merkletree-rs/src/lib.rs

#[macro_use]
extern crate arrayref;
extern crate hex;
extern crate rustc_hex;
extern crate tiny_keccak;

use rustc_hex::ToHex;

pub mod constants;
pub mod db;
pub mod node;
pub mod utils;

type Result<T> = std::result::Result<T, String>;

pub struct TestValue {
    pub bytes: Vec<u8>,
    pub index_length: u32,
}
pub trait Value {
    fn bytes(&self) -> &Vec<u8>;
    fn index_length(&self) -> u32;
    fn hi(&self) -> [u8; 32];
    fn ht(&self) -> [u8; 32];
}
impl Value for TestValue {
    fn bytes(&self) -> &Vec<u8> {
        &self.bytes
    }
    fn index_length(&self) -> u32 {
        self.index_length
    }
    fn hi(&self) -> [u8; 32] {
        utils::hash_vec(
            self.bytes()
                .to_vec()
                .split_at(self.index_length() as usize)
                .0
                .to_vec(),
        )
    }
    fn ht(&self) -> [u8; 32] {
        utils::hash_vec(self.bytes().to_vec())
    }
}

pub struct MerkleTree<'a> {
    root: [u8; 32],
    num_levels: u32,
    sto: &'a mut db::Db,
    root_node_key: [u8;32],
}
impl<'a> MerkleTree<'a> {
    pub fn new(database: &'a mut db::Db, num_levels: u32) -> MerkleTree<'a> {
        let rnk: [u8; 32] = utils::hash_vec("root".as_bytes().to_vec());
        let (_, _, root_vec) = database.get(&rnk);
        let mut root: [u8; 32] = [0;32];
        root.copy_from_slice(&root_vec); // root will be [0;32] if not found (EMPTYNODEVALUE)

        MerkleTree {
            root: root,
            num_levels,
            sto: database,
            root_node_key: rnk,
        }
    }
    pub fn get_root(&mut self) -> [u8; 32] {
        self.root
    }
    pub fn get_num_levels(&mut self) -> u32 {
        self.num_levels
    }

    pub fn add(&mut self, v: &TestValue) -> Result<()> {
        // add the leaf that we are adding
        self.sto.insert(
            v.ht(),
            constants::TYPENODEVALUE,
            v.index_length(),
            v.bytes().to_vec(),
        );

        let hi = v.hi();
        let path = utils::get_path(self.num_levels, hi);
        let mut siblings: Vec<[u8; 32]> = Vec::new();

        let mut node_hash = self.root;

        for i in (0..=self.num_levels - 2).rev() {
            // get node
            let (t, il, node_bytes) = self.sto.get(&node_hash);
            if t == constants::TYPENODEFINAL {
                let hi_child =
                    utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
                let path_child = utils::get_path(self.num_levels, hi_child);
                let pos_diff = utils::compare_paths(&path_child, &path);
                if pos_diff == -1 {
                    return Err("node already exists".to_owned());
                }
                let final_node_1_hash = utils::calc_hash_from_leaf_and_level(
                    pos_diff as u32,
                    &path_child,
                    utils::hash_vec(node_bytes.to_vec()),
                );
                self.sto.insert(
                    final_node_1_hash,
                    constants::TYPENODEFINAL,
                    il,
                    node_bytes.to_vec(),
                );
                let final_node_2_hash =
                    utils::calc_hash_from_leaf_and_level(pos_diff as u32, &path, v.ht());
                self.sto.insert(
                    final_node_2_hash,
                    constants::TYPENODEFINAL,
                    v.index_length(),
                    v.bytes().to_vec(),
                );

                // parent node
                let parent_node: node::TreeNode;
                if path[pos_diff as usize] {
                    parent_node = node::TreeNode {
                        child_l: final_node_1_hash,
                        child_r: final_node_2_hash,
                    }
                } else {
                    parent_node = node::TreeNode {
                        child_l: final_node_2_hash,
                        child_r: final_node_1_hash,
                    }
                }
                let empties = utils::get_empties_between_i_and_pos(i, pos_diff as u32 + 1);
                for empty in &empties {
                    siblings.push(*empty);
                }

                let path_from_pos_diff = utils::cut_path(&path, (pos_diff + 1) as usize);

                self.root = self.replace_leaf(
                    path_from_pos_diff,
                    &siblings,
                    parent_node.ht(),
                    constants::TYPENODENORMAL,
                    0,
                    parent_node.bytes().to_vec(),
                );
                self.sto
                    .insert(self.root_node_key, constants::TYPENODEROOT, 0, self.root.to_vec());
                return Ok(());
            }

            let node = node::parse_node_bytes(node_bytes);

            let sibling: [u8; 32];
            if !path[i as usize] {
                node_hash = node.child_l;
                sibling = node.child_r;
            } else {
                sibling = node.child_l;
                node_hash = node.child_r;
            }
            siblings.push(*array_ref!(sibling, 0, 32));
            if node_hash == constants::EMPTYNODEVALUE {
                if i == self.num_levels - 2
                    && siblings[siblings.len() - 1] == constants::EMPTYNODEVALUE
                {
                    let final_node_hash =
                        utils::calc_hash_from_leaf_and_level(i + 1, &path, v.ht());
                    self.sto.insert(
                        final_node_hash,
                        constants::TYPENODEFINAL,
                        v.index_length(),
                        v.bytes().to_vec(),
                    );
                    self.root = final_node_hash;
                    self.sto
                        .insert(self.root_node_key, constants::TYPENODEROOT, 0, self.root.to_vec());
                    return Ok(());
                }
                let final_node_hash = utils::calc_hash_from_leaf_and_level(i, &path, v.ht());
                let path_from_i = utils::cut_path(&path, i as usize);
                self.root = self.replace_leaf(
                    path_from_i,
                    &siblings,
                    final_node_hash,
                    constants::TYPENODEFINAL,
                    v.index_length(),
                    v.bytes().to_vec(),
                );
                self.sto
                    .insert(self.root_node_key, constants::TYPENODEROOT, 0, self.root.to_vec());
                return Ok(());
            }
        }
        self.root = self.replace_leaf(
            path,
            &siblings,
            v.ht(),
            constants::TYPENODEVALUE,
            v.index_length(),
            v.bytes().to_vec(),
        );
        self.sto
            .insert(self.root_node_key, constants::TYPENODEROOT, 0, self.root.to_vec());
        return Ok(());
    }

    pub fn replace_leaf(
        &mut self,
        path: Vec<bool>,
        siblings: &Vec<[u8; 32]>,
        leaf_hash: [u8; 32],
        node_type: u8,
        index_length: u32,
        leaf_value: Vec<u8>,
    ) -> [u8; 32] {
        self.sto
            .insert(leaf_hash, node_type, index_length, leaf_value);
        let mut curr_node = leaf_hash;

        for i in 0..siblings.len() {
            if !path[i as usize] {
                let node = node::TreeNode {
                    child_l: curr_node,
                    child_r: siblings[siblings.len() - 1 - i],
                };
                self.sto
                    .insert(node.ht(), constants::TYPENODENORMAL, 0, node.bytes());
                curr_node = node.ht();
            } else {
                let node = node::TreeNode {
                    child_l: siblings[siblings.len() - 1 - i],
                    child_r: curr_node,
                };
                self.sto
                    .insert(node.ht(), constants::TYPENODENORMAL, 0, node.bytes());
                curr_node = node.ht();
            }
        }
        curr_node
    }

    pub fn get_value_in_pos(&mut self, hi: [u8; 32]) -> Vec<u8> {
        let path = utils::get_path(self.num_levels, hi);
        let mut node_hash = self.root;
        for i in (0..=self.num_levels - 2).rev() {
            let (t, il, node_bytes) = self.sto.get(&node_hash);
            if t == constants::TYPENODEFINAL {
                let hi_node = utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
                let path_node = utils::get_path(self.num_levels, hi_node);
                let pos_diff = utils::compare_paths(&path_node, &path);
                if pos_diff != -1 {
                    return constants::EMPTYNODEVALUE.to_vec();
                }
                return node_bytes;
            }
            let node = node::parse_node_bytes(node_bytes);
            if !path[i as usize] {
                node_hash = node.child_l;
            } else {
                node_hash = node.child_r;
            }
        }
        let (_t, _il, node_bytes) = self.sto.get(&node_hash);
        node_bytes
    }

    pub fn generate_proof(&mut self, hi: [u8; 32]) -> Vec<u8> {
        let mut mp: Vec<u8> = Vec::new();

        let mut empties: [u8; 32] = [0; 32];
        let path = utils::get_path(self.num_levels, hi);

        let mut siblings: Vec<[u8; 32]> = Vec::new();
        let mut node_hash = self.root;

        for i in 0..self.num_levels {
            let (t, il, node_bytes) = self.sto.get(&node_hash);
            if t == constants::TYPENODEFINAL {
                let real_value_in_pos = self.get_value_in_pos(hi);
                if real_value_in_pos == constants::EMPTYNODEVALUE {
                    let leaf_hi =
                        utils::hash_vec(node_bytes.to_vec().split_at(il as usize).0.to_vec());
                    let path_child = utils::get_path(self.num_levels, leaf_hi);
                    let pos_diff = utils::compare_paths(&path_child, &path);
                    if pos_diff as u32 == self.num_levels {
                        return mp;
                    }
                    if pos_diff as u32 != self.num_levels - 1 - i {
                        let sibling = utils::calc_hash_from_leaf_and_level(
                            pos_diff as u32,
                            &path_child,
                            utils::hash_vec(node_bytes.to_vec()),
                        );
                        let mut new_siblings: Vec<[u8; 32]> = Vec::new();
                        new_siblings.push(sibling);
                        new_siblings.extend(siblings);
                        siblings = new_siblings;
                        // set empties bit
                        let bit_pos = self.num_levels - 2 - pos_diff as u32;
                        empties[(empties.len() as isize + (bit_pos as isize / 8 - 1) as isize)
                            as usize] |= 1 << (bit_pos % 8);
                    }
                }
                break;
            }
            let node = node::parse_node_bytes(node_bytes);
            let sibling: [u8; 32];
            if !path[self.num_levels as usize - i as usize - 2] {
                node_hash = node.child_l;
                sibling = node.child_r;
            } else {
                sibling = node.child_l;
                node_hash = node.child_r;
            }
            if sibling != constants::EMPTYNODEVALUE {
                // set empties bit
                empties[(empties.len() as isize + (i as isize / 8 - 1) as isize) as usize] |=
                    1 << (i % 8);
                let mut new_siblings: Vec<[u8; 32]> = Vec::new();
                new_siblings.push(sibling);
                new_siblings.extend(siblings);
                siblings = new_siblings;
            }
        }
        mp.append(&mut empties[..].to_vec());
        for s in siblings {
            mp.append(&mut s.to_vec());
        }
        mp
    }

    pub fn print_level(&mut self, parent: [u8; 32], mut lvl: u32, max_level: u32) {
        let mut line: String = "".to_string();
        for _ in 0..lvl {
            line += &format!(" ");
        }
        line += &format!("lvl {}", lvl);
        line += &format!(" - '{}'  = ", parent.to_hex());
        let (t, _, node_bytes) = self.sto.get(&parent);
        let mut node = node::TreeNode {
            child_l: constants::EMPTYNODEVALUE,
            child_r: constants::EMPTYNODEVALUE,
        };
        if t == constants::TYPENODENORMAL {
            node = node::parse_node_bytes(node_bytes);
            line += &format!("'{}' - '{}'", node.child_l.to_hex(), node.child_r.to_hex());
        } else if t == constants::TYPENODEVALUE {
            //
        } else if t == constants::TYPENODEFINAL {
            let hash_node_bytes = utils::hash_vec(node_bytes);
            line += &format!("[final] final tree node: {} \n", hash_node_bytes.to_hex());
            let (_, _, leaf_node_bytes) = self.sto.get(&hash_node_bytes);
            for _ in 0..lvl {
                line += "  ";
            }
            let leaf_node_string = String::from_utf8_lossy(&leaf_node_bytes);
            line += &format!("leaf value: {}", leaf_node_string);
        } else {
            line += "[EMPTY Branch]"
        }
        println!("{}", line);
        lvl += 1;
        if node.child_r.len() > 0
            && lvl < max_level
            && t != constants::TYPENODEEMPTY
            && t != constants::TYPENODEFINAL
        {
            self.print_level(node.child_l, lvl, max_level);
            self.print_level(node.child_r, lvl, max_level);
        }
    }
    pub fn print_full_tree(&mut self) {
        let root = self.root.clone();
        let num_levels = self.num_levels.clone();
        self.print_level(root, 0, num_levels - 1);
        println!("root {:?}", &self.root.to_hex());
    }
    pub fn print_levels_tree(&mut self, max_level: u32) {
        let root = self.root.clone();
        let num_levels = self.num_levels.clone();
        self.print_level(root, 0, num_levels - 1 - max_level);
        println!("root {:?}", self.root.to_hex());
    }
}

pub fn verify_proof(
    root: [u8; 32],
    mp: &Vec<u8>,
    hi: [u8; 32],
    ht: [u8; 32],
    num_levels: u32,
) -> bool {
    let empties: Vec<u8>;
    empties = mp.split_at(32).0.to_vec();

    let mut siblings: Vec<[u8; 32]> = Vec::new();
    for i in (empties.len()..mp.len()).step_by(constants::EMPTYNODEVALUE.len()) {
        let mut sibling: [u8; 32] = [0; 32];
        sibling.copy_from_slice(&mp[i..i + constants::EMPTYNODEVALUE.len()]);
        siblings.push(sibling);
    }

    let path = utils::get_path(num_levels, hi);
    let mut node_hash = ht;
    let mut sibling_used_pos = 0;

    for i in (0..=num_levels - 2).rev() {
        let sibling: [u8; 32];
        if (empties[empties.len() - i as usize / 8 - 1] & (1 << (i % 8))) > 0 {
            sibling = siblings[sibling_used_pos];
            sibling_used_pos += 1;
        } else {
            sibling = constants::EMPTYNODEVALUE;
        }

        let n: node::TreeNode;
        if path[num_levels as usize - i as usize - 2] {
            n = node::TreeNode {
                child_l: sibling,
                child_r: node_hash,
            }
        } else {
            n = node::TreeNode {
                child_l: node_hash,
                child_r: sibling,
            }
        }
        if node_hash == constants::EMPTYNODEVALUE && sibling == constants::EMPTYNODEVALUE {
            node_hash = constants::EMPTYNODEVALUE;
        } else {
            node_hash = n.ht();
        }
    }
    if node_hash == root {
        return true;
    }
    false
}

#[cfg(test)]
mod tests {
    use super::*;
    use rustc_hex::ToHex;

    #[test]
    fn test_hash_vec() {
        let a: Vec<u8> = From::from("test".to_string());
        let h = utils::hash_vec(a);
        assert_eq!(
            "9c22ff5f21f0b81b113e63f7db6da94fedef11b2119b4088b89664fb9a3cb658",
            h.to_hex()
        );
    }

    #[test]
    fn test_new_mt() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mt = MerkleTree::new(&mut sto, 140);
        assert_eq!(140, mt.num_levels);
        assert_eq!(
            "0000000000000000000000000000000000000000000000000000000000000000",
            mt.root.to_hex()
        );
        let (_t, _il, b) = mt.sto.get(&[0; 32]);
        assert_eq!(mt.root.to_vec(), b);
    }

    #[test]
    fn test_tree_node() {
        let n = node::TreeNode {
            child_l: [1; 32],
            child_r: [2; 32],
        };
        assert_eq!("01010101010101010101010101010101010101010101010101010101010101010202020202020202020202020202020202020202020202020202020202020202",
                    n.bytes().to_hex());
        assert_eq!(
            "346d8c96a2454213fcc0daff3c96ad0398148181b9fa6488f7ae2c0af5b20aa0",
            n.ht().to_hex()
        );
    }

    #[test]
    fn test_add() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        assert_eq!(
            "0000000000000000000000000000000000000000000000000000000000000000",
            mt.root.to_hex()
        );
        let val = TestValue {
            bytes: vec![1, 2, 3, 4, 5],
            index_length: 3,
        };
        mt.add(&val).unwrap();
        let (_t, _il, b) = mt.sto.get(&val.ht());
        assert_eq!(*val.bytes(), b);
        assert_eq!(
            "a0e72cc948119fcb71b413cf5ada12b2b825d5133299b20a6d9325ffc3e2fbf1",
            mt.root.to_hex()
        );
    }

    #[test]
    fn test_add_2() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        let val = TestValue {
            bytes: "this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        assert_eq!(
            "0000000000000000000000000000000000000000000000000000000000000000",
            mt.root.to_hex()
        );
        mt.add(&val).unwrap();
        let (_t, _il, b) = mt.sto.get(&val.ht());
        assert_eq!(*val.bytes(), b);
        assert_eq!(
            "b4fdf8a653198f0e179ccb3af7e4fc09d76247f479d6cfc95cd92d6fda589f27",
            mt.root.to_hex()
        );
        let val2 = TestValue {
            bytes: "this is a second test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        mt.add(&val2).unwrap();
        let (_t, _il, b) = mt.sto.get(&val2.ht());
        assert_eq!(*val2.bytes(), b);
        assert_eq!(
            "8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82",
            mt.root.to_hex()
        );
    }

    #[test]
    fn test_generate_proof_and_verify_proof() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        let val = TestValue {
            bytes: "this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        assert_eq!(
            "0000000000000000000000000000000000000000000000000000000000000000",
            mt.root.to_hex()
        );
        mt.add(&val).unwrap();
        let (_t, _il, b) = mt.sto.get(&val.ht());
        assert_eq!(*val.bytes(), b);
        assert_eq!(
            "b4fdf8a653198f0e179ccb3af7e4fc09d76247f479d6cfc95cd92d6fda589f27",
            mt.root.to_hex()
        );
        let val2 = TestValue {
            bytes: "this is a second test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        mt.add(&val2).unwrap();
        let (_t, _il, b) = mt.sto.get(&val2.ht());
        assert_eq!(*val2.bytes(), b);
        assert_eq!(
            "8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82",
            mt.root.to_hex()
        );

        let mp = mt.generate_proof(val2.hi());
        assert_eq!("0000000000000000000000000000000000000000000000000000000000000001fd8e1a60cdb23c0c7b2cf8462c99fafd905054dccb0ed75e7c8a7d6806749b6b", mp.to_hex());

        // verify
        let v = verify_proof(mt.root, &mp, val2.hi(), val2.ht(), mt.num_levels);
        assert_eq!(true, v);
    }

    #[test]
    fn test_generate_proof_empty_leaf_and_verify_proof() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        let val = TestValue {
            bytes: "this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        mt.add(&val).unwrap();
        let val2 = TestValue {
            bytes: "this is a second test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        mt.add(&val2).unwrap();
        assert_eq!(
            "8ac95e9c8a6fbd40bb21de7895ee35f9c8f30ca029dbb0972c02344f49462e82",
            mt.root.to_hex()
        );

        // proof of empty leaf
        let val3 = TestValue {
            bytes: "this is a third test leaf".as_bytes().to_vec(),
            index_length: 15,
        };
        let mp = mt.generate_proof(val3.hi());
        assert_eq!("000000000000000000000000000000000000000000000000000000000000000389741fa23da77c259781ad8f4331a5a7d793eef1db7e5200ddfc8e5f5ca7ce2bfd8e1a60cdb23c0c7b2cf8462c99fafd905054dccb0ed75e7c8a7d6806749b6b", mp.to_hex());

        // verify that is a proof of an empty leaf (constants::EMPTYNODEVALUE)
        let v = verify_proof(
            mt.root,
            &mp,
            val3.hi(),
            constants::EMPTYNODEVALUE,
            mt.num_levels,
        );
        assert_eq!(true, v);
    }

    #[test]
    fn test_harcoded_proofs_of_existing_leaf() {
        // check proof of value in leaf
        let mut root: [u8; 32] = [0; 32];
        root.copy_from_slice(
            &hex::decode("7d7c5e8f4b3bf434f3d9d223359c4415e2764dd38de2e025fbf986e976a7ed3d")
                .unwrap(),
        );
        let mp = hex::decode("0000000000000000000000000000000000000000000000000000000000000002d45aada6eec346222eaa6b5d3a9260e08c9b62fcf63c72bc05df284de07e6a52").unwrap();
        let mut hi: [u8; 32] = [0; 32];
        hi.copy_from_slice(
            &hex::decode("786677808ba77bdd9090a969f1ef2cbd1ac5aecd9e654f340500159219106878")
                .unwrap(),
        );
        let mut ht: [u8; 32] = [0; 32];
        ht.copy_from_slice(
            &hex::decode("786677808ba77bdd9090a969f1ef2cbd1ac5aecd9e654f340500159219106878")
                .unwrap(),
        );
        let v = verify_proof(root, &mp, hi, ht, 140);
        assert_eq!(true, v);
    }

    #[test]
    fn test_harcoded_proofs_of_empty_leaf() {
        // check proof of value in leaf
        let mut root: [u8; 32] = [0; 32];
        root.copy_from_slice(
            &hex::decode("8f021d00c39dcd768974ddfe0d21f5d13f7215bea28db1f1cb29842b111332e7")
                .unwrap(),
        );
        let mp = hex::decode("0000000000000000000000000000000000000000000000000000000000000004bf8e980d2ed328ae97f65c30c25520aeb53ff837579e392ea1464934c7c1feb9").unwrap();
        let mut hi: [u8; 32] = [0; 32];
        hi.copy_from_slice(
            &hex::decode("a69792a4cff51f40b7a1f7ae596c6ded4aba241646a47538898f17f2a8dff647")
                .unwrap(),
        );
        let v = verify_proof(root, &mp, hi, constants::EMPTYNODEVALUE, 140);
        assert_eq!(true, v);
    }

    #[test]
    fn test_add_leafs_different_order() {
        let mut sto1 = db::Db::new("test".to_string(), true);
        let mut mt1 = MerkleTree::new(&mut sto1, 140);
        mt1.add(&TestValue {
            bytes: "0 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt1.add(&TestValue {
            bytes: "1 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt1.add(&TestValue {
            bytes: "2 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt1.add(&TestValue {
            bytes: "3 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt1.add(&TestValue {
            bytes: "4 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt1.add(&TestValue {
            bytes: "5 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        // mt1.print_full_tree();

        let mut sto2 = db::Db::new("test".to_string(), true);
        let mut mt2 = MerkleTree::new(&mut sto2, 140);
        mt2.add(&TestValue {
            bytes: "2 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt2.add(&TestValue {
            bytes: "1 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt2.add(&TestValue {
            bytes: "0 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt2.add(&TestValue {
            bytes: "5 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt2.add(&TestValue {
            bytes: "3 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        mt2.add(&TestValue {
            bytes: "4 this is a test leaf".as_bytes().to_vec(),
            index_length: 15,
        })
        .unwrap();
        // mt2.print_full_tree();

        assert_eq!(mt1.root, mt2.root);
        assert_eq!(
            &mt1.root.to_hex(),
            "264397f84da141b3134dcde1d7540d27a2bf0d787bbe8365d9ad5c9c18d3c621"
        );
    }

    #[test]
    fn test_add_1000_leafs() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        for i in 0..1000 {
            mt.add(&TestValue {
                bytes: (i.to_string() + " this is a test leaf").as_bytes().to_vec(),
                index_length: 15,
            })
            .unwrap();
        }
        assert_eq!(
            mt.root.to_hex(),
            "6e2da580b2920cd78ed8d4e4bf41e209dfc99ef28bc19560042f0ac803e0d6f7"
        );
    }

    #[test]
    fn test_get_root_in_db() {
        let mut sto = db::Db::new("test".to_string(), true);
        let mut mt = MerkleTree::new(&mut sto, 140);
        for i in 0..10 {
            mt.add(&TestValue {
                bytes: (i.to_string() + " this is a test leaf").as_bytes().to_vec(),
                index_length: 15,
            })
            .unwrap();
        }
        assert_eq!(
            mt.root.to_hex(),
            "9418fd35bae19de4ab033efaf7cc624adf6a42827e39029d8da13288e9c3170d"
        );
        let mt2 = MerkleTree::new(&mut sto, 140);
        assert_eq!(
            mt2.root.to_hex(),
            "9418fd35bae19de4ab033efaf7cc624adf6a42827e39029d8da13288e9c3170d"
        );
    }
}