Remove fakeCallbackNode (#20799)

Don't need this, because sync tasks are never cancelled. We can do the same thing we do for microtask callbacks.
facebook · Feb 11, 2021 · 47dd9f4 · 47dd9f4
1 parent 114ab52
commit 47dd9f4
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Showing 4 changed files with 14 additions and 24 deletions.
diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.new.js b/packages/react-reconciler/src/ReactFiberWorkLoop.new.js
@@ -726,7 +726,8 @@ function ensureRootIsScheduled(root: FiberRoot, currentTime: number) {
  // TODO: Temporary until we confirm this warning is not fired.
  if (
  existingCallbackNode == null &&
- existingCallbackPriority !== InputDiscreteLanePriority
+ existingCallbackPriority !== InputDiscreteLanePriority &&
+ existingCallbackPriority !== SyncLanePriority
  ) {
  console.error(
  'Expected scheduled callback to exist. This error is likely caused by a bug in React. Please file an issue.',
@@ -747,11 +748,8 @@ function ensureRootIsScheduled(root: FiberRoot, currentTime: number) {
  if (newCallbackPriority === SyncLanePriority) {
  // Special case: Sync React callbacks are scheduled on a special
  // internal queue
-
- // TODO: After enableDiscreteEventMicroTasks lands, we can remove the fake node.
- newCallbackNode = scheduleSyncCallback(
- performSyncWorkOnRoot.bind(null, root),
- );
+ scheduleSyncCallback(performSyncWorkOnRoot.bind(null, root));
+ newCallbackNode = null;
  } else if (newCallbackPriority === SyncBatchedLanePriority) {
  newCallbackNode = scheduleCallback(
  ImmediateSchedulerPriority,

diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.old.js b/packages/react-reconciler/src/ReactFiberWorkLoop.old.js
@@ -726,7 +726,8 @@ function ensureRootIsScheduled(root: FiberRoot, currentTime: number) {
  // TODO: Temporary until we confirm this warning is not fired.
  if (
  existingCallbackNode == null &&
- existingCallbackPriority !== InputDiscreteLanePriority
+ existingCallbackPriority !== InputDiscreteLanePriority &&
+ existingCallbackPriority !== SyncLanePriority
  ) {
  console.error(
  'Expected scheduled callback to exist. This error is likely caused by a bug in React. Please file an issue.',
@@ -747,11 +748,8 @@ function ensureRootIsScheduled(root: FiberRoot, currentTime: number) {
  if (newCallbackPriority === SyncLanePriority) {
  // Special case: Sync React callbacks are scheduled on a special
  // internal queue
-
- // TODO: After enableDiscreteEventMicroTasks lands, we can remove the fake node.
- newCallbackNode = scheduleSyncCallback(
- performSyncWorkOnRoot.bind(null, root),
- );
+ scheduleSyncCallback(performSyncWorkOnRoot.bind(null, root));
+ newCallbackNode = null;
  } else if (newCallbackPriority === SyncBatchedLanePriority) {
  newCallbackNode = scheduleCallback(
  ImmediateSchedulerPriority,

diff --git a/packages/react-reconciler/src/SchedulerWithReactIntegration.new.js b/packages/react-reconciler/src/SchedulerWithReactIntegration.new.js
@@ -57,8 +57,6 @@ export type SchedulerCallback = (isSync: boolean) => SchedulerCallback | null;
 
 type SchedulerCallbackOptions = {timeout?: number, ...};
 
-const fakeCallbackNode = {};
-
 // Except for NoPriority, these correspond to Scheduler priorities. We use
 // ascending numbers so we can compare them like numbers. They start at 90 to
 // avoid clashing with Scheduler's priorities.
@@ -147,6 +145,8 @@ export function scheduleSyncCallback(callback: SchedulerCallback) {
  if (syncQueue === null) {
  syncQueue = [callback];
  // Flush the queue in the next tick, at the earliest.
+ // TODO: Figure out how to remove this It's only here as a last resort if we
+ // forget to explicitly flush.
  immediateQueueCallbackNode = Scheduler_scheduleCallback(
  Scheduler_ImmediatePriority,
  flushSyncCallbackQueueImpl,
@@ -156,13 +156,10 @@ export function scheduleSyncCallback(callback: SchedulerCallback) {
  // we already scheduled one when we created the queue.
  syncQueue.push(callback);
  }
- return fakeCallbackNode;
 }
 
 export function cancelCallback(callbackNode: mixed) {
- if (callbackNode !== fakeCallbackNode) {
- Scheduler_cancelCallback(callbackNode);
- }
+ Scheduler_cancelCallback(callbackNode);
 }
 
 export function flushSyncCallbackQueue() {

diff --git a/packages/react-reconciler/src/SchedulerWithReactIntegration.old.js b/packages/react-reconciler/src/SchedulerWithReactIntegration.old.js
@@ -57,8 +57,6 @@ export type SchedulerCallback = (isSync: boolean) => SchedulerCallback | null;
 
 type SchedulerCallbackOptions = {timeout?: number, ...};
 
-const fakeCallbackNode = {};
-
 // Except for NoPriority, these correspond to Scheduler priorities. We use
 // ascending numbers so we can compare them like numbers. They start at 90 to
 // avoid clashing with Scheduler's priorities.
@@ -147,6 +145,8 @@ export function scheduleSyncCallback(callback: SchedulerCallback) {
  if (syncQueue === null) {
  syncQueue = [callback];
  // Flush the queue in the next tick, at the earliest.
+ // TODO: Figure out how to remove this It's only here as a last resort if we
+ // forget to explicitly flush.
  immediateQueueCallbackNode = Scheduler_scheduleCallback(
  Scheduler_ImmediatePriority,
  flushSyncCallbackQueueImpl,
@@ -156,13 +156,10 @@ export function scheduleSyncCallback(callback: SchedulerCallback) {
  // we already scheduled one when we created the queue.
  syncQueue.push(callback);
  }
- return fakeCallbackNode;
 }
 
 export function cancelCallback(callbackNode: mixed) {
- if (callbackNode !== fakeCallbackNode) {
- Scheduler_cancelCallback(callbackNode);
- }
+ Scheduler_cancelCallback(callbackNode);
 }
 
 export function flushSyncCallbackQueue() {