From 4185fc4f4e85c898c4762e11c523bdf62a7703dd Mon Sep 17 00:00:00 2001
From: Christoph Purrer <chpurrer@meta.com>
Date: Fri, 30 Oct 2026 23:23:40 -0700
Subject: [PATCH] Compile out RCTViewManager under
 RCT_REMOVE_LEGACY_COMPONENT_INTEROP - WIP (#59651)

Summary:

Consumers who opt into `RCT_REMOVE_LEGACY_COMPONENT_INTEROP` now get the Paper `RCTViewManager` base class compiled out, along with its property macros and the supporting `RCTComponentData` implementation. Any remaining subclass fails at compile time instead of shipping unreachable code. The flag defaults to off, so default builds are unaffected.

Changelog:
[iOS][Added] - Compile out the Paper `RCTViewManager` base when `RCT_REMOVE_LEGACY_COMPONENT_INTEROP` is set

Differential Revision: D128434146
---
 packages/react-native/React/Views/RCTComponentData.h          | 4 ++++
 packages/react-native/React/Views/RCTComponentData.mm         | 4 ++++
 packages/react-native/React/Views/RCTViewManager.h            | 4 ++++
 packages/react-native/React/Views/RCTViewManager.m            | 4 ++++
 .../NativeComponentExample/ios/RCTInteropTestViewManager.h    | 4 ++++
 .../NativeComponentExample/ios/RCTInteropTestViewManager.m    | 4 ++++
 .../ios/RNTMyLegacyNativeViewManager.mm                       | 4 ++++
 .../NativeComponentExample/ios/RNTMyNativeViewManager.mm      | 4 ++++
 8 files changed, 32 insertions(+)

diff --git a/packages/react-native/React/Views/RCTComponentData.h b/packages/react-native/React/Views/RCTComponentData.h
index e5c22a19c474..5f6ce2e8e2c5 100644
--- a/packages/react-native/React/Views/RCTComponentData.h
+++ b/packages/react-native/React/Views/RCTComponentData.h
@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 #import <Foundation/Foundation.h>
 
 #import <React/RCTComponent.h>
@@ -48,3 +50,5 @@ NS_ASSUME_NONNULL_BEGIN
 RCT_EXTERN NSString *RCTViewManagerModuleNameForClass(Class managerClass);
 
 NS_ASSUME_NONNULL_END
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/react-native/React/Views/RCTComponentData.mm b/packages/react-native/React/Views/RCTComponentData.mm
index c857b4021478..70425ad70366 100644
--- a/packages/react-native/React/Views/RCTComponentData.mm
+++ b/packages/react-native/React/Views/RCTComponentData.mm
@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 #import "RCTComponentData.h"
 
 #import <objc/message.h>
@@ -550,3 +552,5 @@ - (void)setProps:(NSDictionary<NSString *, id> *)props forView:(id<RCTComponent>
 }
 
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/react-native/React/Views/RCTViewManager.h b/packages/react-native/React/Views/RCTViewManager.h
index ed17a436d861..014d30d888d3 100644
--- a/packages/react-native/React/Views/RCTViewManager.h
+++ b/packages/react-native/React/Views/RCTViewManager.h
@@ -21,6 +21,8 @@
 
 typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNumber *, UIView *> *viewRegistry);
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 @interface RCTViewManager : NSObject <RCTBridgeModule>
 
 /**
@@ -119,3 +121,5 @@ typedef void (^RCTViewManagerUIBlock)(RCTUIManager *uiManager, NSDictionary<NSNu
 CGFloat RCTJSONParseOnlyNumber(id json);
 
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/react-native/React/Views/RCTViewManager.m b/packages/react-native/React/Views/RCTViewManager.m
index b9bf09dd4e61..5f59c9b84bc0 100644
--- a/packages/react-native/React/Views/RCTViewManager.m
+++ b/packages/react-native/React/Views/RCTViewManager.m
@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 #import "RCTViewManager.h"
 
 #import "RCTAssert.h"
@@ -744,3 +746,5 @@ CGFloat RCTJSONParseOnlyNumber(id json)
 }
 
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.h b/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.h
index 23bc1be1cc44..a5a3275d10a0 100644
--- a/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.h
+++ b/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.h
@@ -7,8 +7,12 @@
 
 #import <React/RCTViewManager.h>
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 NS_ASSUME_NONNULL_BEGIN
 
 @interface InteropTestViewManager : RCTViewManager
 @end
 NS_ASSUME_NONNULL_END
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.m b/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.m
index ac76554a849c..1d4491ee8141 100644
--- a/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.m
+++ b/packages/rn-tester/NativeComponentExample/ios/RCTInteropTestViewManager.m
@@ -8,6 +8,8 @@
 #import "RCTInteropTestViewManager.h"
 #import "RCTInteropTestView.h"
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 @implementation InteropTestViewManager
 
 RCT_EXPORT_MODULE(InteropTestView)
@@ -18,3 +20,5 @@ - (UIView *)view
 }
 
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/rn-tester/NativeComponentExample/ios/RNTMyLegacyNativeViewManager.mm b/packages/rn-tester/NativeComponentExample/ios/RNTMyLegacyNativeViewManager.mm
index 35585daff495..2ef6c21118a8 100644
--- a/packages/rn-tester/NativeComponentExample/ios/RNTMyLegacyNativeViewManager.mm
+++ b/packages/rn-tester/NativeComponentExample/ios/RNTMyLegacyNativeViewManager.mm
@@ -12,6 +12,8 @@
 #import "RNTMyNativeViewComponentView.h"
 #import "UIView+ColorOverlays.h"
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 @interface RNTMyLegacyNativeViewManager : RCTViewManager
 
 @end
@@ -86,3 +88,5 @@ - (NSDictionary *)constantsToExport
   return @{@"PI" : @3.14};
 }
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP
diff --git a/packages/rn-tester/NativeComponentExample/ios/RNTMyNativeViewManager.mm b/packages/rn-tester/NativeComponentExample/ios/RNTMyNativeViewManager.mm
index 147da4612ff2..f9f7b33f82e0 100644
--- a/packages/rn-tester/NativeComponentExample/ios/RNTMyNativeViewManager.mm
+++ b/packages/rn-tester/NativeComponentExample/ios/RNTMyNativeViewManager.mm
@@ -10,6 +10,8 @@
 #import <React/RCTViewManager.h>
 #import "UIView+ColorOverlays.h"
 
+#ifndef RCT_REMOVE_LEGACY_COMPONENT_INTEROP
+
 @interface RNTMyNativeViewManager : RCTViewManager
 @end
 
@@ -42,3 +44,5 @@ - (UIView *)view
 }
 
 @end
+
+#endif // RCT_REMOVE_LEGACY_COMPONENT_INTEROP