Improvements

packages/react-native-reanimated/src/createAnimatedComponent/createAnimatedComponent.tsx

@@ -11,7 +11,7 @@ import { Platform } from 'react-native';
 import '../layoutReanimation/animationsManager';
 import invariant from 'invariant';
 import { adaptViewConfig } from '../ConfigHelper';
-import { findHostInstance } from '../platform-specific/RNRenderer';
+import { findHostInstance } from '../platform-specific/findHostInstance';
 import { enableLayoutAnimations } from '../core';
 import { SharedTransition } from '../layoutReanimation';
 import { LayoutAnimationType } from '../commonTypes';
@@ -497,7 +497,7 @@ export function createAnimatedComponent(
         >,
       setLocalRef: (ref) => {
         if (!ref) {
-          // component is unmounted
+          // component has been unmounted
           return;
         }
         if (ref !== this._componentRef) {

packages/react-native-reanimated/src/fabricUtils.ts

@@ -2,15 +2,18 @@
 /* eslint-disable */
 
 import type { ShadowNodeWrapper } from './commonTypes';
-import { findHostInstance } from './platform-specific/RNRenderer';
+import {
+  findHostInstance,
+  HostInstance,
+} from './platform-specific/findHostInstance';
 
 let getInternalInstanceHandleFromPublicInstance: (ref: unknown) => {
   stateNode: { node: unknown };
 };
 
 export function getShadowNodeWrapperFromRef(
   ref: React.Component,
-  hostInstance?: unknown
+  hostInstance?: HostInstance
 ): ShadowNodeWrapper {
   if (getInternalInstanceHandleFromPublicInstance === undefined) {
     try {

packages/react-native-reanimated/src/platform-specific/findHostInstance.ts

@@ -0,0 +1,75 @@
+/* eslint-disable camelcase */
+// eslint-disable-next-line @typescript-eslint/ban-ts-comment
+'use strict';
+
+import type { IAnimatedComponentInternal } from '../createAnimatedComponent/commonTypes';
+import { ReanimatedError } from '../errors';
+import { isFabric } from '../PlatformChecker';
+
+export type HostInstance = {
+  // Fabric fields
+  __internalInstanceHandle?: Record<string, unknown>;
+  __nativeTag?: number;
+  _viewConfig?: Record<string, unknown>;
+  // Paper fields
+  _nativeTag?: number;
+  viewConfig?: Record<string, unknown>;
+};
+
+function findHostInstanceFastPath(maybeNativeRef: HostInstance) {
+  if (
+    maybeNativeRef.__internalInstanceHandle &&
+    maybeNativeRef.__nativeTag &&
+    maybeNativeRef._viewConfig
+  ) {
+    // This is a native ref to a Fabric component
+    return maybeNativeRef;
+  }
+  if (maybeNativeRef._nativeTag && maybeNativeRef.viewConfig) {
+    // This is a native ref to a Paper component
+    return maybeNativeRef;
+  }
+  // That means it’s a ref to a non-native component, and it’s necessary
+  // to call `findHostInstance_DEPRECATED` on them.
+  return undefined;
+}
+
+function resolveFindHostInstance_DEPRECATED() {
+  if (findHostInstance_DEPRECATED !== undefined) {
+    return;
+  }
+  if (isFabric()) {
+    try {
+      findHostInstance_DEPRECATED =
+        require('react-native/Libraries/Renderer/shims/ReactFabric').findHostInstance_DEPRECATED;
+    } catch (e) {
+      throw new ReanimatedError(
+        'Failed to resolve findHostInstance_DEPRECATED'
+      );
+    }
+  } else {
+    findHostInstance_DEPRECATED =
+      require('react-native/Libraries/Renderer/shims/ReactNative').findHostInstance_DEPRECATED;
+  }
+}
+
+let findHostInstance_DEPRECATED: (ref: unknown) => HostInstance;
+export function findHostInstance(
+  component: IAnimatedComponentInternal | React.Component
+): HostInstance {
+  // Fast path for native refs
+  const hostInstance = findHostInstanceFastPath(
+    (component as IAnimatedComponentInternal)._componentRef as HostInstance
+  );
+  if (hostInstance !== undefined) {
+    return hostInstance;
+  }
+
+  resolveFindHostInstance_DEPRECATED();
+  // Fabric implementation of findHostInstance_DEPRECATED doesn't accept a ref as an argument
+  return findHostInstance_DEPRECATED(
+    isFabric()
+      ? component
+      : (component as IAnimatedComponentInternal)._componentRef
+  );
+}

packages/react-native-reanimated/src/platform-specific/findHostInstance.web.ts

@@ -0,0 +1,3 @@
+'use strict';
+
+export function findHostInstance(_component: any): void {}