foundry_evm_core/
state_snapshot.rs

1//! Support for snapshotting different states
2
3use alloy_primitives::{U256, map::HashMap};
4
5/// Represents all state snapshots
6#[derive(Clone, Debug)]
7pub struct StateSnapshots<T> {
8    id: U256,
9    state_snapshots: HashMap<U256, T>,
10}
11
12impl<T> StateSnapshots<T> {
13    fn next_id(&mut self) -> U256 {
14        let id = self.id;
15        self.id = id.saturating_add(U256::from(1));
16        id
17    }
18
19    /// Returns the state snapshot with the given id `id`
20    pub fn get(&self, id: U256) -> Option<&T> {
21        self.state_snapshots.get(&id)
22    }
23
24    /// Returns `true` if there are no state snapshots.
25    pub fn is_empty(&self) -> bool {
26        self.state_snapshots.is_empty()
27    }
28
29    /// Removes the state snapshot with the given `id`.
30    ///
31    /// This will also remove any state snapshots taken after the state snapshot with the `id`.
32    /// e.g.: reverting to id 1 will delete snapshots with ids 1, 2, 3, etc.)
33    pub fn remove(&mut self, id: U256) -> Option<T> {
34        let snapshot_state = self.state_snapshots.remove(&id);
35
36        // Revert all state snapshots taken after the state snapshot with the `id`
37        let mut to_revert = id + U256::from(1);
38        while to_revert < self.id {
39            self.state_snapshots.remove(&to_revert);
40            to_revert += U256::from(1);
41        }
42
43        snapshot_state
44    }
45
46    /// Removes all state snapshots.
47    pub fn clear(&mut self) {
48        self.state_snapshots.clear();
49    }
50
51    /// Removes the state snapshot with the given `id`.
52    ///
53    /// Does not remove state snapshots after it.
54    pub fn remove_at(&mut self, id: U256) -> Option<T> {
55        self.state_snapshots.remove(&id)
56    }
57
58    /// Inserts the new state snapshot and returns the id.
59    pub fn insert(&mut self, state_snapshot: T) -> U256 {
60        let id = self.next_id();
61        self.state_snapshots.insert(id, state_snapshot);
62        id
63    }
64
65    /// Inserts the new state snapshot at the given `id`.
66    ///
67    ///  Does not auto-increment the next `id`.
68    pub fn insert_at(&mut self, state_snapshot: T, id: U256) {
69        self.state_snapshots.insert(id, state_snapshot);
70    }
71}
72
73impl<T> Default for StateSnapshots<T> {
74    fn default() -> Self {
75        Self { id: U256::ZERO, state_snapshots: HashMap::default() }
76    }
77}
foundry_evm_core/state_snapshot.rs

foundry_evm_core/
state_snapshot.rs
