
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"highContrastChanged"
+                                                                          body:@(_isHighContrastEnabled)];
+#pragma clang diagnostic pop
+  }
+  if (_isInvertColorsEnabled != newInvertColorsEnabled) {
+    _isInvertColorsEnabled = newInvertColorsEnabled;
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"invertColorsChanged"
+                                                                          body:@(_isInvertColorsEnabled)];
+#pragma clang diagnostic pop
+  }
+  if (_isReduceMotionEnabled != newReduceMotionEnabled) {
+    _isReduceMotionEnabled = newReduceMotionEnabled;
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"reduceMotionChanged"
+                                                                          body:@(_isReduceMotionEnabled)];
+#pragma clang diagnostic pop
+  }
+  if (_isReduceTransparencyEnabled != newReduceTransparencyEnabled) {
+    _isReduceTransparencyEnabled = newReduceTransparencyEnabled;
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+    [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"reduceTransparencyChanged"
+                                                                          body:@(_isReduceTransparencyEnabled)];
+#pragma clang diagnostic pop
+  }
+}
+
+- (void)observeValueForKeyPath:(NSString *)keyPath
+                      ofObject:(id)object
+                        change:(NSDictionary *)change
+                       context:(void *)context {
+  if (context == AccessibilityVoiceOverChangeContext) {
+    BOOL newIsVoiceOverEnabled = [[NSWorkspace sharedWorkspace] isVoiceOverEnabled];
+    if (_isVoiceOverEnabled != newIsVoiceOverEnabled) {
+      _isVoiceOverEnabled = newIsVoiceOverEnabled;
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+      [[_moduleRegistry moduleForName:"EventDispatcher"] sendDeviceEventWithName:@"screenReaderChanged"
+                                                                            body:@(_isVoiceOverEnabled)];
+#pragma clang diagnostic pop
+    }
+  } else {
+    [super observeValueForKeyPath:keyPath
+                         ofObject:object
+                           change:change
+                          context:context];
+  }
+}
+#endif // macOS]
 
 - (void)_setIsVoiceOverEnabled:(BOOL)isVoiceOverEnabled
 {
@@ -257,6 +358,7 @@ - (void)setMultipliers:(NSDictionary<NSString *, NSNumber *> *)multipliers
 
 - (NSDictionary<NSString *, NSNumber *> *)multipliers
 {
+#if !TARGET_OS_OSX // [macOS]
   if (_multipliers == nil) {
     _multipliers = @{
       UIContentSizeCategoryExtraSmall : @0.823,
@@ -273,6 +375,7 @@ - (void)setMultipliers:(NSDictionary<NSString *, NSNumber *> *)multipliers
       UIContentSizeCategoryAccessibilityExtraExtraExtraLarge : @3.571
     };
   }
+#endif // [macOS]
   return _multipliers;
 }
 
@@ -281,6 +384,7 @@ - (void)setMultipliers:(NSDictionary<NSString *, NSNumber *> *)multipliers
                       JSMultipliers)
 {
   NSMutableDictionary<NSString *, NSNumber *> *multipliers = [NSMutableDictionary new];
+#if !TARGET_OS_OSX // [macOS]
   setMultipliers(multipliers, UIContentSizeCategoryExtraSmall, JSMultipliers.extraSmall());
   setMultipliers(multipliers, UIContentSizeCategorySmall, JSMultipliers.small());
   setMultipliers(multipliers, UIContentSizeCategoryMedium, JSMultipliers.medium());
@@ -297,6 +401,7 @@ - (void)setMultipliers:(NSDictionary<NSString *, NSNumber *> *)multipliers
       multipliers,
       UIContentSizeCategoryAccessibilityExtraExtraExtraLarge,
       JSMultipliers.accessibilityExtraExtraExtraLarge());
+#endif // [macOS]
   self.multipliers = multipliers;
 }
 
@@ -313,20 +418,38 @@ static void setMultipliers(
 RCT_EXPORT_METHOD(setAccessibilityFocus : (double)reactTag)
 {
   dispatch_async(dispatch_get_main_queue(), ^{
-    UIView *view = [self.viewRegistry_DEPRECATED viewForReactTag:@(reactTag)];
+    RCTPlatformView *view = [self.viewRegistry_DEPRECATED viewForReactTag:@(reactTag)]; // [macOS]
+#if !TARGET_OS_OSX // [macOS]
     UIAccessibilityPostNotification(UIAccessibilityLayoutChangedNotification, view);
+#else // [macOS
+    [[view window] makeFirstResponder:view];
+    NSAccessibilityPostNotification(view, NSAccessibilityLayoutChangedNotification);
+#endif // macOS]
   });
 }
 
 RCT_EXPORT_METHOD(announceForAccessibility : (NSString *)announcement)
 {
+#if !TARGET_OS_OSX // [macOS]
   UIAccessibilityPostNotification(UIAccessibilityAnnouncementNotification, announcement);
+#else // [macOS
+  dispatch_async(dispatch_get_main_queue(), ^{
+    NSAccessibilityPostNotificationWithUserInfo(
+                                                NSApp,
+                                                NSAccessibilityAnnouncementRequestedNotification,
+                                                @{NSAccessibilityAnnouncementKey : announcement,
+                                                  NSAccessibilityPriorityKey : @(NSAccessibilityPriorityHigh)
+                                                }
+                                                );
+  });
+#endif // macOS]
 }
 
 RCT_EXPORT_METHOD(announceForAccessibilityWithOptions
                   : (NSString *)announcement options
                   : (JS::NativeAccessibilityManager::SpecAnnounceForAccessibilityWithOptionsOptions &)options)
 {
+#if !TARGET_OS_OSX // [macOS]
   NSMutableDictionary<NSString *, NSNumber *> *attrsDictionary = [NSMutableDictionary new];
   if (options.queue()) {
     attrsDictionary[UIAccessibilitySpeechAttributeQueueAnnouncement] = @(*(options.queue()) ? YES : NO);
@@ -339,6 +462,18 @@ static void setMultipliers(
   } else {
     UIAccessibilityPostNotification(UIAccessibilityAnnouncementNotification, announcement);
   }
+#else // [macOS
+  NSAccessibilityPriorityLevel announcementPriority = options.queue() ? NSAccessibilityPriorityLow : NSAccessibilityPriorityHigh;
+  dispatch_async(dispatch_get_main_queue(), ^{
+    NSAccessibilityPostNotificationWithUserInfo(
+                                                NSApp,
+                                                NSAccessibilityAnnouncementRequestedNotification,
+                                                @{NSAccessibilityAnnouncementKey : announcement,
+                                                  NSAccessibilityPriorityKey : @(announcementPriority)
+                                                }
+                                                );
+  });
+#endif // macOS]
 }
 
 RCT_EXPORT_METHOD(getMultiplier : (RCTResponseSenderBlock)callback)
@@ -387,11 +522,15 @@ static void setMultipliers(
                   : (RCTResponseSenderBlock)onSuccess onError
                   : (__unused RCTResponseSenderBlock)onError)
 {
+#if !TARGET_OS_OSX // [macOS]
   if (@available(iOS 14.0, *)) {
     onSuccess(@[ @(UIAccessibilityPrefersCrossFadeTransitions()) ]);
   } else {
     onSuccess(@[ @(false) ]);
   }
+#else // [macOS
+  onSuccess(@[ @(false) ]); // iOS only
+#endif // macOS]
 }
 
 RCT_EXPORT_METHOD(getCurrentReduceTransparencyState
@@ -408,6 +547,16 @@ static void setMultipliers(
   onSuccess(@[ @(_isVoiceOverEnabled) ]);
 }
 
+// [macOS Implement for both iOS and macOS
+RCT_EXPORT_METHOD(getCurrentHighContrastState
+                  : (RCTResponseSenderBlock)onSuccess onError
+                  : (__unused RCTResponseSenderBlock)onError)
+{
+  onSuccess(@[ @(_isHighContrastEnabled) ]);
+}
+// macOS]
+
+
 - (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:
     (const facebook::react::ObjCTurboModule::InitParams &)params
 {
@@ -447,4 +596,3 @@ Class RCTAccessibilityManagerCls(void)
 {
   return RCTAccessibilityManager.class;
 }
-#endif // [macOS]