gate new code

Author: kassens

packages/react-native-renderer/src/__tests__/ReactFabric-test.internal.js

@@ -273,6 +273,7 @@ describe('ReactFabric', () => {
     expect(nativeFabricUIManager.completeRoot).toBeCalled();
   });
 
+  // @gate enablePersistedModeClonedFlag
   it('should not clone nodes when layout effects are used', async () => {
     const View = createReactNativeComponentClass('RCTView', () => ({
       validAttributes: {foo: true},

packages/react-reconciler/src/ReactFiberCommitWork.js

@@ -42,6 +42,7 @@ import type {
 import {
   alwaysThrottleDisappearingFallbacks,
   enableCreateEventHandleAPI,
+  enablePersistedModeClonedFlag,
   enableProfilerTimer,
   enableProfilerCommitHooks,
   enableProfilerNestedUpdatePhase,
@@ -2508,7 +2509,10 @@ function recursivelyTraverseMutationEffects(
   }
 
   const prevDebugFiber = getCurrentDebugFiberInDEV();
-  if (parentFiber.subtreeFlags & (MutationMask | Cloned)) {
+  if (
+    parentFiber.subtreeFlags &
+    (enablePersistedModeClonedFlag ? MutationMask | Cloned : MutationMask)
+  ) {
     let child = parentFiber.child;
     while (child !== null) {
       setCurrentDebugFiberInDEV(child);

packages/react-reconciler/src/ReactFiberCompleteWork.js

@@ -35,6 +35,7 @@ import {
   enableLegacyHidden,
   enableSuspenseCallback,
   enableScopeAPI,
+  enablePersistedModeClonedFlag,
   enableProfilerTimer,
   enableCache,
   enableTransitionTracing,
@@ -83,6 +84,7 @@ import {
   Snapshot,
   ChildDeletion,
   StaticMask,
+  MutationMask,
   Passive,
   ForceClientRender,
   MaySuspendCommit,
@@ -187,7 +189,7 @@ function markUpdate(workInProgress: Fiber) {
  * it received an update that requires a clone of the tree above.
  */
 function markCloned(workInProgress: Fiber) {
-  if (supportsPersistence) {
+  if (supportsPersistence && enablePersistedModeClonedFlag) {
     workInProgress.flags |= Cloned;
   }
 }
@@ -209,9 +211,12 @@ function doesRequireClone(current: null | Fiber, completedWork: Fiber) {
   // then we only have to check the `completedWork.subtreeFlags`.
   let child = completedWork.child;
   while (child !== null) {
+    const checkedFlags = enablePersistedModeClonedFlag
+      ? Cloned | Visibility | Placement
+      : MutationMask;
     if (
-      (child.flags & (Cloned | Visibility | Placement)) !== NoFlags ||
-      (child.subtreeFlags & (Cloned | Visibility | Placement)) !== NoFlags
+      (child.flags & checkedFlags) !== NoFlags ||
+      (child.subtreeFlags & checkedFlags) !== NoFlags
     ) {
       return true;
     }
@@ -498,7 +503,14 @@ function updateHostComponent(
       markUpdate(workInProgress);
     }
     workInProgress.stateNode = newInstance;
-    if (requiresClone && !passChildrenWhenCloningPersistedNodes) {
+    if (!requiresClone) {
+      if (!enablePersistedModeClonedFlag) {
+        // If there are no other effects in this tree, we need to flag this node as having one.
+        // Even though we're not going to use it for anything.
+        // Otherwise parents won't know that there are new children to propagate upwards.
+        markUpdate(workInProgress);
+      }
+    } else if (!passChildrenWhenCloningPersistedNodes) {
       // If children have changed, we have to add them all to the set.
       appendAllChildren(
         newInstance,
@@ -665,6 +677,11 @@ function updateHostText(
         currentHostContext,
         workInProgress,
       );
+      if (!enablePersistedModeClonedFlag) {
+        // We'll have to mark it as having an effect, even though we won't use the effect for anything.
+        // This lets the parents know that at least one of their children has changed.
+        markUpdate(workInProgress);
+      }
     } else {
       workInProgress.stateNode = current.stateNode;
     }