feat(consensus): Isthmus Network Upgrade Txs (#405)

### Description

Drafts up the network upgrade transactions for the Isthmus hardfork.

- [EIP-2935](https://eips.ethereum.org/EIPS/eip-2935#deployment) ->
block hash contract
- ~~[EIP-7002](https://eips.ethereum.org/EIPS/eip-7002#deployment) ->
withdrawals request contract~~
- ~~[EIP-7251](https://eips.ethereum.org/EIPS/eip-7251#deployment) ->
consolidation requests contract~~

crates/consensus/src/hardforks/bytecode/eip2935_isthmus.hex

@@ -0,0 +1 @@
+60538060095f395ff33373fffffffffffffffffffffffffffffffffffffffe14604657602036036042575f35600143038111604257611fff81430311604257611fff9006545f5260205ff35b5f5ffd5b5f35611fff60014303065500

crates/consensus/src/hardforks/bytecode/isthmus_tx_1.hex

@@ -0,0 +1 @@
+7ef89ca0ebd6fc97ea8145b1e7b2e763e76bee378575ef495aa16eafbcf7325525bc1b47943462413af4609098e1e27a490f554f260213d6858080808303d09080b85c60538060095f395ff33373fffffffffffffffffffffffffffffffffffffffe14604657602036036042575f35600143038111604257611fff81430311604257611fff9006545f5260205ff35b5f5ffd5b5f35611fff60014303065500

crates/consensus/src/hardforks/forks.rs

@@ -1,6 +1,6 @@
 //! Contains all hardforks represented in the [crate::Hardfork] type.
 
-use crate::{Ecotone, Fjord};
+use crate::{Ecotone, Fjord, Isthmus};
 
 /// Optimism Hardforks
 ///
@@ -23,16 +23,26 @@ use crate::{Ecotone, Fjord};
 /// let fjord_upgrade_txs = Hardforks::FJORD.txs();
 /// assert_eq!(fjord_upgrade_txs.collect::<Vec<_>>().len(), 3);
 /// ```
+///
+/// Build isthmus hardfork upgrade transaction:
+/// ```rust
+/// use op_alloy_consensus::{Hardfork, Hardforks};
+/// let isthmus_upgrade_tx = Hardforks::ISTHMUS.txs();
+/// assert_eq!(isthmus_upgrade_tx.collect::<Vec<_>>().len(), 1);
+/// ```
 #[derive(Debug, Default, Clone, Copy)]
 #[non_exhaustive]
 pub struct Hardforks;
 
 impl Hardforks {
-    /// The ecotone hardfork upgrade transactions.
+    /// The Ecotone hardfork upgrade transactions.
     pub const ECOTONE: Ecotone = Ecotone;
 
-    /// The fjord hardfork upgrade transactions.
+    /// The Fjord hardfork upgrade transactions.
     pub const FJORD: Fjord = Fjord;
+
+    /// The Isthmus hardfork upgrade transactions.
+    pub const ISTHMUS: Isthmus = Isthmus;
 }
 
 #[cfg(test)]
@@ -48,5 +58,8 @@ mod tests {
 
         let fjord_upgrade_txs = Hardforks::FJORD.txs();
         assert_eq!(fjord_upgrade_txs.collect::<Vec<_>>().len(), 3);
+
+        let isthmus_upgrade_tx = Hardforks::ISTHMUS.txs();
+        assert_eq!(isthmus_upgrade_tx.collect::<Vec<_>>().len(), 1);
     }
 }

crates/consensus/src/hardforks/isthmus.rs

@@ -0,0 +1,86 @@
+//! Module containing a [Transaction] builder for the Isthmus network upgrade transactions.
+//!
+//! Isthmus network upgrade transactions are defined in the [OP Stack Specs][specs].
+//!
+//! [specs]: https://specs.optimism.io/protocol/isthmus/derivation.html#network-upgrade-automation-transactions
+//! [Transaction]: alloy_consensus::Transaction
+
+use crate::UpgradeDepositSource;
+use alloc::{string::String, vec::Vec};
+use alloy_eips::eip2718::Encodable2718;
+use alloy_primitives::{address, hex, Address, Bytes, TxKind, B256, U256};
+
+use crate::{Hardfork, TxDeposit};
+
+/// The Isthmus network upgrade transactions.
+#[derive(Debug, Default, Clone, Copy)]
+pub struct Isthmus;
+
+impl Isthmus {
+    /// EIP-2935 From Address
+    pub const EIP2935_FROM: Address = address!("3462413Af4609098e1E27A490f554f260213D685");
+
+    /// Returns the source hash for the Isthmus Deposit Contract deployment.
+    pub fn deposit_contract_source() -> B256 {
+        UpgradeDepositSource { intent: String::from("Isthmus: deposit contract deployment") }
+            .source_hash()
+    }
+
+    /// Returns the EIP-2935 creation data.
+    pub fn eip2935_creation_data() -> Bytes {
+        let contents = core::str::from_utf8(include_bytes!("./bytecode/eip2935_isthmus.hex"))
+            .expect("eip-2935 creation data is not valid UTF-8");
+        let contents = contents.replace("\n", "");
+        let decoded = hex::decode(contents).expect("eip-2935 creation data is not valid hex");
+        decoded.into()
+    }
+
+    /// Returns the list of [TxDeposit]s for the network upgrade.
+    pub fn deposits() -> impl Iterator<Item = TxDeposit> {
+        ([TxDeposit {
+            source_hash: Self::deposit_contract_source(),
+            from: Self::EIP2935_FROM,
+            to: TxKind::Create,
+            mint: 0.into(),
+            value: U256::ZERO,
+            gas_limit: 250_000,
+            is_system_transaction: false,
+            input: Self::eip2935_creation_data(),
+        }])
+        .into_iter()
+    }
+}
+
+impl Hardfork for Isthmus {
+    /// Constructs the network upgrade transactions.
+    fn txs(&self) -> impl Iterator<Item = Bytes> + '_ {
+        Self::deposits().map(|tx| {
+            let mut encoded = Vec::new();
+            tx.encode_2718(&mut encoded);
+            Bytes::from(encoded)
+        })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use alloc::vec;
+
+    #[test]
+    fn test_isthmus_txs_encoded() {
+        let isthmus_upgrade_tx = Isthmus.txs().collect::<Vec<_>>();
+        assert_eq!(isthmus_upgrade_tx.len(), 1);
+
+        let expected_first_tx = include_bytes!("./bytecode/isthmus_tx_1.hex");
+        let expected_first_tx =
+            core::str::from_utf8(expected_first_tx).expect("expected_first_tx is not valid UTF-8");
+        let expected_first_tx = expected_first_tx.replace("\n", "");
+        let expected_first_tx =
+            hex::decode(expected_first_tx).expect("expected_first_tx is not valid hex");
+        let expected_txs: Vec<Bytes> = vec![expected_first_tx.into()];
+        for (i, expected) in expected_txs.iter().enumerate() {
+            assert_eq!(isthmus_upgrade_tx[i], *expected);
+        }
+    }
+}

crates/consensus/src/hardforks/mod.rs

@@ -12,5 +12,8 @@ pub use fjord::Fjord;
 mod ecotone;
 pub use ecotone::Ecotone;
 
+mod isthmus;
+pub use isthmus::Isthmus;
+
 mod utils;
 pub(crate) use utils::upgrade_to_calldata;

crates/consensus/src/lib.rs

@@ -25,7 +25,7 @@ pub use eip1559::{
 };
 
 mod hardforks;
-pub use hardforks::{Ecotone, Fjord, Hardfork, Hardforks};
+pub use hardforks::{Ecotone, Fjord, Hardfork, Hardforks, Isthmus};
 
 mod source;
 pub use source::*;