Use recursion to traverse during layout phase

This converts the layout phase to iterate over its effects
recursively instead of iteratively. This makes it easier to track 
contextual information, like whether a fiber is inside a hidden tree.

We already made this change for the mutation phase. See 481dece for
more context.

Author: acdlite

packages/react-reconciler/src/ReactFiberCommitWork.new.js

@@ -716,6 +716,11 @@ function commitLayoutEffectOnFiber(
     case FunctionComponent:
     case ForwardRef:
     case SimpleMemoComponent: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (flags & Update) {
         if (!offscreenSubtreeWasHidden) {
           // At this point layout effects have already been destroyed (during mutation phase).
@@ -752,6 +757,11 @@ function commitLayoutEffectOnFiber(
       break;
     }
     case ClassComponent: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (flags & Update) {
         if (!offscreenSubtreeWasHidden) {
           const instance = finishedWork.stateNode;
@@ -946,6 +956,11 @@ function commitLayoutEffectOnFiber(
       break;
     }
     case HostRoot: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (flags & Callback) {
         // TODO: I think this is now always non-null by the time it reaches the
         // commit phase. Consider removing the type check.
@@ -974,6 +989,11 @@ function commitLayoutEffectOnFiber(
       break;
     }
     case HostComponent: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (flags & Update) {
         const instance: Instance = finishedWork.stateNode;
 
@@ -1003,15 +1023,12 @@ function commitLayoutEffectOnFiber(
       }
       break;
     }
-    case HostText: {
-      // We have no life-cycles associated with text.
-      break;
-    }
-    case HostPortal: {
-      // We have no life-cycles associated with portals.
-      break;
-    }
     case Profiler: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (enableProfilerTimer) {
         if (flags & Update) {
           try {
@@ -1078,6 +1095,11 @@ function commitLayoutEffectOnFiber(
       break;
     }
     case SuspenseComponent: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
+      );
       if (flags & Update) {
         try {
           commitSuspenseHydrationCallbacks(finishedRoot, finishedWork);
@@ -1087,20 +1109,58 @@ function commitLayoutEffectOnFiber(
       }
       break;
     }
-    case SuspenseListComponent:
-    case IncompleteClassComponent:
-    case ScopeComponent:
-    case OffscreenComponent:
-    case LegacyHiddenComponent:
-    case TracingMarkerComponent: {
+    case OffscreenComponent: {
+      const isModernRoot = (finishedWork.mode & ConcurrentMode) !== NoMode;
+      if (isModernRoot) {
+        const isHidden = finishedWork.memoizedState !== null;
+        const newOffscreenSubtreeIsHidden =
+          isHidden || offscreenSubtreeIsHidden;
+        if (newOffscreenSubtreeIsHidden) {
+          // The Offscreen tree is hidden. Skip over its layout effects.
+        } else {
+          // The Offscreen tree is visible.
+
+          const wasHidden = current !== null && current.memoizedState !== null;
+          const newOffscreenSubtreeWasHidden =
+            wasHidden || offscreenSubtreeWasHidden;
+          const prevOffscreenSubtreeIsHidden = offscreenSubtreeIsHidden;
+          const prevOffscreenSubtreeWasHidden = offscreenSubtreeWasHidden;
+          offscreenSubtreeIsHidden = newOffscreenSubtreeIsHidden;
+          offscreenSubtreeWasHidden = newOffscreenSubtreeWasHidden;
+
+          if (offscreenSubtreeWasHidden && !prevOffscreenSubtreeWasHidden) {
+            // This is the root of a reappearing boundary. Turn its layout
+            // effects back on.
+            // TODO: Convert this to use recursion
+            nextEffect = finishedWork;
+            reappearLayoutEffects_begin(finishedWork);
+          }
+
+          recursivelyTraverseLayoutEffects(
+            finishedRoot,
+            finishedWork,
+            committedLanes,
+          );
+          offscreenSubtreeIsHidden = prevOffscreenSubtreeIsHidden;
+          offscreenSubtreeWasHidden = prevOffscreenSubtreeWasHidden;
+        }
+      } else {
+        recursivelyTraverseLayoutEffects(
+          finishedRoot,
+          finishedWork,
+          committedLanes,
+        );
+      }
       break;
     }
-
-    default:
-      throw new Error(
-        'This unit of work tag should not have side-effects. This error is ' +
-          'likely caused by a bug in React. Please file an issue.',
+    default: {
+      recursivelyTraverseLayoutEffects(
+        finishedRoot,
+        finishedWork,
+        committedLanes,
       );
+      break;
+    }
   }
 }
 
@@ -2591,112 +2651,30 @@ export function commitLayoutEffects(
 ): void {
   inProgressLanes = committedLanes;
   inProgressRoot = root;
-  nextEffect = finishedWork;
 
-  commitLayoutEffects_begin(finishedWork, root, committedLanes);
+  const current = finishedWork.alternate;
+  commitLayoutEffectOnFiber(root, current, finishedWork, committedLanes);
 
   inProgressLanes = null;
   inProgressRoot = null;
 }
 
-function commitLayoutEffects_begin(
-  subtreeRoot: Fiber,
+function recursivelyTraverseLayoutEffects(
   root: FiberRoot,
-  committedLanes: Lanes,
-) {
-  // Suspense layout effects semantics don't change for legacy roots.
-  const isModernRoot = (subtreeRoot.mode & ConcurrentMode) !== NoMode;
-
-  while (nextEffect !== null) {
-    const fiber = nextEffect;
-    const firstChild = fiber.child;
-
-    if (fiber.tag === OffscreenComponent && isModernRoot) {
-      // Keep track of the current Offscreen stack's state.
-      const isHidden = fiber.memoizedState !== null;
-      const newOffscreenSubtreeIsHidden = isHidden || offscreenSubtreeIsHidden;
-      if (newOffscreenSubtreeIsHidden) {
-        // The Offscreen tree is hidden. Skip over its layout effects.
-        commitLayoutMountEffects_complete(subtreeRoot, root, committedLanes);
-        continue;
-      } else {
-        // TODO (Offscreen) Also check: subtreeFlags & LayoutMask
-        const current = fiber.alternate;
-        const wasHidden = current !== null && current.memoizedState !== null;
-        const newOffscreenSubtreeWasHidden =
-          wasHidden || offscreenSubtreeWasHidden;
-        const prevOffscreenSubtreeIsHidden = offscreenSubtreeIsHidden;
-        const prevOffscreenSubtreeWasHidden = offscreenSubtreeWasHidden;
-
-        // Traverse the Offscreen subtree with the current Offscreen as the root.
-        offscreenSubtreeIsHidden = newOffscreenSubtreeIsHidden;
-        offscreenSubtreeWasHidden = newOffscreenSubtreeWasHidden;
-
-        if (offscreenSubtreeWasHidden && !prevOffscreenSubtreeWasHidden) {
-          // This is the root of a reappearing boundary. Turn its layout effects
-          // back on.
-          nextEffect = fiber;
-          reappearLayoutEffects_begin(fiber);
-        }
-
-        let child = firstChild;
-        while (child !== null) {
-          nextEffect = child;
-          commitLayoutEffects_begin(
-            child, // New root; bubble back up to here and stop.
-            root,
-            committedLanes,
-          );
-          child = child.sibling;
-        }
-
-        // Restore Offscreen state and resume in our-progress traversal.
-        nextEffect = fiber;
-        offscreenSubtreeIsHidden = prevOffscreenSubtreeIsHidden;
-        offscreenSubtreeWasHidden = prevOffscreenSubtreeWasHidden;
-        commitLayoutMountEffects_complete(subtreeRoot, root, committedLanes);
-
-        continue;
-      }
-    }
-
-    if ((fiber.subtreeFlags & LayoutMask) !== NoFlags && firstChild !== null) {
-      firstChild.return = fiber;
-      nextEffect = firstChild;
-    } else {
-      commitLayoutMountEffects_complete(subtreeRoot, root, committedLanes);
-    }
-  }
-}
-
-function commitLayoutMountEffects_complete(
-  subtreeRoot: Fiber,
-  root: FiberRoot,
-  committedLanes: Lanes,
+  parentFiber: Fiber,
+  lanes: Lanes,
 ) {
-  while (nextEffect !== null) {
-    const fiber = nextEffect;
-    if ((fiber.flags & LayoutMask) !== NoFlags) {
-      const current = fiber.alternate;
-      setCurrentDebugFiberInDEV(fiber);
-      commitLayoutEffectOnFiber(root, current, fiber, committedLanes);
-      resetCurrentDebugFiberInDEV();
-    }
-
-    if (fiber === subtreeRoot) {
-      nextEffect = null;
-      return;
-    }
-
-    const sibling = fiber.sibling;
-    if (sibling !== null) {
-      sibling.return = fiber.return;
-      nextEffect = sibling;
-      return;
+  const prevDebugFiber = getCurrentDebugFiberInDEV();
+  if (parentFiber.subtreeFlags & LayoutMask) {
+    let child = parentFiber.child;
+    while (child !== null) {
+      setCurrentDebugFiberInDEV(child);
+      const current = child.alternate;
+      commitLayoutEffectOnFiber(root, current, child, lanes);
+      child = child.sibling;
     }
-
-    nextEffect = fiber.return;
   }
+  setCurrentDebugFiberInDEV(prevDebugFiber);
 }
 
 function disappearLayoutEffects_begin(subtreeRoot: Fiber) {