propagateSuspenseContextChange() — react Function Reference

Source Code

packages/react-reconciler/src/ReactFiberBeginWork.js lines 3174–3216

function propagateSuspenseContextChange(
  workInProgress: Fiber,
  firstChild: null | Fiber,
  renderLanes: Lanes,
): void {
  // Mark any Suspense boundaries with fallbacks as having work to do.
  // If they were previously forced into fallbacks, they may now be able
  // to unblock.
  let node = firstChild;
  while (node !== null) {
    if (node.tag === SuspenseComponent) {
      const state: SuspenseState | null = node.memoizedState;
      if (state !== null) {
        scheduleSuspenseWorkOnFiber(node, renderLanes, workInProgress);
      }
    } else if (node.tag === SuspenseListComponent) {
      // If the tail is hidden there might not be an Suspense boundaries
      // to schedule work on. In this case we have to schedule it on the
      // list itself.
      // We don't have to traverse to the children of the list since
      // the list will propagate the change when it rerenders.
      scheduleSuspenseWorkOnFiber(node, renderLanes, workInProgress);
    } else if (node.child !== null) {
      node.child.return = node;
      node = node.child;
      continue;
    }
    if (node === workInProgress) {
      return;
    }
    // $FlowFixMe[incompatible-use] found when upgrading Flow
    while (node.sibling === null) {
      // $FlowFixMe[incompatible-use] found when upgrading Flow
      if (node.return === null || node.return === workInProgress) {
        return;
      }
      node = node.return;
    }
    // $FlowFixMe[incompatible-use] found when upgrading Flow
    node.sibling.return = node.return;
    node = node.sibling;
  }
}