Remove gating for subview clipping

Summary:
changelog: [internal]

Remove gating for subview clipping

Reviewed By: philIip

Differential Revision: D32594194

fbshipit-source-id: e35e698cc3303f289cdd44a7f34274ea046dfd81

React/Base/RCTConstants.h

@@ -15,9 +15,3 @@ RCT_EXTERN NSString *const RCTUserInterfaceStyleDidChangeNotificationTraitCollec
  */
 RCT_EXTERN BOOL RCTExperimentGetPreemptiveViewAllocationDisabled(void);
 RCT_EXTERN void RCTExperimentSetPreemptiveViewAllocationDisabled(BOOL value);
-
-/*
- * Remove clipped subviews
- */
-RCT_EXTERN BOOL RCTGetRemoveClippedSubviewsEnabled(void);
-RCT_EXTERN void RCTSetRemoveClippedSubviewsEnabled(BOOL value);

React/Base/RCTConstants.m

@@ -24,18 +24,3 @@ void RCTExperimentSetPreemptiveViewAllocationDisabled(BOOL value)
 {
   RCTExperimentPreemptiveViewAllocationDisabled = value;
 }
-
-/*
- * Remove clipped subviews
- */
-static BOOL RCTRemoveClippedSubviewsEnabled = NO;
-
-BOOL RCTGetRemoveClippedSubviewsEnabled(void)
-{
-  return RCTRemoveClippedSubviewsEnabled;
-}
-
-void RCTSetRemoveClippedSubviewsEnabled(BOOL value)
-{
-  RCTRemoveClippedSubviewsEnabled = value;
-}

React/Fabric/Mounting/ComponentViews/ScrollView/RCTScrollViewComponentView.mm

@@ -87,8 +87,6 @@ static void RCTSendPaperScrollEvent_DEPRECATED(UIScrollView *scrollView, NSInteg
   BOOL _isUserTriggeredScrolling;
 
   CGPoint _contentOffsetWhenClipped;
-  NSMutableArray<UIView<RCTComponentViewProtocol> *> *_childComponentViews;
-  BOOL _subviewClippingEnabled;
 }
 
 + (RCTScrollViewComponentView *_Nullable)findScrollViewComponentViewForView:(UIView *)view
@@ -105,15 +103,12 @@ static void RCTSendPaperScrollEvent_DEPRECATED(UIScrollView *scrollView, NSInteg
     static const auto defaultProps = std::make_shared<const ScrollViewProps>();
     _props = defaultProps;
 
-    _childComponentViews = [NSMutableArray new];
-
     _scrollView = [[RCTEnhancedScrollView alloc] initWithFrame:self.bounds];
     _scrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
     _scrollView.delaysContentTouches = NO;
     ((RCTEnhancedScrollView *)_scrollView).overridingDelegate = self;
     _isUserTriggeredScrolling = NO;
     [self addSubview:_scrollView];
-    _subviewClippingEnabled = RCTGetRemoveClippedSubviewsEnabled();
 
     _containerView = [[UIView alloc] initWithFrame:CGRectZero];
     [_scrollView addSubview:_containerView];
@@ -324,24 +319,11 @@ static void RCTSendPaperScrollEvent_DEPRECATED(UIScrollView *scrollView, NSInteg
 
 - (void)mountChildComponentView:(UIView<RCTComponentViewProtocol> *)childComponentView index:(NSInteger)index
 {
-  if (_subviewClippingEnabled) {
   [_containerView insertSubview:childComponentView atIndex:index];
-  } else {
-    [_childComponentViews insertObject:childComponentView atIndex:index];
-  }
 }
 
 - (void)unmountChildComponentView:(UIView<RCTComponentViewProtocol> *)childComponentView index:(NSInteger)index
 {
-  if (!_subviewClippingEnabled) {
-    RCTAssert(
-        [_childComponentViews objectAtIndex:index] == childComponentView,
-        @"Attempt to unmount improperly mounted component view.");
-    [_childComponentViews removeObjectAtIndex:index];
-  }
-
-  // In addition to removing a view from `_childComponentViews`,
-  // we have to unmount views immediately to not mess with recycling.
   [childComponentView removeFromSuperview];
 }
 
@@ -626,68 +608,8 @@ static void RCTSendPaperScrollEvent_DEPRECATED(UIScrollView *scrollView, NSInteg
 
 - (void)_remountChildren
 {
-  if (_subviewClippingEnabled) {
   [_scrollView updateClippedSubviewsWithClipRect:CGRectInset(_scrollView.bounds, -kClippingLeeway, -kClippingLeeway)
                                   relativeToView:_scrollView];
-  } else {
-    CGRect visibleFrame = [_scrollView convertRect:_scrollView.bounds toView:_containerView];
-    visibleFrame = CGRectInset(visibleFrame, -kClippingLeeway, -kClippingLeeway);
-
-    // `zoomScale` is negative in RTL. Absolute value is needed.
-    CGFloat scale = 1.0 / std::abs(_scrollView.zoomScale);
-    visibleFrame.origin.x *= scale;
-    visibleFrame.origin.y *= scale;
-    visibleFrame.size.width *= scale;
-    visibleFrame.size.height *= scale;
-#ifndef NDEBUG
-    NSMutableArray<UIView<RCTComponentViewProtocol> *> *expectedSubviews = [NSMutableArray new];
-#endif
-
-    NSInteger mountedIndex = 0;
-    for (UIView *componentView in _childComponentViews) {
-      BOOL shouldBeMounted = YES;
-      BOOL isMounted = componentView.superview != nil;
-
-      // It's simpler and faster to not mess with views that are not `RCTViewComponentView` subclasses.
-      if ([componentView isKindOfClass:[RCTViewComponentView class]]) {
-        RCTViewComponentView *viewComponentView = (RCTViewComponentView *)componentView;
-        auto layoutMetrics = viewComponentView->_layoutMetrics;
-
-        if (layoutMetrics.overflowInset == EdgeInsets{}) {
-          shouldBeMounted = CGRectIntersectsRect(visibleFrame, componentView.frame);
-        }
-      }
-
-      if (shouldBeMounted != isMounted) {
-        if (shouldBeMounted) {
-          [_containerView insertSubview:componentView atIndex:mountedIndex];
-        } else {
-          [componentView removeFromSuperview];
-        }
-      }
-
-      if (shouldBeMounted) {
-        mountedIndex++;
-      }
-
-#ifndef NDEBUG
-      if (shouldBeMounted) {
-        [expectedSubviews addObject:componentView];
-      }
-#endif
-    }
-
-#ifndef NDEBUG
-    RCTAssert(
-        _containerView.subviews.count == expectedSubviews.count,
-        @"-[RCTScrollViewComponentView _remountChildren]: Inconsistency detected.");
-    for (NSInteger i = 0; i < expectedSubviews.count; i++) {
-      RCTAssert(
-          [_containerView.subviews objectAtIndex:i] == [expectedSubviews objectAtIndex:i],
-          @"-[RCTScrollViewComponentView _remountChildren]: Inconsistency detected.");
-    }
-#endif
-  }
 }
 
 #pragma mark - RCTScrollableProtocol

React/Fabric/Mounting/ComponentViews/View/RCTViewComponentView.mm

@@ -193,8 +193,7 @@ using namespace facebook::react;
     needsInvalidateLayer = YES;
   }
 
-  if (RCTGetRemoveClippedSubviewsEnabled() &&
-      oldViewProps.removeClippedSubviews != newViewProps.removeClippedSubviews) {
+  if (oldViewProps.removeClippedSubviews != newViewProps.removeClippedSubviews) {
     _removeClippedSubviews = newViewProps.removeClippedSubviews;
     if (_removeClippedSubviews && self.subviews.count > 0) {
       _reactSubviews = [NSMutableArray arrayWithArray:self.subviews];

React/Fabric/RCTSurfacePresenter.mm

@@ -255,10 +255,6 @@ static BackgroundExecutor RCTGetBackgroundExecutor()
     RCTExperimentSetPreemptiveViewAllocationDisabled(YES);
   }
 
-  if (reactNativeConfig && reactNativeConfig->getBool("react_fabric:enable_remove_clipped_subviews_ios")) {
-    RCTSetRemoveClippedSubviewsEnabled(YES);
-  }
-
   auto componentRegistryFactory =
       [factory = wrapManagedObject(_mountingManager.componentViewRegistry.componentViewFactory)](
           EventDispatcher::Weak const &eventDispatcher, ContextContainer::Shared const &contextContainer) {