feat: extract and export estimate_tx_compressed_size

crates/optimism/src/l1block.rs

@@ -1,4 +1,4 @@
-use crate::{fast_lz::flz_compress_len, OpSpecId};
+use crate::{transaction::estimate_tx_compressed_size, OpSpecId};
 use core::ops::Mul;
 use revm::{
     context_interface::Journal,
@@ -43,16 +43,6 @@ pub const BASE_FEE_RECIPIENT: Address = address!("420000000000000000000000000000
 /// The address of the L1Block contract.
 pub const L1_BLOCK_CONTRACT: Address = address!("4200000000000000000000000000000000000015");
 
-/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#L79>
-const L1_COST_FASTLZ_COEF: u64 = 836_500;
-
-/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#L78>
-/// Inverted to be used with `saturating_sub`.
-const L1_COST_INTERCEPT: u64 = 42_585_600;
-
-/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#82>
-const MIN_TX_SIZE_SCALED: u64 = 100 * 1_000_000;
-
 /// L1 block info
 ///
 /// We can extract L1 epoch data from each L2 block, by looking at the `setL1BlockValues`
@@ -171,14 +161,7 @@ impl L1BlockInfo {
     // This value is computed based on the following formula:
     // max(minTransactionSize, intercept + fastlzCoef*fastlzSize)
     fn tx_estimated_size_fjord(&self, input: &[u8]) -> U256 {
-        let fastlz_size = flz_compress_len(input) as u64;
-
-        U256::from(
-            fastlz_size
-                .saturating_mul(L1_COST_FASTLZ_COEF)
-                .saturating_sub(L1_COST_INTERCEPT)
-                .max(MIN_TX_SIZE_SCALED),
-        )
+        U256::from(estimate_tx_compressed_size(input))
     }
 
     /// Calculate the gas cost of a transaction based on L1 block data posted on L2, depending on the [OpSpec] passed.

crates/optimism/src/lib.rs

@@ -19,4 +19,4 @@ pub use l1block::{
 };
 pub use result::OptimismHaltReason;
 pub use spec::*;
-pub use transaction::{error::OpTransactionError, OpTransaction};
+pub use transaction::{error::OpTransactionError, estimate_tx_compressed_size, OpTransaction};

crates/optimism/src/transaction.rs

@@ -4,3 +4,25 @@ pub mod error;
 
 pub use abstraction::{OpTransaction, OpTxTrait};
 pub use error::OpTransactionError;
+
+use crate::fast_lz::flz_compress_len;
+
+/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#L79>
+const L1_COST_FASTLZ_COEF: u64 = 836_500;
+
+/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#L78>
+/// Inverted to be used with `saturating_sub`.
+const L1_COST_INTERCEPT: u64 = 42_585_600;
+
+/// <https://github.com/ethereum-optimism/op-geth/blob/647c346e2bef36219cc7b47d76b1cb87e7ca29e4/core/types/rollup_cost.go#82>
+const MIN_TX_SIZE_SCALED: u64 = 100 * 1_000_000;
+
+/// Estimates the compressed size of a transaction.
+pub fn estimate_tx_compressed_size(input: &[u8]) -> u64 {
+    let fastlz_size = flz_compress_len(input) as u64;
+
+    fastlz_size
+        .saturating_mul(L1_COST_FASTLZ_COEF)
+        .saturating_sub(L1_COST_INTERCEPT)
+        .max(MIN_TX_SIZE_SCALED)
+}