More test cases - custom layout transitions (#6458)

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## Summary

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## Test plan

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Author: Latropos

apps/common-app/src/examples/RuntimeTests/RuntimeTestsExample.tsx

@@ -71,9 +71,10 @@ export default function RuntimeTestsExample() {
             describe('Compare layout transitions with **constant view size** with snapshots', () => {
               require('./tests/layoutAnimations/layout/predefinedLayoutPosition.test');
             });
-            describe('Compare Test layout transitions including view **size changes** with snapshots', () => {
+            describe('Compare predefined layout transitions including view **size changes** with snapshots', () => {
               require('./tests/layoutAnimations/layout/positionAndSize.test');
             });
+            require('./tests/layoutAnimations/layout/custom.test');
           },
         },
         {

apps/common-app/src/examples/RuntimeTests/tests/layoutAnimations/layout/TestComponents.tsx

@@ -1,7 +1,18 @@
 import React, { useState, useEffect } from 'react';
 import { View, StyleSheet } from 'react-native';
 import Animated from 'react-native-reanimated';
-import { useTestRef } from '../../../ReJest/RuntimeTestsApi';
+import {
+  clearRenderOutput,
+  getTestComponent,
+  mockAnimationTimer,
+  mockWindowDimensions,
+  recordAnimationUpdates,
+  render,
+  unmockAnimationTimer,
+  unmockWindowDimensions,
+  useTestRef,
+  waitForAnimationUpdates,
+} from '../../../ReJest/RuntimeTestsApi';
 
 export const TRANSITION_REF = 'TRANSITION_REF';
 export enum Direction {
@@ -13,6 +24,32 @@ export enum Direction {
   LEFT_UP = 'LEFT_UP',
 }
 
+export async function getSnapshotUpdates(
+  layout: any,
+  direction: Direction,
+  snapshotLength: number,
+  changeSize?: boolean,
+) {
+  await mockAnimationTimer();
+  await mockWindowDimensions();
+
+  const updatesContainer = await recordAnimationUpdates();
+  if (direction === Direction.UP || direction === Direction.DOWN) {
+    await render(<TransitionUpOrDown layout={layout} direction={direction} changeSize={!!changeSize} />);
+  } else {
+    await render(<TransitionLeftOrRight layout={layout} direction={direction} changeSize={!!changeSize} />);
+  }
+  await waitForAnimationUpdates(snapshotLength);
+  const component = getTestComponent(TRANSITION_REF);
+  const updates = updatesContainer.getUpdates(component);
+
+  await unmockAnimationTimer();
+  await unmockWindowDimensions();
+  await clearRenderOutput();
+
+  return updates;
+}
+
 export const TransitionUpOrDown = ({
   layout,
   direction,