flushSyncWorkAcrossRoots_impl() — react Function Reference

Architecture documentation for the flushSyncWorkAcrossRoots_impl() function in ReactFiberRootScheduler.js from the react codebase.

Function javascript BabelCompiler Validation calls 1 called by 3

Entity Profile

BabelCompiler→ Validation→ flushSyncWorkAcrossRoots_impl() — react Function Reference

Dependency Diagram

graph TD
  b696b90a_5e97_f015_c2fa_f3bf0b69c0d2["flushSyncWorkAcrossRoots_impl()"]
  a22f22c8_f97a_86c8_be5a_4b91a6a21eab["ReactFiberRootScheduler.js"]
  b696b90a_5e97_f015_c2fa_f3bf0b69c0d2 -->|defined in| a22f22c8_f97a_86c8_be5a_4b91a6a21eab
  d39759e1_0993_8c5e_d6fb_971e55a17e03["flushSyncWorkOnAllRoots()"]
  d39759e1_0993_8c5e_d6fb_971e55a17e03 -->|calls| b696b90a_5e97_f015_c2fa_f3bf0b69c0d2
  b695f033_78f9_2acd_a914_48242065304f["flushSyncWorkOnLegacyRootsOnly()"]
  b695f033_78f9_2acd_a914_48242065304f -->|calls| b696b90a_5e97_f015_c2fa_f3bf0b69c0d2
  5e2a5e7b_8a85_c79d_5890_361c5a869d24["processRootScheduleInMicrotask()"]
  5e2a5e7b_8a85_c79d_5890_361c5a869d24 -->|calls| b696b90a_5e97_f015_c2fa_f3bf0b69c0d2
  9070656a_aeba_28ff_4921_4bcb0225f5c1["performSyncWorkOnRoot()"]
  b696b90a_5e97_f015_c2fa_f3bf0b69c0d2 -->|calls| 9070656a_aeba_28ff_4921_4bcb0225f5c1
  style b696b90a_5e97_f015_c2fa_f3bf0b69c0d2 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

packages/react-reconciler/src/ReactFiberRootScheduler.js lines 185–247

function flushSyncWorkAcrossRoots_impl(
  syncTransitionLanes: Lanes | Lane,
  onlyLegacy: boolean,
) {
  if (isFlushingWork) {
    // Prevent reentrancy.
    // TODO: Is this overly defensive? The callers must check the execution
    // context first regardless.
    return;
  }

  if (!mightHavePendingSyncWork) {
    // Fast path. There's no sync work to do.
    return;
  }

  // There may or may not be synchronous work scheduled. Let's check.
  let didPerformSomeWork;
  isFlushingWork = true;
  do {
    didPerformSomeWork = false;
    let root = firstScheduledRoot;
    while (root !== null) {
      if (onlyLegacy && (disableLegacyMode || root.tag !== LegacyRoot)) {
        // Skip non-legacy roots.
      } else {
        if (syncTransitionLanes !== NoLanes) {
          const nextLanes = getNextLanesToFlushSync(root, syncTransitionLanes);
          if (nextLanes !== NoLanes) {
            // This root has pending sync work. Flush it now.
            didPerformSomeWork = true;
            performSyncWorkOnRoot(root, nextLanes);
          }
        } else {
          const workInProgressRoot = getWorkInProgressRoot();
          const workInProgressRootRenderLanes =
            getWorkInProgressRootRenderLanes();
          const rootHasPendingCommit =
            root.cancelPendingCommit !== null ||
            root.timeoutHandle !== noTimeout;
          const nextLanes = getNextLanes(
            root,
            root === workInProgressRoot
              ? workInProgressRootRenderLanes
              : NoLanes,
            rootHasPendingCommit,
          );
          if (
            (includesSyncLane(nextLanes) ||
              (enableGestureTransition && isGestureRender(nextLanes))) &&
            !checkIfRootIsPrerendering(root, nextLanes)
          ) {
            // This root has pending sync work. Flush it now.
            didPerformSomeWork = true;
            performSyncWorkOnRoot(root, nextLanes);
          }
        }
      }
      root = root.next;
    }
  } while (didPerformSomeWork);
  isFlushingWork = false;
}