Schedule prerender after something suspends (#30800)

Adds the concept of a "prerender". These special renders are spawned
whenever something suspends (and we're not already prerendering).

The purpose is to move speculative rendering work into a separate phase
that does not block the UI from updating. For example, during a
transition, if something suspends, we should not speculatively prerender
siblings that will be replaced by a fallback in the UI until *after* the
fallback has been shown to the user.

DiffTrain build for commit e10e868.

Author: acdlite

compiled-rn/VERSION_NATIVE_FB

@@ -1 +1 @@
-19.0.0-native-fb-8b4c54c0-20240904
+19.0.0-native-fb-e10e8681-20240904

compiled-rn/facebook-fbsource/xplat/js/RKJSModules/vendor/react/react-test-renderer/cjs/ReactTestRenderer-dev.js

@@ -7,13 +7,13 @@
  * @noflow
  * @nolint
  * @preventMunge
- * @generated SignedSource<<c6f7f903e1bec097563ebf3f278e6601>>
+ * @generated SignedSource<<c5472110548ebd348fb228d3551e271d>>
  */
 
 "use strict";
 __DEV__ &&
   (function () {
-    function JSCompiler_object_inline_createNodeMock_1089() {
+    function JSCompiler_object_inline_createNodeMock_1082() {
       return null;
     }
     function findHook(fiber, id) {
@@ -854,28 +854,37 @@ __DEV__ &&
       var pendingLanes = root.pendingLanes;
       if (0 === pendingLanes) return 0;
       var nextLanes = 0,
-        suspendedLanes = root.suspendedLanes;
-      root = root.pingedLanes;
+        suspendedLanes = root.suspendedLanes,
+        pingedLanes = root.pingedLanes;
+      root = root.warmLanes;
       var nonIdlePendingLanes = pendingLanes & 134217727;
       0 !== nonIdlePendingLanes
         ? ((pendingLanes = nonIdlePendingLanes & ~suspendedLanes),
           0 !== pendingLanes
             ? (nextLanes = getHighestPriorityLanes(pendingLanes))
-            : ((root &= nonIdlePendingLanes),
-              0 !== root && (nextLanes = getHighestPriorityLanes(root))))
-        : ((pendingLanes &= ~suspendedLanes),
-          0 !== pendingLanes
-            ? (nextLanes = getHighestPriorityLanes(pendingLanes))
-            : 0 !== root && (nextLanes = getHighestPriorityLanes(root)));
+            : ((pingedLanes &= nonIdlePendingLanes),
+              0 !== pingedLanes
+                ? (nextLanes = getHighestPriorityLanes(pingedLanes))
+                : ((pingedLanes = nonIdlePendingLanes & ~root),
+                  0 !== pingedLanes &&
+                    (nextLanes = getHighestPriorityLanes(pingedLanes)))))
+        : ((nonIdlePendingLanes = pendingLanes & ~suspendedLanes),
+          0 !== nonIdlePendingLanes
+            ? (nextLanes = getHighestPriorityLanes(nonIdlePendingLanes))
+            : 0 !== pingedLanes
+              ? (nextLanes = getHighestPriorityLanes(pingedLanes))
+              : ((pingedLanes = pendingLanes & ~root),
+                0 !== pingedLanes &&
+                  (nextLanes = getHighestPriorityLanes(pingedLanes))));
       return 0 === nextLanes
         ? 0
         : 0 !== wipLanes &&
             wipLanes !== nextLanes &&
             0 === (wipLanes & suspendedLanes) &&
             ((suspendedLanes = nextLanes & -nextLanes),
-            (root = wipLanes & -wipLanes),
-            suspendedLanes >= root ||
-              (32 === suspendedLanes && 0 !== (root & 4194176)))
+            (pingedLanes = wipLanes & -wipLanes),
+            suspendedLanes >= pingedLanes ||
+              (32 === suspendedLanes && 0 !== (pingedLanes & 4194176)))
           ? wipLanes
           : nextLanes;
     }
@@ -954,6 +963,7 @@ __DEV__ &&
       root.pendingLanes = remainingLanes;
       root.suspendedLanes = 0;
       root.pingedLanes = 0;
+      root.warmLanes = 0;
       root.expiredLanes &= remainingLanes;
       root.entangledLanes &= remainingLanes;
       root.errorRecoveryDisabledLanes &= remainingLanes;
@@ -10512,7 +10522,8 @@ __DEV__ &&
           markRootSuspended(
             root,
             workInProgressRootRenderLanes,
-            workInProgressDeferredLane
+            workInProgressDeferredLane,
+            workInProgressRootDidSkipSuspendedSiblings
           );
       markRootUpdated(root, lane);
       if (
@@ -10553,7 +10564,8 @@ __DEV__ &&
               markRootSuspended(
                 root,
                 workInProgressRootRenderLanes,
-                workInProgressDeferredLane
+                workInProgressDeferredLane,
+                workInProgressRootDidSkipSuspendedSiblings
               )),
           ensureRootIsScheduled(root),
           2 !== lane ||
@@ -10584,7 +10596,12 @@ __DEV__ &&
         var renderWasConcurrent = shouldTimeSlice;
         do {
           if (didTimeout === RootDidNotComplete)
-            markRootSuspended(root, lanes, 0);
+            markRootSuspended(
+              root,
+              lanes,
+              0,
+              workInProgressRootDidSkipSuspendedSiblings
+            );
           else {
             shouldTimeSlice = root.current.alternate;
             if (
@@ -10616,7 +10633,12 @@ __DEV__ &&
             }
             if (didTimeout === RootFatalErrored) {
               prepareFreshStack(root, 0);
-              markRootSuspended(root, lanes, 0);
+              markRootSuspended(
+                root,
+                lanes,
+                0,
+                workInProgressRootDidSkipSuspendedSiblings
+              );
               break;
             }
             root.finishedWork = shouldTimeSlice;
@@ -10632,7 +10654,8 @@ __DEV__ &&
                     markRootSuspended(
                       renderWasConcurrent,
                       lanes,
-                      workInProgressDeferredLane
+                      workInProgressDeferredLane,
+                      workInProgressRootDidSkipSuspendedSiblings
                     );
                     break a;
                   }
@@ -10667,7 +10690,8 @@ __DEV__ &&
                   markRootSuspended(
                     renderWasConcurrent,
                     lanes,
-                    workInProgressDeferredLane
+                    workInProgressDeferredLane,
+                    workInProgressRootDidSkipSuspendedSiblings
                   );
                   if (0 !== getNextLanes(renderWasConcurrent, 0)) break a;
                   renderWasConcurrent.timeoutHandle = scheduleTimeout(
@@ -10679,7 +10703,8 @@ __DEV__ &&
                       workInProgressTransitions,
                       workInProgressRootDidIncludeRecursiveRenderUpdate,
                       lanes,
-                      workInProgressDeferredLane
+                      workInProgressDeferredLane,
+                      workInProgressRootDidSkipSuspendedSiblings
                     ),
                     didTimeout
                   );
@@ -10692,7 +10717,8 @@ __DEV__ &&
                   workInProgressTransitions,
                   workInProgressRootDidIncludeRecursiveRenderUpdate,
                   lanes,
-                  workInProgressDeferredLane
+                  workInProgressDeferredLane,
+                  workInProgressRootDidSkipSuspendedSiblings
                 );
               }
             }
@@ -10794,26 +10820,31 @@ __DEV__ &&
     function markRootUpdated(root, updatedLanes) {
       root.pendingLanes |= updatedLanes;
       268435456 !== updatedLanes &&
-        ((root.suspendedLanes = 0), (root.pingedLanes = 0));
+        ((root.suspendedLanes = 0),
+        (root.pingedLanes = 0),
+        (root.warmLanes = 0));
       executionContext & RenderContext
         ? (workInProgressRootDidIncludeRecursiveRenderUpdate = !0)
         : executionContext & CommitContext &&
           (didIncludeCommitPhaseUpdate = !0);
       throwIfInfiniteUpdateLoopDetected();
     }
-    function markRootSuspended(root, suspendedLanes, spawnedLane) {
+    function markRootSuspended(
+      root,
+      suspendedLanes,
+      spawnedLane,
+      didSkipSuspendedSiblings
+    ) {
       suspendedLanes &= ~workInProgressRootPingedLanes;
       suspendedLanes &= ~workInProgressRootInterleavedUpdatedLanes;
       root.suspendedLanes |= suspendedLanes;
       root.pingedLanes &= ~suspendedLanes;
-      for (
-        var expirationTimes = root.expirationTimes, lanes = suspendedLanes;
-        0 < lanes;
-
-      ) {
+      didSkipSuspendedSiblings || (root.warmLanes |= suspendedLanes);
+      didSkipSuspendedSiblings = root.expirationTimes;
+      for (var lanes = suspendedLanes; 0 < lanes; ) {
         var index = 31 - clz32(lanes),
           lane = 1 << index;
-        expirationTimes[index] = -1;
+        didSkipSuspendedSiblings[index] = -1;
         lanes &= ~lane;
       }
       0 !== spawnedLane &&
@@ -10843,13 +10874,18 @@ __DEV__ &&
       if (exitStatus === RootFatalErrored)
         return (
           prepareFreshStack(root, 0),
-          markRootSuspended(root, lanes, 0),
+          markRootSuspended(root, lanes, 0, !1),
           ensureRootIsScheduled(root),
           null
         );
       if (exitStatus === RootDidNotComplete)
         return (
-          markRootSuspended(root, lanes, workInProgressDeferredLane),
+          markRootSuspended(
+            root,
+            lanes,
+            workInProgressDeferredLane,
+            workInProgressRootDidSkipSuspendedSiblings
+          ),
           ensureRootIsScheduled(root),
           null
         );
@@ -10926,7 +10962,8 @@ __DEV__ &&
       workInProgressRootRenderLanes = lanes;
       workInProgressSuspendedReason = NotSuspended;
       workInProgressThrownValue = null;
-      workInProgressRootDidAttachPingListener = !1;
+      workInProgressRootDidAttachPingListener =
+        workInProgressRootDidSkipSuspendedSiblings = !1;
       workInProgressRootExitStatus = RootInProgress;
       workInProgressDeferredLane =
         workInProgressRootPingedLanes =
@@ -11045,7 +11082,8 @@ __DEV__ &&
         markRootSuspended(
           workInProgressRoot,
           workInProgressRootRenderLanes,
-          workInProgressDeferredLane
+          workInProgressDeferredLane,
+          workInProgressRootDidSkipSuspendedSiblings
         );
     }
     function renderRootSync(root, lanes) {
@@ -11351,43 +11389,20 @@ __DEV__ &&
         workInProgress = null;
         return;
       }
-      if (unitOfWork.flags & 32768)
-        a: {
-          root = unitOfWork;
-          do {
-            unitOfWork = unwindWork(root.alternate, root);
-            if (null !== unitOfWork) {
-              unitOfWork.flags &= 32767;
-              workInProgress = unitOfWork;
-              break a;
-            }
-            if (0 !== (root.mode & 2)) {
-              stopProfilerTimerIfRunningAndRecordDelta(root, !1);
-              unitOfWork = root.actualDuration;
-              for (thrownValue = root.child; null !== thrownValue; )
-                (unitOfWork += thrownValue.actualDuration),
-                  (thrownValue = thrownValue.sibling);
-              root.actualDuration = unitOfWork;
-            }
-            root = root.return;
-            null !== root &&
-              ((root.flags |= 32768),
-              (root.subtreeFlags = 0),
-              (root.deletions = null));
-            workInProgress = root;
-          } while (null !== root);
-          workInProgressRootExitStatus = RootDidNotComplete;
-          workInProgress = null;
-        }
-      else completeUnitOfWork(unitOfWork);
+      unitOfWork.flags & 32768
+        ? unwindUnitOfWork(unitOfWork, !0)
+        : completeUnitOfWork(unitOfWork);
     }
     function completeUnitOfWork(unitOfWork) {
       var completedWork = unitOfWork;
       do {
-        0 !== (completedWork.flags & 32768) &&
-          error$jscomp$0(
-            "Internal React error: Expected this fiber to be complete, but it isn't. It should have been unwound. This is a bug in React."
+        if (0 !== (completedWork.flags & 32768)) {
+          unwindUnitOfWork(
+            completedWork,
+            workInProgressRootDidSkipSuspendedSiblings
           );
+          return;
+        }
         var current = completedWork.alternate;
         unitOfWork = completedWork.return;
         0 === (completedWork.mode & 2)
@@ -11421,6 +11436,38 @@ __DEV__ &&
       workInProgressRootExitStatus === RootInProgress &&
         (workInProgressRootExitStatus = RootCompleted);
     }
+    function unwindUnitOfWork(unitOfWork, skipSiblings) {
+      do {
+        var next = unwindWork(unitOfWork.alternate, unitOfWork);
+        if (null !== next) {
+          next.flags &= 32767;
+          workInProgress = next;
+          return;
+        }
+        if (0 !== (unitOfWork.mode & 2)) {
+          stopProfilerTimerIfRunningAndRecordDelta(unitOfWork, !1);
+          next = unitOfWork.actualDuration;
+          for (var child = unitOfWork.child; null !== child; )
+            (next += child.actualDuration), (child = child.sibling);
+          unitOfWork.actualDuration = next;
+        }
+        next = unitOfWork.return;
+        null !== next &&
+          ((next.flags |= 32768),
+          (next.subtreeFlags = 0),
+          (next.deletions = null));
+        if (
+          !skipSiblings &&
+          ((unitOfWork = unitOfWork.sibling), null !== unitOfWork)
+        ) {
+          workInProgress = unitOfWork;
+          return;
+        }
+        workInProgress = unitOfWork = next;
+      } while (null !== unitOfWork);
+      workInProgressRootExitStatus = RootDidNotComplete;
+      workInProgress = null;
+    }
     function commitRoot(
       root,
       recoverableErrors,
@@ -11827,6 +11874,7 @@ __DEV__ &&
       var pingCache = root.pingCache;
       null !== pingCache && pingCache.delete(wakeable);
       root.pingedLanes |= root.suspendedLanes & pingedLanes;
+      root.warmLanes &= ~pingedLanes;
       executionContext & RenderContext
         ? (workInProgressRootDidIncludeRecursiveRenderUpdate = !0)
         : executionContext & CommitContext &&
@@ -12540,6 +12588,7 @@ __DEV__ &&
         this.errorRecoveryDisabledLanes =
         this.finishedLanes =
         this.expiredLanes =
+        this.warmLanes =
         this.pingedLanes =
         this.suspendedLanes =
         this.pendingLanes =
@@ -14703,6 +14752,7 @@ __DEV__ &&
       SuspendedOnHydration = 8,
       workInProgressSuspendedReason = NotSuspended,
       workInProgressThrownValue = null,
+      workInProgressRootDidSkipSuspendedSiblings = !1,
       workInProgressRootDidAttachPingListener = !1,
       entangledRenderLanes = 0,
       workInProgressRootExitStatus = RootInProgress,
@@ -14952,11 +15002,11 @@ __DEV__ &&
     (function () {
       var internals = {
         bundleType: 1,
-        version: "19.0.0-native-fb-8b4c54c0-20240904",
+        version: "19.0.0-native-fb-e10e8681-20240904",
         rendererPackageName: "react-test-renderer",
         currentDispatcherRef: ReactSharedInternals,
         findFiberByHostInstance: getInstanceFromNode,
-        reconcilerVersion: "19.0.0-native-fb-8b4c54c0-20240904"
+        reconcilerVersion: "19.0.0-native-fb-e10e8681-20240904"
       };
       internals.overrideHookState = overrideHookState;
       internals.overrideHookStateDeletePath = overrideHookStateDeletePath;
@@ -14978,7 +15028,7 @@ __DEV__ &&
     exports._Scheduler = Scheduler;
     exports.act = act;
     exports.create = function (element, options) {
-      var createNodeMock = JSCompiler_object_inline_createNodeMock_1089,
+      var createNodeMock = JSCompiler_object_inline_createNodeMock_1082,
         isConcurrent = !1,
         isStrictMode = !1;
       "object" === typeof options &&
@@ -15101,5 +15151,5 @@ __DEV__ &&
             flushSyncWorkAcrossRoots_impl(0, !0));
       }
     };
-    exports.version = "19.0.0-native-fb-8b4c54c0-20240904";
+    exports.version = "19.0.0-native-fb-e10e8681-20240904";
   })();