static void stack_node_add_link()

in lib/src/stack.c [171:228]

• 47 lines of code
• 15 McCabe index (conditional complexity)

static void stack_node_add_link(StackNode *self, StackLink link, SubtreePool *subtree_pool) {
  if (link.node == self) return;

  for (int i = 0; i < self->link_count; i++) {
    StackLink *existing_link = &self->links[i];
    if (stack__subtree_is_equivalent(existing_link->subtree, link.subtree)) {
      // In general, we preserve ambiguities until they are removed from the stack
      // during a pop operation where multiple paths lead to the same node. But in
      // the special case where two links directly connect the same pair of nodes,
      // we can safely remove the ambiguity ahead of time without changing behavior.
      if (existing_link->node == link.node) {
        if (
          ts_subtree_dynamic_precedence(link.subtree) >
          ts_subtree_dynamic_precedence(existing_link->subtree)
        ) {
          ts_subtree_retain(link.subtree);
          ts_subtree_release(subtree_pool, existing_link->subtree);
          existing_link->subtree = link.subtree;
          self->dynamic_precedence =
            link.node->dynamic_precedence + ts_subtree_dynamic_precedence(link.subtree);
        }
        return;
      }

      // If the previous nodes are mergeable, merge them recursively.
      if (existing_link->node->state == link.node->state &&
          existing_link->node->position.bytes == link.node->position.bytes) {
        for (int j = 0; j < link.node->link_count; j++) {
          stack_node_add_link(existing_link->node, link.node->links[j], subtree_pool);
        }
        int32_t dynamic_precedence = link.node->dynamic_precedence;
        if (link.subtree.ptr) {
          dynamic_precedence += ts_subtree_dynamic_precedence(link.subtree);
        }
        if (dynamic_precedence > self->dynamic_precedence) {
          self->dynamic_precedence = dynamic_precedence;
        }
        return;
      }
    }
  }

  if (self->link_count == MAX_LINK_COUNT) return;

  stack_node_retain(link.node);
  unsigned node_count = link.node->node_count;
  int dynamic_precedence = link.node->dynamic_precedence;
  self->links[self->link_count++] = link;

  if (link.subtree.ptr) {
    ts_subtree_retain(link.subtree);
    node_count += ts_subtree_node_count(link.subtree);
    dynamic_precedence += ts_subtree_dynamic_precedence(link.subtree);
  }

  if (node_count > self->node_count) self->node_count = node_count;
  if (dynamic_precedence > self->dynamic_precedence) self->dynamic_precedence = dynamic_precedence;
}