alloy-eip7928 0.4.11

//! Contains the [`AccountChanges`] struct, which represents storage writes, balance, nonce, code
//! changes and read for the account. All changes for a single account, grouped by field type.
//! This eliminates address redundancy across different change types.

use crate::{
    BalAccountInfo, BlockAccessIndex, SlotChanges, balance_change::BalanceChange,
    code_change::CodeChange, nonce_change::NonceChange,
};
use alloc::vec::Vec;
use alloy_primitives::{
    Address, B256, Bytes, KECCAK256_EMPTY, U256, keccak256,
    map::{HashMap, HashSet},
};

/// This struct is used to track the changes across accounts in a block.
#[derive(Debug, Clone, Default, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "rlp", derive(alloy_rlp::RlpEncodable, alloy_rlp::RlpDecodable))]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[cfg_attr(feature = "borsh", derive(borsh::BorshSerialize, borsh::BorshDeserialize))]
#[cfg_attr(feature = "serde", serde(rename_all = "camelCase"))]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct AccountChanges {
    /// The address of the account whose changes are stored.
    pub address: Address,
    /// List of slot changes for this account.
    pub storage_changes: Vec<SlotChanges>,
    /// List of storage reads for this account.
    pub storage_reads: Vec<U256>,
    /// List of balance changes for this account.
    pub balance_changes: Vec<BalanceChange>,
    /// List of nonce changes for this account.
    pub nonce_changes: Vec<NonceChange>,
    /// List of code changes for this account.
    pub code_changes: Vec<CodeChange>,
}

impl AccountChanges {
    /// Creates a new [`AccountChanges`] instance for the given address with empty vectors.
    pub const fn new(address: Address) -> Self {
        Self {
            address,
            storage_changes: Vec::new(),
            storage_reads: Vec::new(),
            balance_changes: Vec::new(),
            nonce_changes: Vec::new(),
            code_changes: Vec::new(),
        }
    }

    /// Creates a new [`AccountChanges`] instance for the given address with specified capacity.
    pub fn with_capacity(address: Address, capacity: usize) -> Self {
        Self {
            address,
            storage_changes: Vec::with_capacity(capacity),
            storage_reads: Vec::with_capacity(capacity),
            balance_changes: Vec::with_capacity(capacity),
            nonce_changes: Vec::with_capacity(capacity),
            code_changes: Vec::with_capacity(capacity),
        }
    }

    /// Returns the address of the account.
    #[inline]
    pub const fn address(&self) -> Address {
        self.address
    }

    /// Returns `true` if this account change set contains no changes or reads.
    ///
    /// A [`SlotChanges`] entry with an empty change list does not count as data, so an entry
    /// that only carries the address (or empty slot entries) is considered empty.
    pub fn is_empty(&self) -> bool {
        let Self {
            address: _,
            storage_changes,
            storage_reads,
            balance_changes,
            nonce_changes,
            code_changes,
        } = self;
        storage_changes.iter().all(SlotChanges::is_empty)
            && storage_reads.is_empty()
            && balance_changes.is_empty()
            && nonce_changes.is_empty()
            && code_changes.is_empty()
    }

    /// Returns the storage changes for this account.
    #[inline]
    pub fn storage_changes(&self) -> &[SlotChanges] {
        &self.storage_changes
    }

    /// Returns an iterator over storage slots present in this account's changes and reads.
    ///
    /// Changed slots are yielded first, followed by read slots.
    #[inline]
    pub fn storage_slots(&self) -> impl Iterator<Item = U256> + '_ {
        self.storage_changes
            .iter()
            .map(|changes| changes.slot)
            .chain(self.storage_reads.iter().copied())
    }

    /// Returns an iterator over the post-state value for each changed storage slot.
    ///
    /// The post-state value is taken from the last recorded change for each slot.
    #[inline]
    pub fn storage_post_states(&self) -> impl Iterator<Item = (U256, U256)> + '_ {
        self.storage_changes.iter().filter_map(|changes| {
            changes.changes.last().map(|change| (changes.slot, change.new_value))
        })
    }

    /// Returns the balance from the last recorded change, or `None` if unchanged.
    #[inline]
    pub fn balance_post_state(&self) -> Option<U256> {
        self.balance_changes.last().map(|change| change.post_balance)
    }

    /// Returns the nonce from the last recorded change, or `None` if unchanged.
    #[inline]
    pub fn nonce_post_state(&self) -> Option<u64> {
        self.nonce_changes.last().map(|change| change.new_nonce)
    }

    /// Returns the code from the last recorded change, or `None` if unchanged.
    #[inline]
    pub fn code_post_state(&self) -> Option<&Bytes> {
        self.code_changes.last().map(|change| &change.new_code)
    }

    /// Returns the hash of the code from the last recorded change, or `None` if unchanged.
    ///
    /// [`KECCAK256_EMPTY`] is returned when the code was set to empty.
    #[inline]
    pub fn code_hash_post_state(&self) -> Option<B256> {
        self.code_post_state().map(|code| code_hash(code))
    }

    /// Returns the code from the last recorded change together with its hash, or `None` if
    /// unchanged.
    ///
    /// Use this over hashing [`Self::code_post_state`] separately when both the code and its hash
    /// are needed, for example when storing the deployed bytecode by hash.
    #[inline]
    pub fn code_post_state_with_hash(&self) -> Option<(B256, &Bytes)> {
        self.code_post_state().map(|code| (code_hash(code), code))
    }

    /// Returns the account-level fields this entry changed, see [`BalAccountInfo`].
    #[inline]
    pub fn account_info(&self) -> BalAccountInfo {
        BalAccountInfo::from_changes(self)
    }

    /// Returns `true` if this entry writes at least one storage slot.
    ///
    /// [`SlotChanges`] entries without changes are ignored, mirroring [`Self::is_empty`].
    pub fn has_storage_changes(&self) -> bool {
        self.storage_changes.iter().any(|changes| !changes.is_empty())
    }

    /// Returns `true` if this entry records at least one state change.
    ///
    /// Entries that only record reads leave the account untouched and do not contribute to the
    /// block's post-state.
    pub fn has_changes(&self) -> bool {
        !self.balance_changes.is_empty()
            || !self.nonce_changes.is_empty()
            || !self.code_changes.is_empty()
            || self.has_storage_changes()
    }

    /// Merges another account change set into this one.
    ///
    /// Storage changes for matching slots are grouped together. Storage reads are normalized after
    /// merging so that written slots are represented by `storage_changes`, while `storage_reads`
    /// only contains unique read-only slots in first-seen order. This preserves the EIP-7928
    /// invariant that a storage slot appears in either reads or changes, but not both, after
    /// independently valid account change sets are combined.
    ///
    /// This preserves relative ordering by appending incoming changes to existing changes. Call
    /// [`Self::sort`] after merging if canonical EIP-7928 ordering is required.
    ///
    /// # Panics
    ///
    /// Panics if the two account change sets have different addresses.
    pub fn merge(&mut self, incoming: Self) {
        assert_eq!(
            self.address, incoming.address,
            "cannot merge account changes for different addresses"
        );

        merge_slot_changes(&mut self.storage_changes, incoming.storage_changes);
        self.storage_reads.extend(incoming.storage_reads);
        self.balance_changes.extend(incoming.balance_changes);
        self.nonce_changes.extend(incoming.nonce_changes);
        self.code_changes.extend(incoming.code_changes);

        let written = self
            .storage_changes
            .iter()
            .map(|slot_changes| slot_changes.slot)
            .collect::<HashSet<_>>();
        self.storage_reads.retain(|slot| !written.contains(slot));

        let mut seen = HashSet::with_capacity(self.storage_reads.len());
        self.storage_reads.retain(|slot| seen.insert(*slot));
    }

    /// Returns the storage reads for this account.
    #[inline]
    pub fn storage_reads(&self) -> &[U256] {
        &self.storage_reads
    }

    /// Returns the balance changes for this account.
    #[inline]
    pub fn balance_changes(&self) -> &[BalanceChange] {
        &self.balance_changes
    }

    /// Returns the nonce changes for this account.
    #[inline]
    pub fn nonce_changes(&self) -> &[NonceChange] {
        &self.nonce_changes
    }

    /// Returns the code changes for this account.
    #[inline]
    pub fn code_changes(&self) -> &[CodeChange] {
        &self.code_changes
    }

    /// Sorts this account's changes in-place according to the account-local EIP-7928 ordering
    /// rules.
    ///
    /// This applies the account-local ordering required by the "Ordering, Uniqueness and
    /// Determinism" section of EIP-7928:
    ///
    /// - `storage_changes` are sorted lexicographically by storage key
    /// - each per-slot `StorageChange` list is sorted by block access index in ascending order
    /// - `storage_reads` are sorted lexicographically by storage key
    /// - `balance_changes`, `nonce_changes`, and `code_changes` are sorted by block access index in
    ///   ascending order
    ///
    /// Per-slot storage change ordering is delegated to [`SlotChanges::sort`].
    ///
    /// This method only canonicalizes ordering for a single account. It does not enforce the
    /// EIP-7928 uniqueness constraints for storage keys or block access indexes.
    pub fn sort(&mut self) {
        self.storage_changes.sort_unstable_by_key(|changes| changes.slot);
        for slot_changes in &mut self.storage_changes {
            slot_changes.sort();
        }

        self.storage_reads.sort_unstable();
        self.balance_changes.sort_unstable_by_key(|change| change.block_access_index);
        self.nonce_changes.sort_unstable_by_key(|change| change.block_access_index);
        self.code_changes.sort_unstable_by_key(|change| change.block_access_index);
    }

    /// Renormalizes this account change set in place.
    ///
    /// Empty [`SlotChanges`] entries are dropped, duplicate slot entries are folded together
    /// (preserving the relative order of their changes), and storage reads are deduplicated and
    /// pruned against written slots, restoring the EIP-7928 invariant that a slot appears in
    /// either reads or changes but not both.
    pub fn normalize(&mut self) {
        self.storage_changes.retain(|slot_changes| !slot_changes.is_empty());
        let incoming = core::mem::replace(self, Self::new(self.address));
        self.merge(incoming);
    }

    /// Collapses each change list to its last entry and assigns that entry to `at`.
    ///
    /// The last entry of each list is treated as the effective value ("last write wins"),
    /// matching [`Self::storage_post_states`]. Storage reads carry no block access index and are
    /// left untouched.
    pub fn collapse_changes_at(&mut self, at: BlockAccessIndex) {
        let Self {
            address: _,
            storage_changes,
            storage_reads: _,
            balance_changes,
            nonce_changes,
            code_changes,
        } = self;
        for slot_changes in storage_changes.iter_mut() {
            keep_last(&mut slot_changes.changes, |change| change.block_access_index = at);
        }
        keep_last(balance_changes, |change| change.block_access_index = at);
        keep_last(nonce_changes, |change| change.block_access_index = at);
        keep_last(code_changes, |change| change.block_access_index = at);
    }

    /// Shifts every recorded block access index at or after `from` forward by one.
    ///
    /// Indices saturate at `u64::MAX` instead of overflowing.
    pub fn shift_indices_from(&mut self, from: BlockAccessIndex) {
        let Self {
            address: _,
            storage_changes,
            storage_reads: _,
            balance_changes,
            nonce_changes,
            code_changes,
        } = self;
        let storage = storage_changes
            .iter_mut()
            .flat_map(|slot_changes| slot_changes.changes.iter_mut())
            .map(|change| &mut change.block_access_index);
        let balances = balance_changes.iter_mut().map(|change| &mut change.block_access_index);
        let nonces = nonce_changes.iter_mut().map(|change| &mut change.block_access_index);
        let codes = code_changes.iter_mut().map(|change| &mut change.block_access_index);
        for index in storage.chain(balances).chain(nonces).chain(codes) {
            if *index >= from {
                index.saturating_increment();
            }
        }
    }

    /// Set the address.
    pub const fn with_address(mut self, address: Address) -> Self {
        self.address = address;
        self
    }

    /// Add a storage read slot.
    pub fn with_storage_read(mut self, key: U256) -> Self {
        self.storage_reads.push(key);
        self
    }

    /// Add a storage change (multiple writes to a slot grouped in `SlotChanges`).
    pub fn with_storage_change(mut self, change: SlotChanges) -> Self {
        self.storage_changes.push(change);
        self
    }

    /// Add a balance change.
    pub fn with_balance_change(mut self, change: BalanceChange) -> Self {
        self.balance_changes.push(change);
        self
    }

    /// Add a nonce change.
    pub fn with_nonce_change(mut self, change: NonceChange) -> Self {
        self.nonce_changes.push(change);
        self
    }

    /// Add a code change.
    pub fn with_code_change(mut self, change: CodeChange) -> Self {
        self.code_changes.push(change);
        self
    }

    /// Add multiple storage reads at once.
    pub fn extend_storage_reads<I>(mut self, iter: I) -> Self
    where
        I: IntoIterator<Item = U256>,
    {
        self.storage_reads.extend(iter);
        self
    }

    /// Add multiple slot changes at once.
    pub fn extend_storage_changes<I>(mut self, iter: I) -> Self
    where
        I: IntoIterator<Item = SlotChanges>,
    {
        self.storage_changes.extend(iter);
        self
    }
}

/// Hashes the given code, avoiding the hash of the empty code.
fn code_hash(code: &[u8]) -> B256 {
    if code.is_empty() { KECCAK256_EMPTY } else { keccak256(code) }
}

/// Keeps only the last entry of the list, applying `stamp` to it.
fn keep_last<T>(changes: &mut Vec<T>, stamp: impl FnOnce(&mut T)) {
    if let Some(mut change) = changes.pop() {
        stamp(&mut change);
        changes.clear();
        changes.push(change);
    }
}

fn merge_slot_changes(existing: &mut Vec<SlotChanges>, incoming: Vec<SlotChanges>) {
    let mut slot_positions = existing
        .iter()
        .enumerate()
        .map(|(idx, slot_changes)| (slot_changes.slot, idx))
        .collect::<HashMap<_, _>>();

    for slot_changes in incoming {
        if let Some(&idx) = slot_positions.get(&slot_changes.slot) {
            existing[idx].changes.extend(slot_changes.changes);
        } else {
            slot_positions.insert(slot_changes.slot, existing.len());
            existing.push(slot_changes);
        }
    }
}

#[cfg(test)]
mod merge_tests {
    use crate::{BlockAccessIndex, StorageChange};

    use super::*;
    use alloy_primitives::Bytes;

    #[test]
    fn merge_groups_slot_changes_and_appends_account_changes() {
        let address = Address::from([0x11; 20]);
        let mut existing = AccountChanges {
            address,
            storage_changes: vec![SlotChanges::new(
                U256::from(1),
                vec![StorageChange::new(BlockAccessIndex::new(0), U256::from(10))],
            )],
            storage_reads: vec![U256::from(3)],
            balance_changes: vec![BalanceChange::new(BlockAccessIndex::new(1), U256::from(100))],
            nonce_changes: vec![NonceChange::new(BlockAccessIndex::new(2), 7)],
            code_changes: vec![],
        };
        let incoming = AccountChanges {
            address,
            storage_changes: vec![
                SlotChanges::new(
                    U256::from(1),
                    vec![StorageChange::new(BlockAccessIndex::new(3), U256::from(20))],
                ),
                SlotChanges::new(
                    U256::from(2),
                    vec![StorageChange::new(BlockAccessIndex::new(4), U256::from(30))],
                ),
            ],
            storage_reads: vec![U256::from(4)],
            balance_changes: vec![BalanceChange::new(BlockAccessIndex::new(5), U256::from(150))],
            nonce_changes: vec![NonceChange::new(BlockAccessIndex::new(6), 8)],
            code_changes: vec![CodeChange::new(
                BlockAccessIndex::new(7),
                Bytes::from_static(&[0xaa]),
            )],
        };

        existing.merge(incoming);

        assert_eq!(existing.storage_reads, vec![U256::from(3), U256::from(4)]);
        assert_eq!(
            existing.storage_changes.iter().map(|changes| changes.slot).collect::<Vec<_>>(),
            vec![U256::from(1), U256::from(2)]
        );
        assert_eq!(
            existing.storage_changes[0]
                .changes
                .iter()
                .map(|change| change.new_value)
                .collect::<Vec<_>>(),
            vec![U256::from(10), U256::from(20)]
        );
        assert_eq!(existing.balance_changes.len(), 2);
        assert_eq!(existing.nonce_changes.len(), 2);
        assert_eq!(existing.code_changes.len(), 1);
    }

    #[test]
    fn merge_normalizes_storage_reads_after_cross_block_merge() {
        let address = Address::from([0x33; 20]);
        const A: U256 = U256::from_limbs([1, 0, 0, 0]);
        const B: U256 = U256::from_limbs([2, 0, 0, 0]);
        const C: U256 = U256::from_limbs([3, 0, 0, 0]);
        const D: U256 = U256::from_limbs([4, 0, 0, 0]);

        let mut existing = AccountChanges {
            address,
            storage_changes: vec![SlotChanges::new(
                A,
                vec![StorageChange::new(BlockAccessIndex::new(0), U256::from(10))],
            )],
            storage_reads: vec![B, C],
            balance_changes: vec![],
            nonce_changes: vec![],
            code_changes: vec![],
        };
        let incoming = AccountChanges {
            address,
            storage_changes: vec![SlotChanges::new(
                B,
                vec![StorageChange::new(BlockAccessIndex::new(1), U256::from(20))],
            )],
            storage_reads: vec![A, C, D],
            balance_changes: vec![],
            nonce_changes: vec![],
            code_changes: vec![],
        };

        existing.merge(incoming);

        assert_eq!(
            existing
                .storage_changes
                .iter()
                .map(|slot_changes| slot_changes.slot)
                .collect::<Vec<_>>(),
            vec![A, B]
        );
        assert_eq!(existing.storage_reads, vec![C, D]);
        assert!(existing.storage_reads.iter().all(|read_slot| {
            !existing.storage_changes.iter().any(|slot_changes| slot_changes.slot == *read_slot)
        }));
    }

    #[test]
    #[should_panic(expected = "cannot merge account changes for different addresses")]
    fn merge_rejects_different_addresses() {
        let mut existing = AccountChanges::new(Address::from([0x11; 20]));
        let incoming = AccountChanges::new(Address::from([0x22; 20]));

        existing.merge(incoming);
    }
}

#[cfg(test)]
mod sort_tests {
    use crate::{BlockAccessIndex, StorageChange};

    use super::*;
    use alloy_primitives::Bytes;

    #[test]
    fn sort_orders_account_local_eip7928_lists() {
        let mut account = AccountChanges {
            address: Address::from([0x11; 20]),
            storage_changes: vec![
                SlotChanges::new(
                    U256::from(3),
                    vec![
                        StorageChange::new(BlockAccessIndex::new(8), U256::from(0x80)),
                        StorageChange::new(BlockAccessIndex::new(2), U256::from(0x20)),
                    ],
                ),
                SlotChanges::new(
                    U256::from(1),
                    vec![
                        StorageChange::new(BlockAccessIndex::new(5), U256::from(0x50)),
                        StorageChange::new(BlockAccessIndex::new(1), U256::from(0x10)),
                    ],
                ),
            ],
            storage_reads: vec![U256::from(4), U256::from(2)],
            balance_changes: vec![
                BalanceChange::new(BlockAccessIndex::new(6), U256::from(600)),
                BalanceChange::new(BlockAccessIndex::new(3), U256::from(300)),
            ],
            nonce_changes: vec![
                NonceChange::new(BlockAccessIndex::new(7), 70),
                NonceChange::new(BlockAccessIndex::new(4), 40),
            ],
            code_changes: vec![
                CodeChange::new(BlockAccessIndex::new(9), Bytes::from_static(&[0x60, 0x09])),
                CodeChange::new(BlockAccessIndex::new(5), Bytes::from_static(&[0x60, 0x05])),
            ],
        };

        account.sort();

        assert_eq!(
            account.storage_changes.iter().map(|changes| changes.slot).collect::<Vec<_>>(),
            vec![U256::from(1), U256::from(3)]
        );
        assert_eq!(
            account.storage_changes[0]
                .changes
                .iter()
                .map(|change| change.block_access_index)
                .collect::<Vec<_>>(),
            vec![BlockAccessIndex::new(1), BlockAccessIndex::new(5)]
        );
        assert_eq!(
            account.storage_changes[1]
                .changes
                .iter()
                .map(|change| change.block_access_index)
                .collect::<Vec<_>>(),
            vec![BlockAccessIndex::new(2), BlockAccessIndex::new(8)]
        );
        assert_eq!(account.storage_reads, vec![U256::from(2), U256::from(4)]);
        assert_eq!(
            account
                .balance_changes
                .iter()
                .map(|change| change.block_access_index)
                .collect::<Vec<_>>(),
            vec![BlockAccessIndex::new(3), BlockAccessIndex::new(6)]
        );
        assert_eq!(
            account
                .nonce_changes
                .iter()
                .map(|change| change.block_access_index)
                .collect::<Vec<_>>(),
            vec![BlockAccessIndex::new(4), BlockAccessIndex::new(7)]
        );
        assert_eq!(
            account.code_changes.iter().map(|change| change.block_access_index).collect::<Vec<_>>(),
            vec![BlockAccessIndex::new(5), BlockAccessIndex::new(9)]
        );
    }
}

#[cfg(test)]
mod post_state_tests {
    use crate::{BlockAccessIndex, StorageChange};

    use super::*;

    #[test]
    fn account_post_states_are_absent_for_unchanged_fields() {
        let account = AccountChanges::new(Address::ZERO)
            .with_storage_read(U256::from(1))
            .with_storage_change(SlotChanges::new(
                U256::from(2),
                vec![StorageChange::new(BlockAccessIndex::new(1), U256::from(3))],
            ));

        assert_eq!(account.balance_post_state(), None);
        assert_eq!(account.nonce_post_state(), None);
        assert_eq!(account.code_post_state(), None);
    }

    #[test]
    fn account_post_states_use_last_recorded_change() {
        for indices in [&[0][..], &[0, 1, 2][..], &[2, 1, 0][..]] {
            let mut account = AccountChanges::new(Address::ZERO);
            for (position, &index) in indices.iter().enumerate() {
                let index = BlockAccessIndex::new(index);
                let value = (position + 1) as u64;
                account.balance_changes.push(BalanceChange::new(index, U256::from(value)));
                account.nonce_changes.push(NonceChange::new(index, value));
                account.code_changes.push(CodeChange::new(index, Bytes::from(vec![value as u8])));
            }

            let expected = indices.len() as u64;
            assert_eq!(account.balance_post_state(), Some(U256::from(expected)));
            assert_eq!(account.nonce_post_state(), Some(expected));
            assert_eq!(account.code_post_state(), Some(&Bytes::from(vec![expected as u8])));
        }
    }

    #[test]
    fn account_post_states_preserve_zero_values_and_cleared_code() {
        let mut account = AccountChanges::new(Address::ZERO)
            .with_balance_change(BalanceChange::new(BlockAccessIndex::new(0), U256::from(10)))
            .with_nonce_change(NonceChange::new(BlockAccessIndex::new(0), 1))
            .with_code_change(CodeChange::new(
                BlockAccessIndex::new(0),
                Bytes::from_static(&[0x60]),
            ));
        let index = BlockAccessIndex::new(1);
        account.balance_changes.push(BalanceChange::new(index, U256::ZERO));
        account.nonce_changes.push(NonceChange::new(index, 0));
        account.code_changes.push(CodeChange::new(index, Bytes::new()));

        assert_eq!(account.balance_post_state(), Some(U256::ZERO));
        assert_eq!(account.nonce_post_state(), Some(0));
        assert_eq!(account.code_post_state(), Some(&Bytes::new()));
    }

    #[test]
    fn storage_post_states_yields_last_change_per_slot() {
        let account = AccountChanges::new(Address::from([0x11; 20]))
            .with_storage_change(SlotChanges::new(
                U256::from(1),
                vec![
                    StorageChange::new(BlockAccessIndex::new(0), U256::from(0xaa)),
                    StorageChange::new(BlockAccessIndex::new(2), U256::from(0xbb)),
                ],
            ))
            .with_storage_change(SlotChanges::new(
                U256::from(3),
                vec![
                    StorageChange::new(BlockAccessIndex::new(1), U256::from(0xcc)),
                    StorageChange::new(BlockAccessIndex::new(3), U256::from(0xdd)),
                ],
            ));

        let post_states = account.storage_post_states().collect::<Vec<_>>();

        assert_eq!(
            post_states,
            vec![(U256::from(1), U256::from(0xbb)), (U256::from(3), U256::from(0xdd))]
        );
    }

    #[test]
    fn code_post_state_hash_matches_the_last_recorded_code() {
        let code = Bytes::from_static(&[0x60, 0x00, 0x56]);
        let account = AccountChanges::new(Address::ZERO)
            .with_code_change(CodeChange::new(
                BlockAccessIndex::new(0),
                Bytes::from_static(&[0x00]),
            ))
            .with_code_change(CodeChange::new(BlockAccessIndex::new(1), code.clone()));

        assert_eq!(account.code_hash_post_state(), Some(keccak256(&code)));
        assert_eq!(account.code_post_state_with_hash(), Some((keccak256(&code), &code)));
    }

    #[test]
    fn cleared_code_post_state_hashes_to_the_empty_code_hash() {
        let account = AccountChanges::new(Address::ZERO)
            .with_code_change(CodeChange::new(BlockAccessIndex::new(0), Bytes::new()));

        assert_eq!(account.code_hash_post_state(), Some(KECCAK256_EMPTY));
        assert_eq!(account.code_post_state_with_hash(), Some((KECCAK256_EMPTY, &Bytes::new())));
    }

    #[test]
    fn unchanged_code_has_no_post_state_hash() {
        let account = AccountChanges::new(Address::ZERO).with_storage_read(U256::from(1));

        assert_eq!(account.code_hash_post_state(), None);
        assert_eq!(account.code_post_state_with_hash(), None);
    }
}

#[cfg(test)]
mod has_changes_tests {
    use super::*;
    use crate::{BlockAccessIndex, StorageChange};

    #[test]
    fn read_only_entries_have_no_changes() {
        let account = AccountChanges::new(Address::ZERO).with_storage_read(U256::from(1));

        assert!(!account.has_changes());
        assert!(!account.is_empty());
        assert!(account.account_info().is_empty());
    }

    #[test]
    fn empty_slot_entries_have_no_changes() {
        let account = AccountChanges::new(Address::ZERO)
            .with_storage_change(SlotChanges::new(U256::from(1), Vec::new()));

        assert!(!account.has_changes());
    }

    #[test]
    fn every_change_kind_counts_as_a_change() {
        let index = BlockAccessIndex::new(0);
        let entries = [
            AccountChanges::new(Address::ZERO).with_storage_change(SlotChanges::new(
                U256::from(1),
                vec![StorageChange::new(index, U256::from(2))],
            )),
            AccountChanges::new(Address::ZERO)
                .with_balance_change(BalanceChange::new(index, U256::from(1))),
            AccountChanges::new(Address::ZERO).with_nonce_change(NonceChange::new(index, 1)),
            AccountChanges::new(Address::ZERO)
                .with_code_change(CodeChange::new(index, Bytes::new())),
        ];

        for account in entries {
            assert!(account.has_changes());
        }
    }

    #[test]
    fn account_info_matches_the_post_state_accessors() {
        let account = AccountChanges::new(Address::ZERO)
            .with_balance_change(BalanceChange::new(BlockAccessIndex::new(0), U256::from(7)));

        assert_eq!(account.account_info(), BalAccountInfo::from_changes(&account));
        assert_eq!(account.account_info().balance, account.balance_post_state());
    }
}

#[cfg(test)]
mod storage_slots_tests {
    use crate::{BlockAccessIndex, StorageChange};

    use super::*;

    #[test]
    fn storage_slots_yields_changed_then_read_slots() {
        let account = AccountChanges::new(Address::ZERO)
            .with_storage_change(SlotChanges::new(
                U256::from(1),
                vec![StorageChange::new(BlockAccessIndex::new(0), U256::ZERO)],
            ))
            .with_storage_change(SlotChanges::new(
                U256::from(2),
                vec![StorageChange::new(BlockAccessIndex::new(1), U256::ZERO)],
            ))
            .extend_storage_reads([U256::from(3), U256::from(4)]);

        assert_eq!(
            account.storage_slots().collect::<Vec<_>>(),
            vec![U256::from(1), U256::from(2), U256::from(3), U256::from(4)]
        );
    }
}

#[cfg(all(test, feature = "serde"))]
mod tests {
    use crate::{BlockAccessIndex, BlockAccessList, StorageChange};

    use super::*;
    use alloy_primitives::Bytes;
    use serde_json;

    #[test]
    fn test_account_changes_serde() {
        let acc = AccountChanges {
            address: Address::from([0x11; 20]),
            storage_changes: vec![SlotChanges {
                slot: U256::from(1),
                changes: vec![StorageChange {
                    block_access_index: BlockAccessIndex::new(0),
                    new_value: U256::from(100),
                }],
            }],
            storage_reads: vec![U256::from(2)],
            balance_changes: vec![BalanceChange {
                block_access_index: BlockAccessIndex::new(1),
                post_balance: U256::from(1000),
            }],
            nonce_changes: vec![NonceChange {
                block_access_index: BlockAccessIndex::new(2),
                new_nonce: 42,
            }],
            code_changes: vec![CodeChange {
                block_access_index: BlockAccessIndex::new(3),
                new_code: Bytes::from(vec![0x60, 0x00]),
            }],
        };

        let json = serde_json::to_string(&acc).unwrap();
        let value: serde_json::Value = serde_json::from_str(&json).unwrap();
        assert_eq!(value["storageChanges"][0]["key"], "0x1");
        assert_eq!(value["storageChanges"][0]["changes"][0]["value"], "0x64");
        assert_eq!(value["storageReads"][0], "0x2");
        assert_eq!(value["balanceChanges"][0]["value"], "0x3e8");
        assert_eq!(value["nonceChanges"][0]["value"], "0x2a");
        assert_eq!(value["codeChanges"][0]["code"], "0x6000");
        let decoded: AccountChanges = serde_json::from_str(&json).unwrap();

        assert_eq!(acc, decoded);
    }

    #[test]
    fn test_storage_reads_deserialize_compact_quantities() {
        let fixture = r#"
        {
            "address": "0x1111111111111111111111111111111111111111",
            "storageChanges": [],
            "storageReads": [
                "0x00",
                "0x01",
                "0x02"
            ],
            "balanceChanges": [],
            "nonceChanges": [],
            "codeChanges": []
        }
        "#;

        let decoded: AccountChanges = serde_json::from_str(fixture).unwrap();
        assert_eq!(decoded.storage_reads, vec![U256::ZERO, U256::from(1), U256::from(2)]);

        assert_eq!(
            serde_json::to_value(decoded).unwrap()["storageReads"],
            serde_json::json!(["0x0", "0x1", "0x2"])
        );
    }

    #[test]
    fn test_eest_storage_fields_deserialize_compact_quantities() {
        // Extracted from tests-glamsterdam-devnet@v7.2.0's precompile_warming.json fixture.
        let fixture = r#"
        [
          {
            "address": "0x0000f90827f1c53a10cb7a02335b175320002935",
            "storageChanges": [
              {
                "slot": "0x01",
                "slotChanges": [
                  {
                    "blockAccessIndex": "0x00",
                    "postValue": "0x27330b1c525088b9b5ed2ced86b42d53378c8f6b384e8c3897493e851bc026df"
                  }
                ]
              }
            ],
            "storageReads": [],
            "balanceChanges": [],
            "nonceChanges": [],
            "codeChanges": []
          },
          {
            "address": "0x000f3df6d732807ef1319fb7b8bb8522d0beac02",
            "storageChanges": [
              {
                "slot": "0x0e22",
                "slotChanges": [
                  {
                    "blockAccessIndex": "0x00",
                    "postValue": "0x4e20"
                  }
                ]
              }
            ],
            "storageReads": ["0x2e21"],
            "balanceChanges": [],
            "nonceChanges": [],
            "codeChanges": []
          }
        ]
        "#;

        let decoded: BlockAccessList = serde_json::from_str(fixture).unwrap();
        assert_eq!(decoded[0].storage_changes[0].slot, U256::from(1));
        assert_eq!(decoded[1].storage_changes[0].slot, U256::from(0x0e22));
        assert_eq!(decoded[1].storage_changes[0].changes[0].new_value, U256::from(0x4e20));
        assert_eq!(decoded[1].storage_reads, vec![U256::from(0x2e21)]);
    }

    #[test]
    fn test_vec_account_changes_serde() {
        let acc1 = AccountChanges::new(Address::from([0x11; 20]))
            .with_storage_read(U256::from(1))
            .with_balance_change(BalanceChange {
                block_access_index: BlockAccessIndex::new(0),
                post_balance: U256::from(100),
            });

        let acc2 = AccountChanges::new(Address::from([0x22; 20]))
            .with_storage_change(SlotChanges {
                slot: U256::from(2),
                changes: vec![StorageChange {
                    block_access_index: BlockAccessIndex::new(1),
                    new_value: U256::from(200),
                }],
            })
            .with_nonce_change(NonceChange {
                block_access_index: BlockAccessIndex::new(2),
                new_nonce: 42,
            });

        let acc3 = AccountChanges::new(Address::from([0x33; 20])).with_code_change(CodeChange {
            block_access_index: BlockAccessIndex::new(3),
            new_code: Bytes::from(vec![0x60, 0x00]),
        });

        let vec_acc = vec![acc1, acc2, acc3];

        let json = serde_json::to_string(&vec_acc).unwrap();
        let decoded: Vec<AccountChanges> = serde_json::from_str(&json).unwrap();

        assert_eq!(vec_acc, decoded);
    }

    #[test]
    fn test_block_access_list_serde_roundtrip_from_populated_fixture() {
        let fixture = r#"
[
  {
    "address": "0x1111111111111111111111111111111111111111",
    "storageChanges": [
      {
        "key": "0x1",
        "changes": [
          {
            "index": "0x1",
            "value": "0x10"
          },
          {
            "index": "0x2",
            "value": "0x20"
          }
        ]
      }
    ],
    "storageReads": [
      "0x2"
    ],
    "balanceChanges": [
      {
        "index": "0x3",
        "value": "0x3e8"
      }
    ],
    "nonceChanges": [
      {
        "index": "0x4",
        "value": "0x2a"
      }
    ],
    "codeChanges": [
      {
        "index": "0x5",
        "code": "0x6000"
      }
    ]
  }
]
"#;

        let decoded: BlockAccessList = serde_json::from_str(fixture).unwrap();
        let serialized = serde_json::to_string(&decoded).unwrap();
        let fixture_value: serde_json::Value = serde_json::from_str(fixture).unwrap();
        let serialized_value: serde_json::Value = serde_json::from_str(&serialized).unwrap();

        assert!(fixture_value.is_array());
        assert_eq!(fixture_value, serialized_value);
    }

    #[test]
    fn test_block_access_list_serde_roundtrip_from_empty_fixture() {
        let fixture = r#"
[
  {
    "address": "0x2222222222222222222222222222222222222222",
    "storageChanges": [],
    "storageReads": [],
    "balanceChanges": [],
    "nonceChanges": [],
    "codeChanges": []
  }
]
"#;

        let decoded: BlockAccessList = serde_json::from_str(fixture).unwrap();
        let serialized = serde_json::to_string(&decoded).unwrap();
        let fixture_value: serde_json::Value = serde_json::from_str(fixture).unwrap();
        let serialized_value: serde_json::Value = serde_json::from_str(&serialized).unwrap();

        assert!(fixture_value.is_array());
        assert_eq!(fixture_value, serialized_value);
        assert_eq!(serialized_value[0]["storageChanges"], serde_json::json!([]));
        assert_eq!(serialized_value[0]["storageReads"], serde_json::json!([]));
        assert_eq!(serialized_value[0]["balanceChanges"], serde_json::json!([]));
        assert_eq!(serialized_value[0]["nonceChanges"], serde_json::json!([]));
        assert_eq!(serialized_value[0]["codeChanges"], serde_json::json!([]));
    }
}