Repository: facebook/react
Pull request: Revert "Fix: Detect infinite update loops caused by render phase updates (#26625)"

This reverts commit 822386f252fd1f0e949efa904a1ed790133329f7.

This broke a number of tests when synced internally. We'll need to investigate the breakages before relanding this.

Changed files:
filename: packages/react-dom/src/__tests__/ReactUpdates-test.js
patch: @@ -1620,64 +1620,6 @@ describe('ReactUpdates', () => {
     });
   });
 
-  it("does not infinite loop if there's a synchronous render phase update on another component", () => {
-    let setState;
-    function App() {
-      const [, _setState] = React.useState(0);
-      setState = _setState;
-      return <Child />;
-    }
-
-    function Child(step) {
-      // This will cause an infinite update loop, and a warning in dev.
-      setState(n => n + 1);
-      return null;
-    }
-
-    const container = document.createElement('div');
-    const root = ReactDOMClient.createRoot(container);
-
-    expect(() => {
-      expect(() => ReactDOM.flushSync(() => root.render(<App />))).toThrow(
-        'Maximum update depth exceeded',
-      );
-    }).toErrorDev(
-      'Warning: Cannot update a component (`App`) while rendering a different component (`Child`)',
-    );
-  });
-
-  it("does not infinite loop if there's an async render phase update on another component", async () => {
-    let setState;
-    function App() {
-      const [, _setState] = React.useState(0);
-      setState = _setState;
-      return <Child />;
-    }
-
-    function Child(step) {
-      // This will cause an infinite update loop, and a warning in dev.
-      setState(n => n + 1);
-      return null;
-    }
-
-    const container = document.createElement('div');
-    const root = ReactDOMClient.createRoot(container);
-
-    await expect(async () => {
-      let error;
-      try {
-        await act(() => {
-          React.startTransition(() => root.render(<App />));
-        });
-      } catch (e) {
-        error = e;
-      }
-      expect(error.message).toMatch('Maximum update depth exceeded');
-    }).toErrorDev(
-      'Warning: Cannot update a component (`App`) while rendering a different component (`Child`)',
-    );
-  });
-
   // TODO: Replace this branch with @gate pragmas
   if (__DEV__) {
     it('warns about a deferred infinite update loop with useEffect', async () => {

filename: packages/react-reconciler/src/ReactFiberRootScheduler.js
patch: @@ -139,18 +139,6 @@ export function ensureRootIsScheduled(root: FiberRoot): void {
   }
 }
 
-function unscheduleAllRoots() {
-  // This is only done in a fatal error situation, as a last resort to prevent
-  // an infinite render loop.
-  let root = firstScheduledRoot;
-  while (root !== null) {
-    const next = root.next;
-    root.next = null;
-    root = next;
-  }
-  firstScheduledRoot = lastScheduledRoot = null;
-}
-
 export function flushSyncWorkOnAllRoots() {
   // This is allowed to be called synchronously, but the caller should check
   // the execution context first.
@@ -181,47 +169,10 @@ function flushSyncWorkAcrossRoots_impl(onlyLegacy: boolean) {
 
   // There may or may not be synchronous work scheduled. Let's check.
   let didPerformSomeWork;
-  let nestedUpdatePasses = 0;
   let errors: Array<mixed> | null = null;
   isFlushingWork = true;
   do {
     didPerformSomeWork = false;
-
-    // This outer loop re-runs if performing sync work on a root spawns
-    // additional sync work. If it happens too many times, it's very likely
-    // caused by some sort of infinite update loop. We already have a loop guard
-    // in place that will trigger an error on the n+1th update, but it's
-    // possible for that error to get swallowed if the setState is called from
-    // an unexpected place, like during the render phase. So as an added
-    // precaution, we also use a guard here.
-    //
-    // Ideally, there should be no known way to trigger this synchronous loop.
-    // It's really just here as a safety net.
-    //
-    // This limit is slightly larger than the one that throws inside setState,
-    // because that one is preferable because it includes a componens stack.
-    if (++nestedUpdatePasses > 60) {
-      // This is a fatal error, so we'll unschedule all the roots.
-      unscheduleAllRoots();
-      // TODO: Change this error message to something different to distinguish
-      // it from the one that is thrown from setState. Those are less fatal
-      // because they usually will result in the bad component being unmounted,
-      // and an error boundary being triggered, rather than us having to
-      // forcibly stop the entire scheduler.
-      const infiniteUpdateError = new Error(
-        'Maximum update depth exceeded. This can happen when a component ' +
-          'repeatedly calls setState inside componentWillUpdate or ' +
-          'componentDidUpdate. React limits the number of nested updates to ' +
-          'prevent infinite loops.',
-      );
-      if (errors === null) {
-        errors = [infiniteUpdateError];
-      } else {
-        errors.push(infiniteUpdateError);
-      }
-      break;
-    }
-
     let root = firstScheduledRoot;
     while (root !== null) {
       if (onlyLegacy && root.tag !== LegacyRoot) {

filename: packages/react-reconciler/src/ReactFiberWorkLoop.js
patch: @@ -141,9 +141,9 @@ import {
   includesExpiredLane,
   getNextLanes,
   getLanesToRetrySynchronouslyOnError,
-  markRootSuspended as _markRootSuspended,
-  markRootUpdated as _markRootUpdated,
-  markRootPinged as _markRootPinged,
+  markRootUpdated,
+  markRootSuspended as markRootSuspended_dontCallThisOneDirectly,
+  markRootPinged,
   markRootEntangled,
   markRootFinished,
   addFiberToLanesMap,
@@ -370,13 +370,6 @@ let workInProgressRootConcurrentErrors: Array<CapturedValue<mixed>> | null =
 let workInProgressRootRecoverableErrors: Array<CapturedValue<mixed>> | null =
   null;
 
-// Tracks when an update occurs during the render phase.
-let workInProgressRootDidIncludeRecursiveRenderUpdate: boolean = false;
-// Thacks when an update occurs during the commit phase. It's a separate
-// variable from the one for renders because the commit phase may run
-// concurrently to a render phase.
-let didIncludeCommitPhaseUpdate: boolean = false;
-
 // The most recent time we either committed a fallback, or when a fallback was
 // filled in with the resolved UI. This lets us throttle the appearance of new
 // content as it streams in, to minimize jank.
@@ -1121,7 +1114,6 @@ function finishConcurrentRender(
       root,
       workInProgressRootRecoverableErrors,
       workInProgressTransitions,
-      workInProgressRootDidIncludeRecursiveRenderUpdate,
     );
   } else {
     if (
@@ -1156,7 +1148,6 @@ function finishConcurrentRender(
             finishedWork,
             workInProgressRootRecoverableErrors,
             workInProgressTransitions,
-            workInProgressRootDidIncludeRecursiveRenderUpdate,
             lanes,
           ),
           msUntilTimeout,
@@ -1169,7 +1160,6 @@ function finishConcurrentRender(
       finishedWork,
       workInProgressRootRecoverableErrors,
       workInProgressTransitions,
-      workInProgressRootDidIncludeRecursiveRenderUpdate,
       lanes,
     );
   }
@@ -1180,7 +1170,6 @@ function commitRootWhenReady(
   finishedWork: Fiber,
   recoverableErrors: Array<CapturedValue<mixed>> | null,
   transitions: Array<Transition> | null,
-  didIncludeRenderPhaseUpdate: boolean,
   lanes: Lanes,
 ) {
   // TODO: Combine retry throttling with Suspensey commits. Right now they run
@@ -1207,21 +1196,15 @@ function commitRootWhenReady(
       // us that it's ready. This will be canceled if we start work on the
       // root again.
       root.cancelPendingCommit = schedulePendingCommit(
-        commitRoot.bind(
-          null,
-          root,
-          recoverableErrors,
-          transitions,
-          didIncludeRenderPhaseUpdate,
-        ),
+        commitRoot.bind(null, root, recoverableErrors, transitions),
       );
       markRootSuspended(root, lanes);
       return;
     }
   }
 
   // Otherwise, commit immediately.
-  commitRoot(root, recoverableErrors, transitions, didIncludeRenderPhaseUpdate);
+  commitRoot(root, recoverableErrors, transitions);
 }
 
 function isRenderConsistentWithExternalStores(finishedWork: Fiber): boolean {
@@ -1277,51 +1260,17 @@ function isRenderConsistentWithExternalStores(finishedWork: Fiber): boolean {
   return true;
 }
 
-// The extra indirections around markRootUpdated and markRootSuspended is
-// needed to avoid a circular dependency between this module and
-// ReactFiberLane. There's probably a better way to split up these modules and
-// avoid this problem. Perhaps all the root-marking functions should move into
-// the work loop.
-
-function markRootUpdated(root: FiberRoot, updatedLanes: Lanes) {
-  _markRootUpdated(root, updatedLanes);
-
-  // Check for recursive updates
-  if (executionContext & RenderContext) {
-    workInProgressRootDidIncludeRecursiveRenderUpdate = true;
-  } else if (executionContext & CommitContext) {
-    didIncludeCommitPhaseUpdate = true;
-  }
-
-  throwIfInfiniteUpdateLoopDetected();
-}
-
-function markRootPinged(root: FiberRoot, pingedLanes: Lanes) {
-  _markRootPinged(root, pingedLanes);
-
-  // Check for recursive pings. Pings are conceptually different from updates in
-  // other contexts but we call it an "update" in this context because
-  // repeatedly pinging a suspended render can cause a recursive render loop.
-  // The relevant property is that it can result in a new render attempt
-  // being scheduled.
-  if (executionContext & RenderContext) {
-    workInProgressRootDidIncludeRecursiveRenderUpdate = true;
-  } else if (executionContext & CommitContext) {
-    didIncludeCommitPhaseUpdate = true;
-  }
-
-  throwIfInfiniteUpdateLoopDetected();
-}
-
 function markRootSuspended(root: FiberRoot, suspendedLanes: Lanes) {
   // When suspending, we should always exclude lanes that were pinged or (more
   // rarely, since we try to avoid it) updated during the render phase.
+  // TODO: Lol maybe there's a better way to factor this besides this
+  // obnoxiously named function :)
   suspendedLanes = removeLanes(suspendedLanes, workInProgressRootPingedLanes);
   suspendedLanes = removeLanes(
     suspendedLanes,
     workInProgressRootInterleavedUpdatedLanes,
   );
-  _markRootSuspended(root, suspendedLanes);
+  markRootSuspended_dontCallThisOneDirectly(root, suspendedLanes);
 }
 
 // This is the entry point for synchronous tasks that don't go
@@ -1392,7 +1341,6 @@ export function performSyncWorkOnRoot(root: FiberRoot): null {
     root,
     workInProgressRootRecoverableErrors,
     workInProgressTransitions,
-    workInProgressRootDidIncludeRecursiveRenderUpdate,
   );
 
   // Before exiting, make sure there's a callback scheduled for the next
@@ -1607,7 +1555,6 @@ function prepareFreshStack(root: FiberRoot, lanes: Lanes): Fiber {
   workInProgressRootPingedLanes = NoLanes;
   workInProgressRootConcurrentErrors = null;
   workInProgressRootRecoverableErrors = null;
-  workInProgressRootDidIncludeRecursiveRenderUpdate = false;
 
   finishQueueingConcurrentUpdates();
 
@@ -2649,7 +2596,6 @@ function commitRoot(
   root: FiberRoot,
   recoverableErrors: null | Array<CapturedValue<mixed>>,
   transitions: Array<Transition> | null,
-  didIncludeRenderPhaseUpdate: boolean,
 ) {
   // TODO: This no longer makes any sense. We already wrap the mutation and
   // layout phases. Should be able to remove.
@@ -2663,7 +2609,6 @@ function commitRoot(
       root,
       recoverableErrors,
       transitions,
-      didIncludeRenderPhaseUpdate,
       previousUpdateLanePriority,
     );
   } finally {
@@ -2678,7 +2623,6 @@ function commitRootImpl(
   root: FiberRoot,
   recoverableErrors: null | Array<CapturedValue<mixed>>,
   transitions: Array<Transition> | null,
-  didIncludeRenderPhaseUpdate: boolean,
   renderPriorityLevel: EventPriority,
 ) {
   do {
@@ -2758,9 +2702,6 @@ function commitRootImpl(
 
   markRootFinished(root, remainingLanes);
 
-  // Reset this before firing side effects so we can detect recursive updates.
-  didIncludeCommitPhaseUpdate = false;
-
   if (root === workInProgressRoot) {
     // We can reset these now that they are finished.
     workInProgressRoot = null;
@@ -3007,19 +2948,7 @@ function commitRootImpl(
 
   // Read this again, since a passive effect might have updated it
   remainingLanes = root.pendingLanes;
-  if (
-    // Check if there was a recursive update spawned by this render, in either
-    // the render phase or the commit phase. We track these explicitly because
-    // we can't infer from the remaining lanes alone.
-    didIncludeCommitPhaseUpdate ||
-    didIncludeRenderPhaseUpdate ||
-    // As an additional precaution, we also check if there's any remaining sync
-    // work. Theoretically this should be unreachable but if there's a mistake
-    // in React it helps to be overly defensive given how hard it is to debug
-    // those scenarios otherwise. This won't catch recursive async updates,
-    // though, which is why we check the flags above first.
-    includesSyncLane(remainingLanes)
-  ) {
+  if (includesSyncLane(remainingLanes)) {
     if (enableProfilerTimer && enableProfilerNestedUpdatePhase) {
       markNestedUpdateScheduled();
     }
@@ -3561,17 +3490,6 @@ export function throwIfInfiniteUpdateLoopDetected() {
     rootWithNestedUpdates = null;
     rootWithPassiveNestedUpdates = null;
 
-    if (executionContext & RenderContext && workInProgressRoot !== null) {
-      // We're in the render phase. Disable the concurrent error recovery
-      // mechanism to ensure that the error we're about to throw gets handled.
-      // We need it to trigger the nearest error boundary so that the infinite
-      // update loop is broken.
-      workInProgressRoot.errorRecoveryDisabledLanes = mergeLanes(
-        workInProgressRoot.errorRecoveryDisabledLanes,
-        workInProgressRootRenderLanes,
-      );
-    }
-
     throw new Error(
       'Maximum update depth exceeded. This can happen when a component ' +
         'repeatedly calls setState inside componentWillUpdate or ' +

filename: scripts/jest/matchers/toWarnDev.js
patch: @@ -69,16 +69,12 @@ const createMatcherFor = (consoleMethod, matcherName) =>
         (message.includes('\n    in ') || message.includes('\n    at '));
 
       const consoleSpy = (format, ...args) => {
+        // Ignore uncaught errors reported by jsdom
+        // and React addendums because they're too noisy.
         if (
-          // Ignore uncaught errors reported by jsdom
-          // and React addendums because they're too noisy.
-          (!logAllErrors &&
-            consoleMethod === 'error' &&
-            shouldIgnoreConsoleError(format, args)) ||
-          // Ignore error objects passed to console.error, which we sometimes
-          // use as a fallback behavior, like when reportError
-          // isn't available.
-          typeof format !== 'string'
+          !logAllErrors &&
+          consoleMethod === 'error' &&
+          shouldIgnoreConsoleError(format, args)
         ) {
           return;
         }