diff --git a/packages/react-reconciler/src/ReactFiberAsyncAction.js b/packages/react-reconciler/src/ReactFiberAsyncAction.js index 7382aeee89e9f..98f7ca175c0a8 100644 --- a/packages/react-reconciler/src/ReactFiberAsyncAction.js +++ b/packages/react-reconciler/src/ReactFiberAsyncAction.js @@ -9,7 +9,6 @@ import type { Thenable, - PendingThenable, FulfilledThenable, RejectedThenable, } from 'shared/ReactTypes'; @@ -32,111 +31,32 @@ let currentEntangledListeners: Array<() => mixed> | null = null; let currentEntangledPendingCount: number = 0; // The transition lane shared by all updates in the entangled scope. let currentEntangledLane: Lane = NoLane; +// A thenable that resolves when the entangled scope completes. It does not +// resolve to a particular value because it's only used for suspending the UI +// until the async action scope has completed. +let currentEntangledActionThenable: Thenable | null = null; -export function requestAsyncActionContext( - actionReturnValue: Thenable, - // If this is provided, this resulting thenable resolves to this value instead - // of the return value of the action. This is a perf trick to avoid composing - // an extra async function. - overrideReturnValue: S | null, -): Thenable { - // This is an async action. - // - // Return a thenable that resolves once the action scope (i.e. the async - // function passed to startTransition) has finished running. - - const thenable: Thenable = (actionReturnValue: any); - let entangledListeners; +export function entangleAsyncAction(thenable: Thenable): Thenable { + // `thenable` is the return value of the async action scope function. Create + // a combined thenable that resolves once every entangled scope function + // has finished. if (currentEntangledListeners === null) { // There's no outer async action scope. Create a new one. - entangledListeners = currentEntangledListeners = []; + const entangledListeners = (currentEntangledListeners = []); currentEntangledPendingCount = 0; currentEntangledLane = requestTransitionLane(); - } else { - entangledListeners = currentEntangledListeners; + const entangledThenable: Thenable = { + status: 'pending', + value: undefined, + then(resolve: void => mixed) { + entangledListeners.push(resolve); + }, + }; + currentEntangledActionThenable = entangledThenable; } - currentEntangledPendingCount++; - - // Create a thenable that represents the result of this action, but doesn't - // resolve until the entire entangled scope has finished. - // - // Expressed using promises: - // const [thisResult] = await Promise.all([thisAction, entangledAction]); - // return thisResult; - const resultThenable = createResultThenable(entangledListeners); - - let resultStatus = 'pending'; - let resultValue; - let rejectedReason; - thenable.then( - (value: S) => { - resultStatus = 'fulfilled'; - resultValue = overrideReturnValue !== null ? overrideReturnValue : value; - pingEngtangledActionScope(); - }, - error => { - resultStatus = 'rejected'; - rejectedReason = error; - pingEngtangledActionScope(); - }, - ); - - // Attach a listener to fill in the result. - entangledListeners.push(() => { - switch (resultStatus) { - case 'fulfilled': { - const fulfilledThenable: FulfilledThenable = (resultThenable: any); - fulfilledThenable.status = 'fulfilled'; - fulfilledThenable.value = resultValue; - break; - } - case 'rejected': { - const rejectedThenable: RejectedThenable = (resultThenable: any); - rejectedThenable.status = 'rejected'; - rejectedThenable.reason = rejectedReason; - break; - } - case 'pending': - default: { - // The listener above should have been called first, so `resultStatus` - // should already be set to the correct value. - throw new Error( - 'Thenable should have already resolved. This ' + 'is a bug in React.', - ); - } - } - }); - - return resultThenable; -} - -export function requestSyncActionContext( - actionReturnValue: any, - // If this is provided, this resulting thenable resolves to this value instead - // of the return value of the action. This is a perf trick to avoid composing - // an extra async function. - overrideReturnValue: S | null, -): Thenable | S { - const resultValue: S = - overrideReturnValue !== null - ? overrideReturnValue - : (actionReturnValue: any); - // This is not an async action, but it may be part of an outer async action. - if (currentEntangledListeners === null) { - return resultValue; - } else { - // Return a thenable that does not resolve until the entangled actions - // have finished. - const entangledListeners = currentEntangledListeners; - const resultThenable = createResultThenable(entangledListeners); - entangledListeners.push(() => { - const fulfilledThenable: FulfilledThenable = (resultThenable: any); - fulfilledThenable.status = 'fulfilled'; - fulfilledThenable.value = resultValue; - }); - return resultThenable; - } + thenable.then(pingEngtangledActionScope, pingEngtangledActionScope); + return thenable; } function pingEngtangledActionScope() { @@ -146,9 +66,15 @@ function pingEngtangledActionScope() { ) { // All the actions have finished. Close the entangled async action scope // and notify all the listeners. + if (currentEntangledActionThenable !== null) { + const fulfilledThenable: FulfilledThenable = + (currentEntangledActionThenable: any); + fulfilledThenable.status = 'fulfilled'; + } const listeners = currentEntangledListeners; currentEntangledListeners = null; currentEntangledLane = NoLane; + currentEntangledActionThenable = null; for (let i = 0; i < listeners.length; i++) { const listener = listeners[i]; listener(); @@ -156,31 +82,58 @@ function pingEngtangledActionScope() { } } -function createResultThenable( - entangledListeners: Array<() => mixed>, -): Thenable { - // Waits for the entangled async action to complete, then resolves to the - // result of an individual action. - const resultThenable: PendingThenable = { +export function chainThenableValue( + thenable: Thenable, + result: T, +): Thenable { + // Equivalent to: Promise.resolve(thenable).then(() => result), except we can + // cheat a bit since we know that that this thenable is only ever consumed + // by React. + // + // We don't technically require promise support on the client yet, hence this + // extra code. + const listeners = []; + const thenableWithOverride: Thenable = { status: 'pending', value: null, reason: null, - then(resolve: S => mixed) { - // This is a bit of a cheat. `resolve` expects a value of type `S` to be - // passed, but because we're instrumenting the `status` field ourselves, - // and we know this thenable will only be used by React, we also know - // the value isn't actually needed. So we add the resolve function - // directly to the entangled listeners. - // - // This is also why we don't need to check if the thenable is still - // pending; the Suspense implementation already performs that check. - const ping: () => mixed = (resolve: any); - entangledListeners.push(ping); + then(resolve: T => mixed) { + listeners.push(resolve); }, }; - return resultThenable; + thenable.then( + (value: T) => { + const fulfilledThenable: FulfilledThenable = + (thenableWithOverride: any); + fulfilledThenable.status = 'fulfilled'; + fulfilledThenable.value = result; + for (let i = 0; i < listeners.length; i++) { + const listener = listeners[i]; + listener(result); + } + }, + error => { + const rejectedThenable: RejectedThenable = (thenableWithOverride: any); + rejectedThenable.status = 'rejected'; + rejectedThenable.reason = error; + for (let i = 0; i < listeners.length; i++) { + const listener = listeners[i]; + // This is a perf hack where we call the `onFulfill` ping function + // instead of `onReject`, because we know that React is the only + // consumer of these promises, and it passes the same listener to both. + // We also know that it will read the error directly off the + // `.reason` field. + listener((undefined: any)); + } + }, + ); + return thenableWithOverride; } export function peekEntangledActionLane(): Lane { return currentEntangledLane; } + +export function peekEntangledActionThenable(): Thenable | null { + return currentEntangledActionThenable; +} diff --git a/packages/react-reconciler/src/ReactFiberBeginWork.js b/packages/react-reconciler/src/ReactFiberBeginWork.js index f2a96b4d34d9f..5c555b1812d43 100644 --- a/packages/react-reconciler/src/ReactFiberBeginWork.js +++ b/packages/react-reconciler/src/ReactFiberBeginWork.js @@ -137,6 +137,7 @@ import { cloneUpdateQueue, initializeUpdateQueue, enqueueCapturedUpdate, + suspendIfUpdateReadFromEntangledAsyncAction, } from './ReactFiberClassUpdateQueue'; import { NoLane, @@ -945,6 +946,7 @@ function updateCacheComponent( if (includesSomeLane(current.lanes, renderLanes)) { cloneUpdateQueue(current, workInProgress); processUpdateQueue(workInProgress, null, null, renderLanes); + suspendIfUpdateReadFromEntangledAsyncAction(); } const prevState: CacheComponentState = current.memoizedState; const nextState: CacheComponentState = workInProgress.memoizedState; @@ -1475,6 +1477,11 @@ function updateHostRoot( } } + // This would ideally go inside processUpdateQueue, but because it suspends, + // it needs to happen after the `pushCacheProvider` call above to avoid a + // context stack mismatch. A bit unfortunate. + suspendIfUpdateReadFromEntangledAsyncAction(); + // Caution: React DevTools currently depends on this property // being called "element". const nextChildren = nextState.element; diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js index c816fb0ba21ea..cceb78c8ed878 100644 --- a/packages/react-reconciler/src/ReactFiberClassComponent.js +++ b/packages/react-reconciler/src/ReactFiberClassComponent.js @@ -53,6 +53,7 @@ import { ForceUpdate, initializeUpdateQueue, cloneUpdateQueue, + suspendIfUpdateReadFromEntangledAsyncAction, } from './ReactFiberClassUpdateQueue'; import {NoLanes} from './ReactFiberLane'; import { @@ -892,6 +893,7 @@ function mountClassInstance( // If we had additional state updates during this life-cycle, let's // process them now. processUpdateQueue(workInProgress, newProps, instance, renderLanes); + suspendIfUpdateReadFromEntangledAsyncAction(); instance.state = workInProgress.memoizedState; } @@ -959,6 +961,7 @@ function resumeMountClassInstance( const oldState = workInProgress.memoizedState; let newState = (instance.state = oldState); processUpdateQueue(workInProgress, newProps, instance, renderLanes); + suspendIfUpdateReadFromEntangledAsyncAction(); newState = workInProgress.memoizedState; if ( oldProps === newProps && @@ -1109,6 +1112,7 @@ function updateClassInstance( const oldState = workInProgress.memoizedState; let newState = (instance.state = oldState); processUpdateQueue(workInProgress, newProps, instance, renderLanes); + suspendIfUpdateReadFromEntangledAsyncAction(); newState = workInProgress.memoizedState; if ( diff --git a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.js b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.js index 2e88c982022d3..d7a1efbb47f4a 100644 --- a/packages/react-reconciler/src/ReactFiberClassUpdateQueue.js +++ b/packages/react-reconciler/src/ReactFiberClassUpdateQueue.js @@ -125,6 +125,10 @@ import { import {setIsStrictModeForDevtools} from './ReactFiberDevToolsHook'; import assign from 'shared/assign'; +import { + peekEntangledActionLane, + peekEntangledActionThenable, +} from './ReactFiberAsyncAction'; export type Update = { lane: Lane, @@ -463,12 +467,38 @@ function getStateFromUpdate( return prevState; } +let didReadFromEntangledAsyncAction: boolean = false; + +// Each call to processUpdateQueue should be accompanied by a call to this. It's +// only in a separate function because in updateHostRoot, it must happen after +// all the context stacks have been pushed to, to prevent a stack mismatch. A +// bit unfortunate. +export function suspendIfUpdateReadFromEntangledAsyncAction() { + // Check if this update is part of a pending async action. If so, we'll + // need to suspend until the action has finished, so that it's batched + // together with future updates in the same action. + // TODO: Once we support hooks inside useMemo (or an equivalent + // memoization boundary like Forget), hoist this logic so that it only + // suspends if the memo boundary produces a new value. + if (didReadFromEntangledAsyncAction) { + const entangledActionThenable = peekEntangledActionThenable(); + if (entangledActionThenable !== null) { + // TODO: Instead of the throwing the thenable directly, throw a + // special object like `use` does so we can detect if it's captured + // by userspace. + throw entangledActionThenable; + } + } +} + export function processUpdateQueue( workInProgress: Fiber, props: any, instance: any, renderLanes: Lanes, ): void { + didReadFromEntangledAsyncAction = false; + // This is always non-null on a ClassComponent or HostRoot const queue: UpdateQueue = (workInProgress.updateQueue: any); @@ -571,6 +601,13 @@ export function processUpdateQueue( } else { // This update does have sufficient priority. + // Check if this update is part of a pending async action. If so, + // we'll need to suspend until the action has finished, so that it's + // batched together with future updates in the same action. + if (updateLane !== NoLane && updateLane === peekEntangledActionLane()) { + didReadFromEntangledAsyncAction = true; + } + if (newLastBaseUpdate !== null) { const clone: Update = { // This update is going to be committed so we never want uncommit diff --git a/packages/react-reconciler/src/ReactFiberHooks.js b/packages/react-reconciler/src/ReactFiberHooks.js index 12c3987095284..42a9eaa4f477d 100644 --- a/packages/react-reconciler/src/ReactFiberHooks.js +++ b/packages/react-reconciler/src/ReactFiberHooks.js @@ -145,9 +145,10 @@ import { import type {ThenableState} from './ReactFiberThenable'; import type {BatchConfigTransition} from './ReactFiberTracingMarkerComponent'; import { - requestAsyncActionContext, - requestSyncActionContext, + entangleAsyncAction, peekEntangledActionLane, + peekEntangledActionThenable, + chainThenableValue, } from './ReactFiberAsyncAction'; import {HostTransitionContext} from './ReactFiberHostContext'; import {requestTransitionLane} from './ReactFiberRootScheduler'; @@ -1274,6 +1275,7 @@ function updateReducerImpl( let newBaseQueueFirst = null; let newBaseQueueLast: Update | null = null; let update = first; + let didReadFromEntangledAsyncAction = false; do { // An extra OffscreenLane bit is added to updates that were made to // a hidden tree, so that we can distinguish them from updates that were @@ -1317,6 +1319,13 @@ function updateReducerImpl( } else { // This update does have sufficient priority. + // Check if this update is part of a pending async action. If so, + // we'll need to suspend until the action has finished, so that it's + // batched together with future updates in the same action. + if (updateLane !== NoLane && updateLane === peekEntangledActionLane()) { + didReadFromEntangledAsyncAction = true; + } + // Check if this is an optimistic update. const revertLane = update.revertLane; if (!enableAsyncActions || revertLane === NoLane) { @@ -1407,6 +1416,22 @@ function updateReducerImpl( // different from the current state. if (!is(newState, hook.memoizedState)) { markWorkInProgressReceivedUpdate(); + + // Check if this update is part of a pending async action. If so, we'll + // need to suspend until the action has finished, so that it's batched + // together with future updates in the same action. + // TODO: Once we support hooks inside useMemo (or an equivalent + // memoization boundary like Forget), hoist this logic so that it only + // suspends if the memo boundary produces a new value. + if (didReadFromEntangledAsyncAction) { + const entangledActionThenable = peekEntangledActionThenable(); + if (entangledActionThenable !== null) { + // TODO: Instead of the throwing the thenable directly, throw a + // special object like `use` does so we can detect if it's captured + // by userspace. + throw entangledActionThenable; + } + } } hook.memoizedState = newState; @@ -1964,13 +1989,10 @@ function runFormStateAction( () => finishRunningFormStateAction(actionQueue, (setState: any)), ); - const entangledResult = requestAsyncActionContext(thenable, null); - setState((entangledResult: any)); + entangleAsyncAction>(thenable); + setState((thenable: any)); } else { - // This is either `returnValue` or a thenable that resolves to - // `returnValue`, depending on whether we're inside an async action scope. - const entangledResult = requestSyncActionContext(returnValue, null); - setState((entangledResult: any)); + setState((returnValue: any)); const nextState = ((returnValue: any): Awaited); actionQueue.state = nextState; @@ -2832,22 +2854,16 @@ function startTransition( typeof returnValue.then === 'function' ) { const thenable = ((returnValue: any): Thenable); - // This is a thenable that resolves to `finishedState` once the async - // action scope has finished. - const entangledResult = requestAsyncActionContext( + entangleAsyncAction(thenable); + // Create a thenable that resolves to `finishedState` once the async + // action has completed. + const thenableForFinishedState = chainThenableValue( thenable, finishedState, ); - dispatchSetState(fiber, queue, entangledResult); + dispatchSetState(fiber, queue, (thenableForFinishedState: any)); } else { - // This is either `finishedState` or a thenable that resolves to - // `finishedState`, depending on whether we're inside an async - // action scope. - const entangledResult = requestSyncActionContext( - returnValue, - finishedState, - ); - dispatchSetState(fiber, queue, entangledResult); + dispatchSetState(fiber, queue, finishedState); } } else { // Async actions are not enabled. diff --git a/packages/react-reconciler/src/ReactFiberThrow.js b/packages/react-reconciler/src/ReactFiberThrow.js index 789be43b88f36..7633e1c676713 100644 --- a/packages/react-reconciler/src/ReactFiberThrow.js +++ b/packages/react-reconciler/src/ReactFiberThrow.js @@ -206,7 +206,7 @@ function resetSuspendedComponent(sourceFiber: Fiber, rootRenderLanes: Lanes) { function markSuspenseBoundaryShouldCapture( suspenseBoundary: Fiber, - returnFiber: Fiber, + returnFiber: Fiber | null, sourceFiber: Fiber, root: FiberRoot, rootRenderLanes: Lanes, @@ -319,11 +319,11 @@ function markSuspenseBoundaryShouldCapture( function throwException( root: FiberRoot, - returnFiber: Fiber, + returnFiber: Fiber | null, sourceFiber: Fiber, value: mixed, rootRenderLanes: Lanes, -): void { +): boolean { // The source fiber did not complete. sourceFiber.flags |= Incomplete; @@ -446,7 +446,7 @@ function throwException( attachPingListener(root, wakeable, rootRenderLanes); } } - return; + return false; } case OffscreenComponent: { if (suspenseBoundary.mode & ConcurrentMode) { @@ -476,7 +476,7 @@ function throwException( attachPingListener(root, wakeable, rootRenderLanes); } - return; + return false; } } } @@ -497,7 +497,7 @@ function throwException( // and potentially log a warning. Revisit this for a future release. attachPingListener(root, wakeable, rootRenderLanes); renderDidSuspendDelayIfPossible(); - return; + return false; } else { // In a legacy root, suspending without a boundary is always an error. const uncaughtSuspenseError = new Error( @@ -537,7 +537,7 @@ function throwException( // Even though the user may not be affected by this error, we should // still log it so it can be fixed. queueHydrationError(createCapturedValueAtFiber(value, sourceFiber)); - return; + return false; } } else { // Otherwise, fall through to the error path. @@ -549,6 +549,13 @@ function throwException( // We didn't find a boundary that could handle this type of exception. Start // over and traverse parent path again, this time treating the exception // as an error. + + if (returnFiber === null) { + // There's no return fiber, which means the root errored. This should never + // happen. Return `true` to trigger a fatal error (panic). + return true; + } + let workInProgress: Fiber = returnFiber; do { switch (workInProgress.tag) { @@ -559,7 +566,7 @@ function throwException( workInProgress.lanes = mergeLanes(workInProgress.lanes, lane); const update = createRootErrorUpdate(workInProgress, errorInfo, lane); enqueueCapturedUpdate(workInProgress, update); - return; + return false; } case ClassComponent: // Capture and retry @@ -583,7 +590,7 @@ function throwException( lane, ); enqueueCapturedUpdate(workInProgress, update); - return; + return false; } break; default: @@ -592,6 +599,8 @@ function throwException( // $FlowFixMe[incompatible-type] we bail out when we get a null workInProgress = workInProgress.return; } while (workInProgress !== null); + + return false; } export {throwException, createRootErrorUpdate, createClassErrorUpdate}; diff --git a/packages/react-reconciler/src/ReactFiberWorkLoop.js b/packages/react-reconciler/src/ReactFiberWorkLoop.js index 6aaf0e936bd89..d487fdb205c5d 100644 --- a/packages/react-reconciler/src/ReactFiberWorkLoop.js +++ b/packages/react-reconciler/src/ReactFiberWorkLoop.js @@ -1994,7 +1994,7 @@ function renderRootSync(root: FiberRoot, lanes: Lanes) { // Unwind then continue with the normal work loop. workInProgressSuspendedReason = NotSuspended; workInProgressThrownValue = null; - throwAndUnwindWorkLoop(unitOfWork, thrownValue); + throwAndUnwindWorkLoop(root, unitOfWork, thrownValue); break; } } @@ -2114,7 +2114,7 @@ function renderRootConcurrent(root: FiberRoot, lanes: Lanes) { // Unwind then continue with the normal work loop. workInProgressSuspendedReason = NotSuspended; workInProgressThrownValue = null; - throwAndUnwindWorkLoop(unitOfWork, thrownValue); + throwAndUnwindWorkLoop(root, unitOfWork, thrownValue); break; } case SuspendedOnData: { @@ -2172,7 +2172,7 @@ function renderRootConcurrent(root: FiberRoot, lanes: Lanes) { // Otherwise, unwind then continue with the normal work loop. workInProgressSuspendedReason = NotSuspended; workInProgressThrownValue = null; - throwAndUnwindWorkLoop(unitOfWork, thrownValue); + throwAndUnwindWorkLoop(root, unitOfWork, thrownValue); } break; } @@ -2229,7 +2229,7 @@ function renderRootConcurrent(root: FiberRoot, lanes: Lanes) { // Otherwise, unwind then continue with the normal work loop. workInProgressSuspendedReason = NotSuspended; workInProgressThrownValue = null; - throwAndUnwindWorkLoop(unitOfWork, thrownValue); + throwAndUnwindWorkLoop(root, unitOfWork, thrownValue); break; } case SuspendedOnDeprecatedThrowPromise: { @@ -2239,7 +2239,7 @@ function renderRootConcurrent(root: FiberRoot, lanes: Lanes) { // always unwind. workInProgressSuspendedReason = NotSuspended; workInProgressThrownValue = null; - throwAndUnwindWorkLoop(unitOfWork, thrownValue); + throwAndUnwindWorkLoop(root, unitOfWork, thrownValue); break; } case SuspendedOnHydration: { @@ -2464,7 +2464,11 @@ function replaySuspendedUnitOfWork(unitOfWork: Fiber): void { ReactCurrentOwner.current = null; } -function throwAndUnwindWorkLoop(unitOfWork: Fiber, thrownValue: mixed) { +function throwAndUnwindWorkLoop( + root: FiberRoot, + unitOfWork: Fiber, + thrownValue: mixed, +) { // This is a fork of performUnitOfWork specifcally for unwinding a fiber // that threw an exception. // @@ -2473,40 +2477,32 @@ function throwAndUnwindWorkLoop(unitOfWork: Fiber, thrownValue: mixed) { resetSuspendedWorkLoopOnUnwind(unitOfWork); const returnFiber = unitOfWork.return; - if (returnFiber === null || workInProgressRoot === null) { - // Expected to be working on a non-root fiber. This is a fatal error - // because there's no ancestor that can handle it; the root is - // supposed to capture all errors that weren't caught by an error - // boundary. - workInProgressRootExitStatus = RootFatalErrored; - workInProgressRootFatalError = thrownValue; - // Set `workInProgress` to null. This represents advancing to the next - // sibling, or the parent if there are no siblings. But since the root - // has no siblings nor a parent, we set it to null. Usually this is - // handled by `completeUnitOfWork` or `unwindWork`, but since we're - // intentionally not calling those, we need set it here. - // TODO: Consider calling `unwindWork` to pop the contexts. - workInProgress = null; - return; - } - try { // Find and mark the nearest Suspense or error boundary that can handle // this "exception". - throwException( - workInProgressRoot, + const didFatal = throwException( + root, returnFiber, unitOfWork, thrownValue, workInProgressRootRenderLanes, ); + if (didFatal) { + panicOnRootError(thrownValue); + return; + } } catch (error) { // We had trouble processing the error. An example of this happening is // when accessing the `componentDidCatch` property of an error boundary // throws an error. A weird edge case. There's a regression test for this. // To prevent an infinite loop, bubble the error up to the next parent. - workInProgress = returnFiber; - throw error; + if (returnFiber !== null) { + workInProgress = returnFiber; + throw error; + } else { + panicOnRootError(thrownValue); + return; + } } if (unitOfWork.flags & Incomplete) { @@ -2526,6 +2522,22 @@ function throwAndUnwindWorkLoop(unitOfWork: Fiber, thrownValue: mixed) { } } +function panicOnRootError(error: mixed) { + // There's no ancestor that can handle this exception. This should never + // happen because the root is supposed to capture all errors that weren't + // caught by an error boundary. This is a fatal error, or panic condition, + // because we've run out of ways to recover. + workInProgressRootExitStatus = RootFatalErrored; + workInProgressRootFatalError = error; + // Set `workInProgress` to null. This represents advancing to the next + // sibling, or the parent if there are no siblings. But since the root + // has no siblings nor a parent, we set it to null. Usually this is + // handled by `completeUnitOfWork` or `unwindWork`, but since we're + // intentionally not calling those, we need set it here. + // TODO: Consider calling `unwindWork` to pop the contexts. + workInProgress = null; +} + function completeUnitOfWork(unitOfWork: Fiber): void { // Attempt to complete the current unit of work, then move to the next // sibling. If there are no more siblings, return to the parent fiber. diff --git a/packages/react-reconciler/src/__tests__/ReactAsyncActions-test.js b/packages/react-reconciler/src/__tests__/ReactAsyncActions-test.js index 1be91d36084e6..1f45fd84d0430 100644 --- a/packages/react-reconciler/src/__tests__/ReactAsyncActions-test.js +++ b/packages/react-reconciler/src/__tests__/ReactAsyncActions-test.js @@ -1270,4 +1270,375 @@ describe('ReactAsyncActions', () => { assertLog(['Loading... (25%)', 'A', 'B']); expect(root).toMatchRenderedOutput(
B
); }); + + // @gate enableAsyncActions + test( + 'optimistic state is not reverted until async action finishes, even if ' + + 'useTransition hook is unmounted', + async () => { + let startTransition; + function Updater() { + const [isPending, _start] = useTransition(); + startTransition = _start; + return ( + + + + ); + } + + let setText; + let setOptimisticText; + function Sibling() { + const [canonicalText, _setText] = useState('A'); + setText = _setText; + + const [text, _setOptimisticText] = useOptimistic( + canonicalText, + (_, optimisticText) => `${optimisticText} (loading...)`, + ); + setOptimisticText = _setOptimisticText; + + return ( + + + + ); + } + + function App({showUpdater}) { + return ( + <> + {showUpdater ? : null} + + + ); + } + + const root = ReactNoop.createRoot(); + await act(() => { + root.render(); + }); + assertLog(['Pending: false', 'A']); + expect(root).toMatchRenderedOutput( + <> + Pending: false + A + , + ); + + // Start an async action that has multiple updates with async + // operations in between. + await act(() => { + startTransition(async () => { + Scheduler.log('Async action started'); + + setOptimisticText('C'); + + startTransition(() => setText('B')); + + await getText('Wait before updating to C'); + + Scheduler.log('Async action ended'); + startTransition(() => setText('C')); + }); + }); + assertLog([ + 'Async action started', + 'Pending: true', + // Render an optimistic value + 'C (loading...)', + ]); + expect(root).toMatchRenderedOutput( + <> + Pending: true + C (loading...) + , + ); + + // Delete the component that contains the useTransition hook. This + // component no longer blocks the transition from completing. But the + // we're still showing an optimistic state, because the async action has + // not yet finished. + await act(() => { + root.render(); + }); + assertLog(['C (loading...)']); + expect(root).toMatchRenderedOutput(C (loading...)); + + // Finish the async action. Now the optimistic state is reverted and we + // switch to the canonical value. + await act(() => resolveText('Wait before updating to C')); + assertLog(['Async action ended', 'C']); + expect(root).toMatchRenderedOutput(C); + }, + ); + + // @gate enableAsyncActions + test( + 'updates in an async action are entangled even if useTransition hook ' + + 'is unmounted before it finishes', + async () => { + let startTransition; + function Updater() { + const [isPending, _start] = useTransition(); + startTransition = _start; + return ( + + + + ); + } + + let setText; + function Sibling() { + const [text, _setText] = useState('A'); + setText = _setText; + return ( + + + + ); + } + + function App({showUpdater}) { + return ( + <> + {showUpdater ? : null} + + + ); + } + + const root = ReactNoop.createRoot(); + await act(() => { + root.render(); + }); + assertLog(['Pending: false', 'A']); + expect(root).toMatchRenderedOutput( + <> + Pending: false + A + , + ); + + // Start an async action that has multiple updates with async + // operations in between. + await act(() => { + startTransition(async () => { + Scheduler.log('Async action started'); + startTransition(() => setText('B')); + + await getText('Wait before updating to C'); + + Scheduler.log('Async action ended'); + startTransition(() => setText('C')); + }); + }); + assertLog(['Async action started', 'Pending: true']); + expect(root).toMatchRenderedOutput( + <> + Pending: true + A + , + ); + + // Delete the component that contains the useTransition hook. This + // component no longer blocks the transition from completing. But the + // pending update to Sibling should not be allowed to finish, because it's + // part of the async action. + await act(() => { + root.render(); + }); + assertLog(['A']); + expect(root).toMatchRenderedOutput(A); + + // Finish the async action. Notice the intermediate B state was never + // shown, because it was batched with the update that came later in the + // same action. + await act(() => resolveText('Wait before updating to C')); + assertLog(['Async action ended', 'C']); + expect(root).toMatchRenderedOutput(C); + }, + ); + + // @gate enableAsyncActions + test( + 'updates in an async action are entangled even if useTransition hook ' + + 'is unmounted before it finishes (class component)', + async () => { + let startTransition; + function Updater() { + const [isPending, _start] = useTransition(); + startTransition = _start; + return ( + + + + ); + } + + let setText; + class Sibling extends React.Component { + state = {text: 'A'}; + render() { + setText = text => this.setState({text}); + return ( + + + + ); + } + } + + function App({showUpdater}) { + return ( + <> + {showUpdater ? : null} + + + ); + } + + const root = ReactNoop.createRoot(); + await act(() => { + root.render(); + }); + assertLog(['Pending: false', 'A']); + expect(root).toMatchRenderedOutput( + <> + Pending: false + A + , + ); + + // Start an async action that has multiple updates with async + // operations in between. + await act(() => { + startTransition(async () => { + Scheduler.log('Async action started'); + startTransition(() => setText('B')); + + await getText('Wait before updating to C'); + + Scheduler.log('Async action ended'); + startTransition(() => setText('C')); + }); + }); + assertLog(['Async action started', 'Pending: true']); + expect(root).toMatchRenderedOutput( + <> + Pending: true + A + , + ); + + // Delete the component that contains the useTransition hook. This + // component no longer blocks the transition from completing. But the + // pending update to Sibling should not be allowed to finish, because it's + // part of the async action. + await act(() => { + root.render(); + }); + assertLog(['A']); + expect(root).toMatchRenderedOutput(A); + + // Finish the async action. Notice the intermediate B state was never + // shown, because it was batched with the update that came later in the + // same action. + await act(() => resolveText('Wait before updating to C')); + assertLog(['Async action ended', 'C']); + expect(root).toMatchRenderedOutput(C); + + // Check that subsequent updates are unaffected. + await act(() => setText('D')); + assertLog(['D']); + expect(root).toMatchRenderedOutput(D); + }, + ); + + // @gate enableAsyncActions + test( + 'updates in an async action are entangled even if useTransition hook ' + + 'is unmounted before it finishes (root update)', + async () => { + let startTransition; + function Updater() { + const [isPending, _start] = useTransition(); + startTransition = _start; + return ( + + + + ); + } + + let setShowUpdater; + function App({text}) { + const [showUpdater, _setShowUpdater] = useState(true); + setShowUpdater = _setShowUpdater; + return ( + <> + {showUpdater ? : null} + + + + + ); + } + + const root = ReactNoop.createRoot(); + await act(() => { + root.render(); + }); + assertLog(['Pending: false', 'A']); + expect(root).toMatchRenderedOutput( + <> + Pending: false + A + , + ); + + // Start an async action that has multiple updates with async + // operations in between. + await act(() => { + startTransition(async () => { + Scheduler.log('Async action started'); + startTransition(() => root.render()); + + await getText('Wait before updating to C'); + + Scheduler.log('Async action ended'); + startTransition(() => root.render()); + }); + }); + assertLog(['Async action started', 'Pending: true']); + expect(root).toMatchRenderedOutput( + <> + Pending: true + A + , + ); + + // Delete the component that contains the useTransition hook. This + // component no longer blocks the transition from completing. But the + // pending update to Sibling should not be allowed to finish, because it's + // part of the async action. + await act(() => setShowUpdater(false)); + assertLog(['A']); + expect(root).toMatchRenderedOutput(A); + + // Finish the async action. Notice the intermediate B state was never + // shown, because it was batched with the update that came later in the + // same action. + await act(() => resolveText('Wait before updating to C')); + assertLog(['Async action ended', 'C']); + expect(root).toMatchRenderedOutput(C); + + // Check that subsequent updates are unaffected. + await act(() => root.render()); + assertLog(['D']); + expect(root).toMatchRenderedOutput(D); + }, + ); });