Module sparse_merkle_tree 

Sparse Merkle Tree implementation compatible with circomlibjs/smt.js

This is a Rust port of the Sparse Merkle Tree implementation from:

• JavaScript: https://github.com/iden3/circomlibjs/blob/main/src/smt.js

This implementation uses Poseidon2 hash function for compatibility with circomlib circuits.

Structs

FindResult

Find result for internal operations

SMTMemDB

In-memory database implementation Stores every node (leaves and internal nodes) as raw BigInt vectors, matching circomlibjs layout.

SMTProof

Proof data tailored for Circom inputs (BigInt-based).

SMTResult

Result of SMT operations

SparseMerkleTree

Sparse Merkle Tree implementation matching circomlibjs/smt.js Provides insert/update/delete/find helpers that operate entirely over BigInts so test harnesses can generate witnesses identical to the JavaScript reference implementation.

Traits

SMTDatabase

Database trait for SMT storage

Functions

new_mem_empty_trie

Create a new empty SMT with an in-memory database

poseidon2_compression_sparse

Poseidon2 hash of two field elements using optimized compression mode

poseidon2_hash3_sparse

Poseidon2 hash function for leaf nodes (key, value, 1)

prepare_smt_proof

Prepare an SMT proof after pre-populating the tree with values 0..100

prepare_smt_proof_with_overrides

Build a sparse SMT from overrides and return a proof for key. overrides is (key, value) pairs already reduced modulo field.