stub rn codegen native component on web

src/lib/web-shims/codegenNativeComponent.js

@@ -0,0 +1,17 @@
+/*
+ * Web stub for `react-native/Libraries/Utilities/codegenNativeComponent`.
+ *
+ * Deep `react-native/*` imports bypass the `react-native$ -> react-native-web`
+ * alias and drag RN core into the web bundle, where its platform-extension
+ * modules (e.g. Libraries/Utilities/Platform.js) resolve to themselves and
+ * throw a TDZ error at startup. Packages that import codegen specs
+ * unconditionally (react-native-uitextview) guard the native component behind
+ * a `Platform.OS === 'ios'` check, so nothing ever renders this on web.
+ */
+module.exports = function codegenNativeComponent(componentName) {
+  return function UnimplementedNativeComponent() {
+    throw new Error(
+      `Native component "${componentName}" was rendered on web. It has no web implementation.`,
+    )
+  }
+}

webpack.config.js

@@ -62,6 +62,16 @@ module.exports = async function (env, argv) {
   }
   config = withAlias(config, {
     'react-native$': 'react-native-web',
+    /*
+     * Codegen specs import this via a deep `react-native/*` path, which skips
+     * the exact-match alias above and pulls RN core into the web bundle. RN
+     * core's platform-extension modules have no `.web` variant, so they
+     * resolve to themselves and blow up with a TDZ error on startup.
+     */
+    'react-native/Libraries/Utilities/codegenNativeComponent$': path.join(
+      __dirname,
+      'src/lib/web-shims/codegenNativeComponent.js',
+    ),
     'react-native-webview': 'react-native-web-webview',
     'react-native-gesture-handler': false, // RNGH should not be used on web, so let's cause a build error if it sneaks in
     '@sentry-internal/replay': false, // not used, ~300kb of dead weight