Reconstruction from db and then remove keys will result wrong root hash

[mohanson]

See codes below, I think it should be root1 == root2 == root3, but (root1 == root2) != root3 in fact.

fn main() {
    let root1 = {
        let mut db = cita_trie::db::MemoryDB::new();
        let mut trie = cita_trie::trie::PatriciaTrie::new(&mut db, cita_trie::codec::RLPNodeCodec::default());
        trie.insert(b"a", b"a").unwrap();
        trie.root().unwrap()
    };

    let root2 = {
        let mut db = cita_trie::db::MemoryDB::new();
        let mut trie = cita_trie::trie::PatriciaTrie::new(&mut db, cita_trie::codec::RLPNodeCodec::default());
        trie.insert(b"a", b"a").unwrap();
        trie.insert(b"b", b"b").unwrap();
        trie.root().unwrap();
        trie.remove(b"b").unwrap();
        trie.root().unwrap()
    };

    let root3 = {
        let mut db = cita_trie::db::MemoryDB::new();
        let mut t1 = cita_trie::trie::PatriciaTrie::new(&mut db, cita_trie::codec::RLPNodeCodec::default());
        t1.insert(b"a", b"a").unwrap();
        t1.insert(b"b", b"b").unwrap();
        let root = t1.root().unwrap();
        let mut t2 = cita_trie::trie::PatriciaTrie::from(&mut db, cita_trie::codec::RLPNodeCodec::default(), &root).unwrap();
        t2.remove(b"b").unwrap();
        t2.root().unwrap()
    };

    println!("{:?}", hex::encode(root1)); // "668aee9307d4b41714f33b61fd7e0704d31b95e42169292ba56af48929079580"
    println!("{:?}", hex::encode(root2)); // "668aee9307d4b41714f33b61fd7e0704d31b95e42169292ba56af48929079580"
    println!("{:?}", hex::encode(root3)); // "f3313809b6501771b8a698b8c70979f3f8340b4f7e90dc5db96caf81cf5a25e0"
}

[yejiayu]

Is it the latest version？ Also, is this a bug blocking your work？

[mohanson]

1) Is it the latest version Yes. 2) is this a bug blocking your work Yes.

[yejiayu]

emmm, i will fix it as soon as possible