solana/core/src/tree_diff.rs

33 lines
1.0 KiB
Rust

use std::{collections::HashSet, hash::Hash};
pub trait TreeDiff {
type TreeKey: Hash + PartialEq + Eq + Copy;
fn children(&self, key: &Self::TreeKey) -> Option<&[Self::TreeKey]>;
fn contains_slot(&self, slot: &Self::TreeKey) -> bool;
// Find all nodes reachable from `root1`, excluding subtree at `root2`
fn subtree_diff(&self, root1: Self::TreeKey, root2: Self::TreeKey) -> HashSet<Self::TreeKey> {
if !self.contains_slot(&root1) {
return HashSet::new();
}
let mut pending_keys = vec![root1];
let mut reachable_set = HashSet::new();
while !pending_keys.is_empty() {
let current_key = pending_keys.pop().unwrap();
if current_key == root2 {
continue;
}
for child in self
.children(&current_key)
.expect("slot was discovered earlier, must exist")
{
pending_keys.push(*child);
}
reachable_set.insert(current_key);
}
reachable_set
}
}