Function flushCompletedBoundary

packages/react-server/src/ReactFizzServer.js:5868–5903

(
  request: Request,
  destination: Destination,
  boundary: SuspenseBoundary,
)

}

function flushCompletedBoundary(
  request: Request,
  destination: Destination,
  boundary: SuspenseBoundary,
): boolean {
  flushedByteSize = boundary.byteSize; // Start counting bytes
  const completedSegments = boundary.completedSegments;
  let i = 0;
  for (; i < completedSegments.length; i++) {
    const segment = completedSegments[i];
    flushPartiallyCompletedSegment(request, destination, boundary, segment);
  }
  completedSegments.length = 0;

  const row = boundary.row;
  if (row !== null && isEligibleForOutlining(request, boundary)) {
    // Once we have written the boundary, we can unblock the row and let future
    // rows be written. This may schedule new completed boundaries.
    if (--row.pendingTasks === 0) {
      finishSuspenseListRow(request, row);
    }
  }

  writeHoistablesForBoundary(
    destination,
    boundary.contentState,
    request.renderState,
  );
  return writeCompletedBoundaryInstruction(
    destination,
    request.resumableState,
    request.renderState,
    boundary.rootSegmentID,
    boundary.contentState,
  );
}

function flushPartialBoundary(
  request: Request,