use hex_literal::hex; use pmtree::*; use std::collections::HashMap; use tiny_keccak::{Hasher as _, Keccak}; struct MemoryDB(HashMap); struct MyKeccak(Keccak); #[derive(Clone, Copy, Debug, Default, PartialEq, Eq)] struct MyFr([u8; 32]); impl Database for MemoryDB { fn new(_dbpath: &str) -> Result { Ok(MemoryDB(HashMap::new())) } fn load(_dbpath: &str) -> Result { Err(Error("Cannot load in-memory DB".to_string())) } fn get(&self, key: DBKey) -> Result> { Ok(self.0.get(&key).cloned()) } fn put(&mut self, key: DBKey, value: Value) -> Result<()> { self.0.insert(key, value); Ok(()) } } impl From> for MyFr { fn from(v: Vec) -> Self { let v = v.try_into().unwrap(); MyFr(v) } } impl From for Vec { fn from(v: MyFr) -> Self { v.0.to_vec() } } impl Hasher for MyKeccak { type Fr = MyFr; fn default_leaf() -> Self::Fr { MyFr([0; 32]) } fn hash(input: &[Self::Fr]) -> Self::Fr { let mut output = [0; 32]; let mut hasher = Keccak::v256(); for element in input { hasher.update(&element.0); } hasher.finalize(&mut output); MyFr(output) } } #[test] fn insert_delete() -> Result<()> { let mut mt = MerkleTree::::new(2, "abacaba")?; assert_eq!(mt.capacity(), 4); assert_eq!(mt.depth(), 2); let leaves = [ hex!("0000000000000000000000000000000000000000000000000000000000000001"), hex!("0000000000000000000000000000000000000000000000000000000000000002"), hex!("0000000000000000000000000000000000000000000000000000000000000003"), hex!("0000000000000000000000000000000000000000000000000000000000000004"), ]; let default_tree_root = hex!("b4c11951957c6f8f642c4af61cd6b24640fec6dc7fc607ee8206a99e92410d30"); assert_eq!(mt.root()?, MyFr(default_tree_root)); let roots = [ hex!("c1ba1812ff680ce84c1d5b4f1087eeb08147a4d510f3496b2849df3a73f5af95"), hex!("893760ec5b5bee236f29e85aef64f17139c3c1b7ff24ce64eb6315fca0f2485b"), hex!("222ff5e0b5877792c2bc1670e2ccd0c2c97cd7bb1672a57d598db05092d3d72c"), hex!("a9bb8c3f1f12e9aa903a50c47f314b57610a3ab32f2d463293f58836def38d36"), ]; for i in 0..leaves.len() { mt.update_next(MyFr(leaves[i]))?; assert_eq!(mt.root()?, MyFr(roots[i])); } for i in (0..leaves.len()).rev() { mt.delete(i)?; } assert_eq!(mt.root()?, MyFr(default_tree_root)); assert!(mt.update_next(MyFr(leaves[0])).is_err()); Ok(()) }