Import Scheduler directly, not via host config

packages/react-art/src/ReactARTHostConfig.js

@@ -343,8 +343,6 @@ export function getChildHostContext() {
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export const schedulePassiveEffects = scheduleDeferredCallback;
-export const cancelPassiveEffects = cancelDeferredCallback;
 
 export function shouldSetTextContent(type, props) {
   return (

packages/react-dom/src/client/ReactDOMHostConfig.js

@@ -310,8 +310,6 @@ export const scheduleTimeout =
 export const cancelTimeout =
   typeof clearTimeout === 'function' ? clearTimeout : (undefined: any);
 export const noTimeout = -1;
-export const schedulePassiveEffects = scheduleDeferredCallback;
-export const cancelPassiveEffects = cancelDeferredCallback;
 
 // -------------------
 //     Mutation

packages/react-native-renderer/src/ReactFabricHostConfig.js

@@ -20,12 +20,6 @@ import {
   warnForStyleProps,
 } from './NativeMethodsMixinUtils';
 import {create, diff} from './ReactNativeAttributePayload';
-import {
-  now as ReactNativeFrameSchedulingNow,
-  cancelDeferredCallback as ReactNativeFrameSchedulingCancelDeferredCallback,
-  scheduleDeferredCallback as ReactNativeFrameSchedulingScheduleDeferredCallback,
-  shouldYield as ReactNativeFrameSchedulingShouldYield,
-} from './ReactNativeFrameScheduling';
 import {get as getViewConfigForType} from 'ReactNativeViewConfigRegistry';
 
 import deepFreezeAndThrowOnMutationInDev from 'deepFreezeAndThrowOnMutationInDev';
@@ -333,16 +327,10 @@ export function shouldSetTextContent(type: string, props: Props): boolean {
 
 // The Fabric renderer is secondary to the existing React Native renderer.
 export const isPrimaryRenderer = false;
-export const now = ReactNativeFrameSchedulingNow;
-export const scheduleDeferredCallback = ReactNativeFrameSchedulingScheduleDeferredCallback;
-export const cancelDeferredCallback = ReactNativeFrameSchedulingCancelDeferredCallback;
-export const shouldYield = ReactNativeFrameSchedulingShouldYield;
 
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export const schedulePassiveEffects = scheduleDeferredCallback;
-export const cancelPassiveEffects = cancelDeferredCallback;
 
 // -------------------
 //     Persistence

packages/react-native-renderer/src/ReactNativeHostConfig.js

@@ -23,12 +23,6 @@ import {
   updateFiberProps,
 } from './ReactNativeComponentTree';
 import ReactNativeFiberHostComponent from './ReactNativeFiberHostComponent';
-import {
-  now as ReactNativeFrameSchedulingNow,
-  cancelDeferredCallback as ReactNativeFrameSchedulingCancelDeferredCallback,
-  scheduleDeferredCallback as ReactNativeFrameSchedulingScheduleDeferredCallback,
-  shouldYield as ReactNativeFrameSchedulingShouldYield,
-} from './ReactNativeFrameScheduling';
 
 export type Type = string;
 export type Props = Object;
@@ -234,17 +228,11 @@ export function resetAfterCommit(containerInfo: Container): void {
   // Noop
 }
 
-export const now = ReactNativeFrameSchedulingNow;
 export const isPrimaryRenderer = true;
-export const scheduleDeferredCallback = ReactNativeFrameSchedulingScheduleDeferredCallback;
-export const cancelDeferredCallback = ReactNativeFrameSchedulingCancelDeferredCallback;
-export const shouldYield = ReactNativeFrameSchedulingShouldYield;
 
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export const schedulePassiveEffects = scheduleDeferredCallback;
-export const cancelPassiveEffects = cancelDeferredCallback;
 
 export function shouldDeprioritizeSubtree(type: string, props: Props): boolean {
   return false;

packages/react-noop-renderer/src/createReactNoop.js

@@ -304,18 +304,10 @@ function createReactNoop(reconciler: Function, useMutation: boolean) {
       return inst;
     },
 
-    scheduleDeferredCallback: Scheduler.unstable_scheduleCallback,
-    cancelDeferredCallback: Scheduler.unstable_cancelCallback,
-
-    shouldYield: Scheduler.unstable_shouldYield,
-
     scheduleTimeout: setTimeout,
     cancelTimeout: clearTimeout,
     noTimeout: -1,
 
-    schedulePassiveEffects: Scheduler.unstable_scheduleCallback,
-    cancelPassiveEffects: Scheduler.unstable_cancelCallback,
-
     prepareForCommit(): void {},
 
     resetAfterCommit(): void {},

packages/react-reconciler/src/ReactFiberScheduler.js

@@ -14,9 +14,7 @@ import type {Interaction} from 'scheduler/src/Tracing';
 
 // Intentionally not named imports because Rollup would use dynamic dispatch for
 // CommonJS interop named imports.
-// TODO: We're not using this import anymore, but I've left this here so we
-// don't accidentally use named imports when we add it back.
-// import * as Scheduler from 'scheduler';
+import * as Scheduler from 'scheduler';
 import {
   __interactionsRef,
   __subscriberRef,
@@ -78,17 +76,11 @@ import {
   setCurrentFiber,
 } from './ReactCurrentFiber';
 import {
-  now,
-  scheduleDeferredCallback,
-  cancelDeferredCallback,
-  shouldYield,
   prepareForCommit,
   resetAfterCommit,
   scheduleTimeout,
   cancelTimeout,
   noTimeout,
-  schedulePassiveEffects,
-  cancelPassiveEffects,
 } from './ReactFiberHostConfig';
 import {
   markPendingPriorityLevel,
@@ -172,6 +164,15 @@ import {
 } from './ReactFiberCommitWork';
 import {ContextOnlyDispatcher} from './ReactFiberHooks';
 
+// Intentionally not named imports because Rollup would use dynamic dispatch for
+// CommonJS interop named imports.
+const {
+  unstable_scheduleCallback: scheduleCallback,
+  unstable_cancelCallback: cancelCallback,
+  unstable_shouldYield: shouldYield,
+  unstable_now: now,
+} = Scheduler;
+
 export type Thenable = {
   then(resolve: () => mixed, reject?: () => mixed): mixed,
 };
@@ -598,7 +599,7 @@ function markLegacyErrorBoundaryAsFailed(instance: mixed) {
 
 function flushPassiveEffects() {
   if (passiveEffectCallbackHandle !== null) {
-    cancelPassiveEffects(passiveEffectCallbackHandle);
+    cancelCallback(passiveEffectCallbackHandle);
   }
   if (passiveEffectCallback !== null) {
     // We call the scheduled callback instead of commitPassiveEffects directly
@@ -807,7 +808,7 @@ function commitRoot(root: FiberRoot, finishedWork: Fiber): void {
       // here because that code is still in flux.
       callback = Scheduler_tracing_wrap(callback);
     }
-    passiveEffectCallbackHandle = schedulePassiveEffects(callback);
+    passiveEffectCallbackHandle = scheduleCallback(callback);
     passiveEffectCallback = callback;
   }
 
@@ -1978,7 +1979,7 @@ function scheduleCallbackWithExpirationTime(
       if (callbackID !== null) {
         // Existing callback has insufficient timeout. Cancel and schedule a
         // new one.
-        cancelDeferredCallback(callbackID);
+        cancelCallback(callbackID);
       }
     }
     // The request callback timer is already running. Don't start a new one.
@@ -1990,7 +1991,7 @@ function scheduleCallbackWithExpirationTime(
   const currentMs = now() - originalStartTimeMs;
   const expirationTimeMs = expirationTimeToMs(expirationTime);
   const timeout = expirationTimeMs - currentMs;
-  callbackID = scheduleDeferredCallback(performAsyncWork, {timeout});
+  callbackID = scheduleCallback(performAsyncWork, {timeout});
 }
 
 // For every call to renderRoot, one of onFatal, onComplete, onSuspend, and

packages/react-reconciler/src/ReactProfilerTimer.js

@@ -11,7 +11,11 @@ import type {Fiber} from './ReactFiber';
 
 import {enableProfilerTimer} from 'shared/ReactFeatureFlags';
 
-import {now} from './ReactFiberHostConfig';
+// Intentionally not named imports because Rollup would use dynamic dispatch for
+// CommonJS interop named imports.
+import * as Scheduler from 'scheduler';
+
+const {unstable_now: now} = Scheduler;
 
 export type ProfilerTimer = {
   getCommitTime(): number,

packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js

@@ -51,14 +51,9 @@ export const shouldSetTextContent = $$$hostConfig.shouldSetTextContent;
 export const shouldDeprioritizeSubtree =
   $$$hostConfig.shouldDeprioritizeSubtree;
 export const createTextInstance = $$$hostConfig.createTextInstance;
-export const scheduleDeferredCallback = $$$hostConfig.scheduleDeferredCallback;
-export const cancelDeferredCallback = $$$hostConfig.cancelDeferredCallback;
-export const shouldYield = $$$hostConfig.shouldYield;
 export const scheduleTimeout = $$$hostConfig.setTimeout;
 export const cancelTimeout = $$$hostConfig.clearTimeout;
 export const noTimeout = $$$hostConfig.noTimeout;
-export const schedulePassiveEffects = $$$hostConfig.schedulePassiveEffects;
-export const cancelPassiveEffects = $$$hostConfig.cancelPassiveEffects;
 export const now = $$$hostConfig.now;
 export const isPrimaryRenderer = $$$hostConfig.isPrimaryRenderer;
 export const supportsMutation = $$$hostConfig.supportsMutation;

packages/react-test-renderer/src/ReactTestHostConfig.js

@@ -7,7 +7,6 @@
  * @flow
  */
 
-import * as Scheduler from 'scheduler/unstable_mock';
 import warning from 'shared/warning';
 
 export type Type = string;
@@ -195,18 +194,10 @@ export function createTextInstance(
 }
 
 export const isPrimaryRenderer = false;
-// This approach enables `now` to be mocked by tests,
-// Even after the reconciler has initialized and read host config values.
-export const now = Scheduler.unstable_now;
-export const scheduleDeferredCallback = Scheduler.unstable_scheduleCallback;
-export const cancelDeferredCallback = Scheduler.unstable_cancelCallback;
-export const shouldYield = Scheduler.unstable_shouldYield;
 
 export const scheduleTimeout = setTimeout;
 export const cancelTimeout = clearTimeout;
 export const noTimeout = -1;
-export const schedulePassiveEffects = Scheduler.unstable_scheduleCallback;
-export const cancelPassiveEffects = Scheduler.unstable_cancelCallback;
 
 // -------------------
 //     Mutation

packages/react/src/__tests__/ReactProfiler-test.internal.js

@@ -261,7 +261,7 @@ describe('Profiler', () => {
       it('does not record times for components outside of Profiler tree', () => {
         // Mock the Scheduler module so we can track how many times the current
         // time is read
-        jest.mock('scheduler/unstable_mock', obj => {
+        jest.mock('scheduler', obj => {
           const ActualScheduler = require.requireActual(
             'scheduler/unstable_mock',
           );
@@ -300,8 +300,10 @@ describe('Profiler', () => {
           'read current time',
         ]);
 
-        // Remove mock
-        jest.unmock('scheduler/unstable_mock');
+        // Restore original mock
+        jest.mock('scheduler', () =>
+          require.requireActual('scheduler/unstable_mock'),
+        );
       });
 
       it('logs render times for both mount and update', () => {