feat(anvil): configure slots_in_an_epoch (#7335)

* feat(anvil): configure slots_in_an_epoch

* Option nit

Co-authored-by: DaniPopes <57450786+DaniPopes@users.noreply.github.com>

* nit: use primitive u64

* nit: semicolon

* nits

Co-authored-by: Matthias Seitz <matthias.seitz@outlook.de>

* nit: anvil config

---------

Co-authored-by: DaniPopes <57450786+DaniPopes@users.noreply.github.com>
Co-authored-by: Matthias Seitz <matthias.seitz@outlook.de>

crates/anvil/src/cmd.rs

@@ -86,6 +86,10 @@ pub struct NodeArgs {
     #[arg(short, long, visible_alias = "blockTime", value_name = "SECONDS")]
     pub block_time: Option<u64>,
 
+    /// Slots in an epoch
+    #[arg(long, value_name = "SLOTS_IN_AN_EPOCH", default_value_t = 32)]
+    pub slots_in_an_epoch: u64,
+
     /// Writes output of `anvil` as json to user-specified file.
     #[arg(long, value_name = "OUT_FILE")]
     pub config_out: Option<String>,
@@ -230,6 +234,7 @@ impl NodeArgs {
             .with_transaction_block_keeper(self.transaction_block_keeper)
             .with_optimism(self.evm_opts.optimism)
             .with_disable_default_create2_deployer(self.evm_opts.disable_default_create2_deployer)
+            .with_slots_in_an_epoch(self.slots_in_an_epoch)
     }
 
     fn account_generator(&self) -> AccountGenerator {

crates/anvil/src/config.rs

@@ -170,6 +170,8 @@ pub struct NodeConfig {
     pub disable_default_create2_deployer: bool,
     /// Enable Optimism deposit transaction
     pub enable_optimism: bool,
+    /// Slots in an epoch
+    pub slots_in_an_epoch: u64,
 }
 
 impl NodeConfig {
@@ -404,6 +406,7 @@ impl Default for NodeConfig {
             transaction_block_keeper: None,
             disable_default_create2_deployer: false,
             enable_optimism: false,
+            slots_in_an_epoch: 32,
         }
     }
 }
@@ -596,6 +599,13 @@ impl NodeConfig {
         self
     }
 
+    /// Sets the slots in an epoch
+    #[must_use]
+    pub fn with_slots_in_an_epoch(mut self, slots_in_an_epoch: u64) -> Self {
+        self.slots_in_an_epoch = slots_in_an_epoch;
+        self
+    }
+
     /// Sets the port to use
     #[must_use]
     pub fn with_port(mut self, port: u16) -> Self {

crates/anvil/src/eth/backend/mem/mod.rs

@@ -168,6 +168,8 @@ pub struct Backend {
     /// max number of blocks with transactions in memory
     transaction_block_keeper: Option<usize>,
     node_config: Arc<AsyncRwLock<NodeConfig>>,
+    /// Slots in an epoch
+    slots_in_an_epoch: u64,
 }
 
 impl Backend {
@@ -214,6 +216,8 @@ impl Backend {
             Default::default()
         };
 
+        let slots_in_an_epoch = node_config.read().await.slots_in_an_epoch;
+
         let backend = Self {
             db,
             blockchain,
@@ -230,6 +234,7 @@ impl Backend {
             prune_state_history_config,
             transaction_block_keeper,
             node_config,
+            slots_in_an_epoch,
         };
 
         if let Some(interval_block_time) = automine_block_time {
@@ -1478,7 +1483,7 @@ impl Backend {
             BlockId::Hash(hash) => hash.block_hash,
             BlockId::Number(number) => {
                 let storage = self.blockchain.storage.read();
-                let slots_in_an_epoch = U64::from(32u64);
+                let slots_in_an_epoch = U64::from(self.slots_in_an_epoch);
                 match number {
                     BlockNumber::Latest => storage.best_hash,
                     BlockNumber::Earliest => storage.genesis_hash,
@@ -1599,7 +1604,6 @@ impl Backend {
         block_id: Option<T>,
     ) -> Result<u64, BlockchainError> {
         let current = self.best_number();
-        let slots_in_an_epoch = 32u64;
         let requested =
             match block_id.map(Into::into).unwrap_or(BlockId::Number(BlockNumber::Latest)) {
                 BlockId::Hash(hash) => self
@@ -1614,12 +1618,8 @@ impl Backend {
                     BlockNumber::Latest | BlockNumber::Pending => self.best_number(),
                     BlockNumber::Earliest => U64::ZERO.to::<u64>(),
                     BlockNumber::Number(num) => num,
-                    BlockNumber::Safe => {
-                        U64::from(current).saturating_sub(U64::from(slots_in_an_epoch)).to::<u64>()
-                    }
-                    BlockNumber::Finalized => U64::from(current)
-                        .saturating_sub(U64::from(slots_in_an_epoch) * U64::from(2))
-                        .to::<u64>(),
+                    BlockNumber::Safe => current.saturating_sub(self.slots_in_an_epoch),
+                    BlockNumber::Finalized => current.saturating_sub(self.slots_in_an_epoch * 2),
                 },
             };
 
@@ -1632,13 +1632,12 @@ impl Backend {
 
     pub fn convert_block_number(&self, block: Option<BlockNumber>) -> u64 {
         let current = self.best_number();
-        let slots_in_an_epoch = 32u64;
         match block.unwrap_or(BlockNumber::Latest) {
             BlockNumber::Latest | BlockNumber::Pending => current,
             BlockNumber::Earliest => 0,
             BlockNumber::Number(num) => num,
-            BlockNumber::Safe => current.saturating_sub(slots_in_an_epoch),
-            BlockNumber::Finalized => current.saturating_sub(slots_in_an_epoch * 2),
+            BlockNumber::Safe => current.saturating_sub(self.slots_in_an_epoch),
+            BlockNumber::Finalized => current.saturating_sub(self.slots_in_an_epoch * 2),
         }
     }