fix: replace RCTUISecureTextField #include hack with proper subclass (#2895)

## Summary
- Replaces the fragile preprocessor `#include .mm` trick in
`RCTUISecureTextField` with proper OOP inheritance
- `RCTUISecureTextField` now subclasses `RCTUITextField` directly and
overrides `+cellClass` to return `RCTUISecureTextFieldCell :
NSSecureTextFieldCell`
- Removes all `RCT_SUBCLASS_SECURETEXTFIELD` preprocessor conditionals
from `RCTUITextField.h/.mm`
- Updates `isKindOfClass:[NSSecureTextField class]` checks to
`[RCTUISecureTextField class]` in both Paper and Fabric code paths

## Motivation
The old approach `#include`d the entire 734-line `RCTUITextField.mm`
with a `#define` to swap class/superclass names — a preprocessor trick
to work around a diamond inheritance problem. This caused
duplicate-symbol linker errors on non-macOS SPM builds and was fragile
and confusing.

Since `NSSecureTextField`'s masking behavior lives entirely in
`NSSecureTextFieldCell`, the proper fix is to subclass `RCTUITextField`
and override just the cell class (~50 lines of duplicated cell code vs.
734 lines recompiled via include).

## Test plan
- [ ] macOS build succeeds (RCTUISecureTextField inherits all behavior
from RCTUITextField)
- [ ] Secure text fields still mask input on macOS (masking comes from
NSSecureTextFieldCell)
- [ ] iOS/visionOS SPM builds pass without duplicate symbols or excludes
- [ ] No regressions in text input behavior

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: Saadnajmi

packages/react-native/Libraries/Text/TextInput/RCTBackedTextInputDelegateAdapter.mm

@@ -8,7 +8,7 @@
 #import <React/RCTBackedTextInputDelegateAdapter.h>
 #import "RCTBackedTextInputViewProtocol.h" // [macOS
 #import "RCTBackedTextInputDelegate.h"
-#import "../RCTTextUIKit.h" // macOS]
+#import <React/RCTTextUIKit.h> // macOS]
 
 #pragma mark - RCTBackedTextFieldDelegateAdapter (for UITextField)
 

packages/react-native/Libraries/Text/TextInput/RCTBaseTextInputView.mm

@@ -21,8 +21,11 @@
 #import <React/RCTTextAttributes.h>
 #import <React/RCTTextSelection.h>
 #import <React/RCTUITextView.h> // [macOS]
-#import "../RCTTextUIKit.h" // [macOS]
+#import <React/RCTTextUIKit.h> // [macOS]
 #import <React/RCTHandledKey.h> // [macOS]
+#if TARGET_OS_OSX // [macOS
+#import <React/RCTUISecureTextField.h>
+#endif // macOS]
 
 /** Native iOS text field bottom keyboard offset amount */
 static const CGFloat kSingleLineKeyboardBottomOffset = 15.0;
@@ -194,7 +197,7 @@ - (BOOL)textOf:(NSAttributedString *)newText equals:(NSAttributedString *)oldTex
   BOOL shouldFallbackToBareTextComparison =
     // There are multiple Korean input sources (2-Set, 3-Set, etc). Check substring instead instead
     [[[self.backedTextInputView inputContext] selectedKeyboardInputSource] containsString:@"com.apple.inputmethod.Korean"] ||
-    [self.backedTextInputView hasMarkedText] || [self.backedTextInputView isKindOfClass:[NSSecureTextField class]] ||
+    [self.backedTextInputView hasMarkedText] || [self.backedTextInputView isKindOfClass:[RCTUISecureTextField class]] ||
 #endif // macOS]
       fontHasBeenUpdatedBySystem;
 

packages/react-native/Libraries/Text/TextInput/Singleline/RCTUITextField.h

@@ -20,11 +20,7 @@ NS_ASSUME_NONNULL_BEGIN
 #if !TARGET_OS_OSX // [macOS]
 @interface RCTUITextField : UITextField <RCTBackedTextInputViewProtocol>
 #else // [macOS
-#if RCT_SUBCLASS_SECURETEXTFIELD
-@interface RCTUISecureTextField : NSSecureTextField <RCTBackedTextInputViewProtocol>
-#else
 @interface RCTUITextField : NSTextField <RCTBackedTextInputViewProtocol>
-#endif // RCT_SUBCLASS_SECURETEXTFIELD
 #endif // macOS]
 
 

packages/react-native/Libraries/Text/TextInput/Singleline/RCTUITextField.mm

@@ -17,12 +17,7 @@
 
 #if TARGET_OS_OSX // [macOS
 
-#if RCT_SUBCLASS_SECURETEXTFIELD
-#define RCTUITextFieldCell RCTUISecureTextFieldCell
-@interface RCTUISecureTextFieldCell : NSSecureTextFieldCell
-#else
 @interface RCTUITextFieldCell : NSTextFieldCell
-#endif
 
 @property (nonatomic, assign) UIEdgeInsets textContainerInset;
 @property (nonatomic, getter=isAutomaticTextReplacementEnabled) BOOL automaticTextReplacementEnabled;
@@ -36,11 +31,6 @@ @interface RCTUITextFieldCell : NSTextFieldCell
 
 @implementation RCTUITextFieldCell
 
-- (void)setTextContainerInset:(UIEdgeInsets)textContainerInset
-{
-  _textContainerInset = textContainerInset;
-}
-
 - (NSRect)titleRectForBounds:(NSRect)rect
 {
   return UIEdgeInsetsInsetRect([super titleRectForBounds:rect], self.textContainerInset);
@@ -58,12 +48,9 @@ - (void)selectWithFrame:(NSRect)rect inView:(NSView *)controlView editor:(NSText
 
 - (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
 {
-  if (self.drawsBackground) {
-    if (self.backgroundColor && self.backgroundColor.alphaComponent > 0) {
-
-      [self.backgroundColor set];
-      NSRectFill(cellFrame);
-    }
+  if (self.drawsBackground && self.backgroundColor && self.backgroundColor.alphaComponent > 0) {
+    [self.backgroundColor set];
+    NSRectFill(cellFrame);
   }
 
   [super drawInteriorWithFrame:[self titleRectForBounds:cellFrame] inView:controlView];
@@ -86,11 +73,7 @@ - (NSText *)setUpFieldEditorAttributes:(NSText *)textObj
 @end
 #endif // macOS]
 
-#ifdef RCT_SUBCLASS_SECURETEXTFIELD
-@implementation RCTUISecureTextField {
-#else
 @implementation RCTUITextField {
-#endif
   RCTBackedTextFieldDelegateAdapter *_textInputDelegateAdapter;
   NSDictionary<NSAttributedStringKey, id> *_defaultTextAttributes;
 #if !TARGET_OS_OSX // [macOS]

packages/react-native/Libraries/Text/TextInput/Singleline/macOS/RCTUISecureTextField.h

@@ -8,8 +8,10 @@
 // [macOS]
 
 #if TARGET_OS_OSX
-#define RCT_SUBCLASS_SECURETEXTFIELD 1
-#endif
 
-#include <React/RCTUITextField.h>
+#import <React/RCTUITextField.h>
+
+@interface RCTUISecureTextField : RCTUITextField
+@end
 
+#endif

packages/react-native/Libraries/Text/TextInput/Singleline/macOS/RCTUISecureTextField.m

@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+// [macOS]
+
+#if TARGET_OS_OSX
+
+#import <React/RCTUISecureTextField.h>
+#import <React/RCTUIKit.h>
+
+#pragma mark - RCTUISecureTextFieldCell
+
+@interface RCTUISecureTextFieldCell : NSSecureTextFieldCell
+
+@property (nonatomic, assign) UIEdgeInsets textContainerInset;
+@property (nonatomic, getter=isAutomaticTextReplacementEnabled) BOOL automaticTextReplacementEnabled;
+@property (nonatomic, getter=isAutomaticSpellingCorrectionEnabled) BOOL automaticSpellingCorrectionEnabled;
+@property (nonatomic, getter=isContinuousSpellCheckingEnabled) BOOL continuousSpellCheckingEnabled;
+@property (nonatomic, getter=isGrammarCheckingEnabled) BOOL grammarCheckingEnabled;
+@property (nonatomic, strong, nullable) RCTPlatformColor *selectionColor;
+@property (nonatomic, strong, nullable) RCTPlatformColor *insertionPointColor;
+
+@end
+
+@implementation RCTUISecureTextFieldCell
+
+- (NSRect)titleRectForBounds:(NSRect)rect
+{
+  return UIEdgeInsetsInsetRect([super titleRectForBounds:rect], self.textContainerInset);
+}
+
+- (void)editWithFrame:(NSRect)rect inView:(NSView *)controlView editor:(NSText *)textObj delegate:(id)delegate event:(NSEvent *)event
+{
+  [super editWithFrame:[self titleRectForBounds:rect] inView:controlView editor:textObj delegate:delegate event:event];
+}
+
+- (void)selectWithFrame:(NSRect)rect inView:(NSView *)controlView editor:(NSText *)textObj delegate:(id)delegate start:(NSInteger)selStart length:(NSInteger)selLength
+{
+  [super selectWithFrame:[self titleRectForBounds:rect] inView:controlView editor:textObj delegate:delegate start:selStart length:selLength];
+}
+
+- (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView *)controlView
+{
+  if (self.drawsBackground && self.backgroundColor && self.backgroundColor.alphaComponent > 0) {
+    [self.backgroundColor set];
+    NSRectFill(cellFrame);
+  }
+
+  [super drawInteriorWithFrame:[self titleRectForBounds:cellFrame] inView:controlView];
+}
+
+- (NSText *)setUpFieldEditorAttributes:(NSText *)textObj
+{
+  NSTextView *fieldEditor = (NSTextView *)[super setUpFieldEditorAttributes:textObj];
+  fieldEditor.automaticSpellingCorrectionEnabled = self.isAutomaticSpellingCorrectionEnabled;
+  fieldEditor.automaticTextReplacementEnabled = self.isAutomaticTextReplacementEnabled;
+  fieldEditor.continuousSpellCheckingEnabled = self.isContinuousSpellCheckingEnabled;
+  fieldEditor.grammarCheckingEnabled = self.isGrammarCheckingEnabled;
+  NSMutableDictionary *selectTextAttributes = fieldEditor.selectedTextAttributes.mutableCopy;
+  selectTextAttributes[NSBackgroundColorAttributeName] = self.selectionColor ?: [NSColor selectedControlColor];
+  fieldEditor.selectedTextAttributes = selectTextAttributes;
+  fieldEditor.insertionPointColor = self.insertionPointColor ?: [NSColor textColor];
+  return fieldEditor;
+}
+
+@end
+
+#pragma mark - RCTUISecureTextField
+
+@implementation RCTUISecureTextField
+
++ (Class)cellClass
+{
+  return RCTUISecureTextFieldCell.class;
+}
+
+@end
+
+#endif // TARGET_OS_OSX

packages/react-native/Libraries/Text/TextInput/Singleline/macOS/RCTUISecureTextField.mm

@@ -1219,7 +1219,7 @@ - (BOOL)_textOf:(NSAttributedString *)newText equals:(NSAttributedString *)oldTe
   // There are multiple Korean input sources (2-Set, 3-Set, etc). Check substring instead instead
   [[[_backedTextInputView inputContext] selectedKeyboardInputSource] containsString:@"com.apple.inputmethod.Korean"] ||
   [_backedTextInputView hasMarkedText] ||
-  [_backedTextInputView isKindOfClass:[NSSecureTextField class]] ||
+  [_backedTextInputView isKindOfClass:[RCTUISecureTextField class]] ||
 #endif // macOS]
   fontHasBeenUpdatedBySystem;