From 36cb9315d4d75c1966b07776a438b5abec0eef38 Mon Sep 17 00:00:00 2001
From: Yevhenii <evgeny.kotyrlo@gmail.com>
Date: Wed, 14 Oct 2026 23:04:17 +0300
Subject: [PATCH] fix(codegen): skip third-party components whose class is not
 linked

Cherry-pick of react/react-native#59067 (acc0cca710), without its test
file change: this suite has no generateRCTThirdPartyComponents case.

The generated RCTThirdPartyComponentsProvider built its map from a
dictionary literal of NSClassFromString values, so a component whose
library the target does not link inserted nil and threw at launch.
react-native-macos runs codegen with -t ios, so a library's iOS
components reach a macOS target's provider whether or not the library
ships macOS classes.

The provider now maps each component name to its class name and skips a
class that is not found, as RCTModuleProvidersMM.template does for
modules.
---
 .../generate-artifacts-executor-test.js.snap  | 38 ++++++++++++++++---
 .../generateRCTThirdPartyComponents.js        |  2 +-
 ...RCTThirdPartyComponentsProviderMM.template | 16 +++++++-
 3 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/packages/react-native/scripts/codegen/__tests__/__snapshots__/generate-artifacts-executor-test.js.snap b/packages/react-native/scripts/codegen/__tests__/__snapshots__/generate-artifacts-executor-test.js.snap
index 8c76f937ae04..d0ff08d48ce0 100644
--- a/packages/react-native/scripts/codegen/__tests__/__snapshots__/generate-artifacts-executor-test.js.snap
+++ b/packages/react-native/scripts/codegen/__tests__/__snapshots__/generate-artifacts-executor-test.js.snap
@@ -328,10 +328,24 @@ exports[`execute test-app "ReactCodegen/RCTThirdPartyComponentsProvider.mm" shou
   static dispatch_once_t nativeComponentsToken;
 
   dispatch_once(&nativeComponentsToken, ^{
-    thirdPartyComponents = @{
-		@\\"TestAppComponent\\": NSClassFromString(@\\"RCTTestAppComponent\\"), // test-app
-		@\\"TestLibraryComponent\\": NSClassFromString(@\\"RCTTestLibraryComponent\\"), // test-library
+    NSDictionary<NSString *, NSString *> * componentMapping = @{
+		@\\"TestAppComponent\\": @\\"RCTTestAppComponent\\", // test-app
+		@\\"TestLibraryComponent\\": @\\"RCTTestLibraryComponent\\", // test-library
     };
+
+    NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithCapacity:componentMapping.count];
+
+    for (NSString *key in componentMapping) {
+      // Nil for a library this target does not link (an app extension, macOS).
+      Class klass = NSClassFromString(componentMapping[key]);
+      if (!klass) {
+        continue;
+      }
+
+      [dict setObject:klass forKey:key];
+    }
+
+    thirdPartyComponents = dict;
   });
 
   return thirdPartyComponents;
@@ -817,9 +831,23 @@ exports[`execute test-app-legacy "ReactCodegen/RCTThirdPartyComponentsProvider.m
   static dispatch_once_t nativeComponentsToken;
 
   dispatch_once(&nativeComponentsToken, ^{
-    thirdPartyComponents = @{
-		@\\"TestAppDeprecatedComponent\\": NSClassFromString(@\\"RCTTestAppDeprecatedComponentClass\\"), // test-app-legacy
+    NSDictionary<NSString *, NSString *> * componentMapping = @{
+		@\\"TestAppDeprecatedComponent\\": @\\"RCTTestAppDeprecatedComponentClass\\", // test-app-legacy
     };
+
+    NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithCapacity:componentMapping.count];
+
+    for (NSString *key in componentMapping) {
+      // Nil for a library this target does not link (an app extension, macOS).
+      Class klass = NSClassFromString(componentMapping[key]);
+      if (!klass) {
+        continue;
+      }
+
+      [dict setObject:klass forKey:key];
+    }
+
+    thirdPartyComponents = dict;
   });
 
   return thirdPartyComponents;
diff --git a/packages/react-native/scripts/codegen/generate-artifacts-executor/generateRCTThirdPartyComponents.js b/packages/react-native/scripts/codegen/generate-artifacts-executor/generateRCTThirdPartyComponents.js
index d54bd708c7b7..3b926b17a0a9 100644
--- a/packages/react-native/scripts/codegen/generate-artifacts-executor/generateRCTThirdPartyComponents.js
+++ b/packages/react-native/scripts/codegen/generate-artifacts-executor/generateRCTThirdPartyComponents.js
@@ -138,7 +138,7 @@ function generateRCTThirdPartyComponents(
     .flatMap(library => {
       const components = componentsInLibraries[library];
       return components.map(({componentName, className}) => {
-        return `\t\t@"${componentName}": NSClassFromString(@"${className}"), // ${library}`;
+        return `\t\t@"${componentName}": @"${className}", // ${library}`;
       });
     })
     .join('\n');
diff --git a/packages/react-native/scripts/codegen/templates/RCTThirdPartyComponentsProviderMM.template b/packages/react-native/scripts/codegen/templates/RCTThirdPartyComponentsProviderMM.template
index 4ce510709e33..6c50d6d9c98c 100644
--- a/packages/react-native/scripts/codegen/templates/RCTThirdPartyComponentsProviderMM.template
+++ b/packages/react-native/scripts/codegen/templates/RCTThirdPartyComponentsProviderMM.template
@@ -19,9 +19,23 @@
   static dispatch_once_t nativeComponentsToken;
 
   dispatch_once(&nativeComponentsToken, ^{
-    thirdPartyComponents = @{
+    NSDictionary<NSString *, NSString *> * componentMapping = @{
 {thirdPartyComponentsMapping}
     };
+
+    NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithCapacity:componentMapping.count];
+
+    for (NSString *key in componentMapping) {
+      // Nil for a library this target does not link (an app extension, macOS).
+      Class klass = NSClassFromString(componentMapping[key]);
+      if (!klass) {
+        continue;
+      }
+
+      [dict setObject:klass forKey:key];
+    }
+
+    thirdPartyComponents = dict;
   });
 
   return thirdPartyComponents;