checkDirty method

bool checkDirty(Link theLink, ReactiveNode sub)

Checks if a node is dirty and needs updating.

Parameters:

• theLink: The link to check
• sub: The subscriber node

Returns: true if the node is dirty and needs updating

Implementation

bool checkDirty(Link theLink, ReactiveNode sub) {
  Link? link = theLink;
  Stack<Link?>? stack;
  int checkDepth = 0;
  bool dirty = false;

  top:
  do {
    final dep = link!.dep;
    final flags = dep.flags;

    if (sub.flags & 16 /** ReactiveFlags.dirty */ == 16) {
      dirty = true;
    } else if (flags &
            17 /** ReactiveFlags.mutable | ReactiveFlags.dirty */ ==
        17) {
      if (update(dep)) {
        final subs = dep.subs!;
        if (subs.nextSub != null) {
          shallowPropagate(subs);
        }
        dirty = true;
      }
    } else if (flags &
            33 /** ReactiveFlags.mutable | ReactiveFlags.pending */ ==
        33) {
      if (link.nextSub != null || link.prevSub != null) {
        stack = Stack(value: link, prev: stack);
      }
      link = dep.deps!;
      sub = dep;
      ++checkDepth;
      continue;
    }

    if (!dirty) {
      final nextDep = link.nextDep;
      if (nextDep != null) {
        link = nextDep;
        continue;
      }
    }

    while (checkDepth-- != 0) {
      final firstSub = sub.subs!;
      final hasMultipleSubs = firstSub.nextSub != null;
      if (hasMultipleSubs) {
        link = stack!.value;
        stack = stack.prev;
      } else {
        link = firstSub;
      }
      if (dirty) {
        if (update(sub)) {
          if (hasMultipleSubs) {
            shallowPropagate(firstSub);
          }
          sub = link!.sub;
          continue;
        }
        dirty = false;
      } else {
        sub.flags &= ~32 /* ReactiveFlags.pending */;
      }
      sub = link!.sub;
      final nextDep = link.nextDep;
      if (nextDep != null) {
        link = nextDep;
        continue top;
      }
    }

    return dirty;
  } while (true);
}