From fdb77ae92444fa68128265254a11b3cd9950c33b Mon Sep 17 00:00:00 2001
From: Pieter De Baets <pieterdb@meta.com>
Date: Mon, 26 Aug 2024 09:38:00 -0700
Subject: [PATCH] Reset animatedView when detaching AnimatedProps (#46205)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/46205

When React.Activity unmounts and remounts effects, we fail to re-attach the native view to the NativeAnimated nodes, which causes animations to stop working.

Changelog: [Internal]

Reviewed By: sammy-SC, bvanderhoof

Differential Revision: D61662164

fbshipit-source-id: 8e86502f7258beba02d5e60b31864974d7288af5
---
 .../Animated/__tests__/AnimatedNative-test.js | 55 ++++++++++++++++++-
 .../Libraries/Animated/nodes/AnimatedProps.js |  2 +
 2 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/packages/react-native/Libraries/Animated/__tests__/AnimatedNative-test.js b/packages/react-native/Libraries/Animated/__tests__/AnimatedNative-test.js
index 4d2f2ce3e32..6e5c9b302b8 100644
--- a/packages/react-native/Libraries/Animated/__tests__/AnimatedNative-test.js
+++ b/packages/react-native/Libraries/Animated/__tests__/AnimatedNative-test.js
@@ -25,6 +25,7 @@ jest
 
 import {format} from 'node:util';
 import * as React from 'react';
+import {createRef} from 'react';
 
 const {create, unmount, update} = require('../../../jest/renderer');
 const Animated = require('../Animated').default;
@@ -1265,7 +1266,7 @@ describe('Native Animated', () => {
   });
 
   describe('Animated Components', () => {
-    it('Should restore default values on prop updates only', async () => {
+    it('should restore default values on prop updates only', async () => {
       const opacity = new Animated.Value(0);
       opacity.__makeNative();
 
@@ -1283,5 +1284,57 @@ describe('Native Animated', () => {
         1,
       );
     });
+
+    it('connects the native view on mount and disconnects on unmount', async () => {
+      const opacity = new Animated.Value(0, {useNativeDriver: true});
+
+      const root = await create(<Animated.View style={{opacity}} />);
+
+      // AnimatedProps > AnimatedStyle > opacity AnimatedValue
+      const propsTag = opacity
+        .__getChildren()[0]
+        .__getChildren()[0]
+        .__getNativeTag();
+      expect(NativeAnimatedModule.connectAnimatedNodeToView).toBeCalledWith(
+        propsTag,
+        1,
+      );
+
+      await unmount(root);
+      expect(
+        NativeAnimatedModule.disconnectAnimatedNodeFromView,
+      ).toBeCalledWith(propsTag, 1);
+    });
+
+    it('reconnects the native view when the component is remounted', async () => {
+      const opacity = new Animated.Value(0, {useNativeDriver: true});
+      const ref = createRef();
+      await create(<Animated.View ref={ref} style={{opacity}} />);
+
+      // AnimatedProps > AnimatedStyle > opacity AnimatedValue
+      const propsNode = opacity.__getChildren()[0].__getChildren()[0];
+      let propsTag = propsNode.__nativeTag;
+      expect(NativeAnimatedModule.connectAnimatedNodeToView).nthCalledWith(
+        1,
+        propsTag,
+        1,
+      );
+
+      // Simulate what happens when React.Activity unmounts and remounts
+      propsNode.__detach();
+      expect(
+        NativeAnimatedModule.disconnectAnimatedNodeFromView,
+      ).toBeCalledWith(propsTag, 1);
+
+      propsNode.__attach();
+      propsNode.setNativeView(ref.current);
+
+      propsTag = propsNode.__nativeTag;
+      expect(NativeAnimatedModule.connectAnimatedNodeToView).nthCalledWith(
+        2,
+        propsTag,
+        1,
+      );
+    });
   });
 });
diff --git a/packages/react-native/Libraries/Animated/nodes/AnimatedProps.js b/packages/react-native/Libraries/Animated/nodes/AnimatedProps.js
index d6c3462590b..d8a048e82eb 100644
--- a/packages/react-native/Libraries/Animated/nodes/AnimatedProps.js
+++ b/packages/react-native/Libraries/Animated/nodes/AnimatedProps.js
@@ -88,6 +88,8 @@ export default class AnimatedProps extends AnimatedNode {
     if (this.__isNative && this._animatedView) {
       this.__disconnectAnimatedView();
     }
+    this._animatedView = null;
+
     for (const key in this._props) {
       const value = this._props[key];
       if (value instanceof AnimatedNode) {