helps to calculate new root of a huge trie after changing few nodes without loading the entire trie.

use partial_mpt::StateTrie;

// create a new trie
let mut state_trie = StateTrie::from_root(block.state_root);

// load proofs for keys to change
state_trie.load_proof(provider.get_proof(address, vec![slot], block.num))

// set value for the key, would give error if proof is not loaded already
state_trie.set_storage_value(address, slot, new_value)

// new root
state_trie.root()

• eth burn
• mainnet block

to run the example, clone this project and cargo run --example eth-burn.

• to run local tests use cargo test
• to run specific tests e.g. cargo test trie::tests::test_node_data
• to run all tests including live mainnet block tests use RPC="https://eth-mainnet.url" cargo test --features test-live

mainnet fork clients do not calculate state root since it's hardly required in smart contract development. but in a recent hackathon, i had to write a chunk of this code in a hurry. just seperating it out for convenience along with some bug fixes and more tests.

MIT