- unitOfWork
if (returnFiber !== null && (returnFiber.flags & Incomplete) === NoFlags) {if (returnFiber.firstEffect === null) {returnFiber.firstEffect = completedWork.firstEffect;}
if (completedWork.lastEffect !== null) {if (returnFiber.lastEffect !== null) {returnFiber.lastEffect.nextEffect = completedWork.firstEffect;}
returnFiber.lastEffect = completedWork.lastEffect;
}
var flags = completedWork.flags;
if (flags > PerformedWork) {if (returnFiber.lastEffect !== null) {returnFiber.lastEffect.nextEffect = completedWork;} else {returnFiber.firstEffect = completedWork;}
returnFiber.lastEffect = completedWork;
}
}