void ts_subtree_balance()

in lib/src/subtree.c [323:356]

• 30 lines of code
• 12 McCabe index (conditional complexity)

void ts_subtree_balance(Subtree self, SubtreePool *pool, const TSLanguage *language) {
  array_clear(&pool->tree_stack);

  if (ts_subtree_child_count(self) > 0 && self.ptr->ref_count == 1) {
    array_push(&pool->tree_stack, ts_subtree_to_mut_unsafe(self));
  }

  while (pool->tree_stack.size > 0) {
    MutableSubtree tree = array_pop(&pool->tree_stack);

    if (tree.ptr->repeat_depth > 0) {
      Subtree child1 = tree.ptr->children[0];
      Subtree child2 = tree.ptr->children[tree.ptr->child_count - 1];
      if (
        ts_subtree_child_count(child1) > 0 &&
        ts_subtree_child_count(child2) > 0 &&
        child1.ptr->repeat_depth > child2.ptr->repeat_depth
      ) {
        unsigned n = child1.ptr->repeat_depth - child2.ptr->repeat_depth;
        for (unsigned i = n / 2; i > 0; i /= 2) {
          ts_subtree__compress(tree, i, language, &pool->tree_stack);
          n -= i;
        }
      }
    }

    for (uint32_t i = 0; i < tree.ptr->child_count; i++) {
      Subtree child = tree.ptr->children[i];
      if (ts_subtree_child_count(child) > 0 && child.ptr->ref_count == 1) {
        array_push(&pool->tree_stack, ts_subtree_to_mut_unsafe(child));
      }
    }
  }
}