feat: procure l2 gas price when forking (#290)

* feat: procure `l2_fair_gas_price` from fork source

* chore: explicit info when overriding l2 gas price

src/fork.rs

@@ -309,7 +309,7 @@ pub trait ForkSource {
 /// "S" is the implementation of the ForkSource.
 #[derive(Debug, Clone)]
 pub struct ForkDetails<S> {
-    // Source of the fork data (for example HTTPForkSoruce)
+    // Source of the fork data (for example HTTPForkSource)
     pub fork_source: S,
     // Block number at which we forked (the next block to create is l1_block + 1)
     pub l1_block: L1BatchNumber,
@@ -320,6 +320,7 @@ pub struct ForkDetails<S> {
     pub block_timestamp: u64,
     pub overwrite_chain_id: Option<L2ChainId>,
     pub l1_gas_price: u64,
+    pub l2_fair_gas_price: u64,
 }
 
 const SUPPORTED_VERSIONS: &[ProtocolVersionId] = &[
@@ -385,8 +386,8 @@ impl ForkDetails<HttpForkSource> {
         let l1_batch_number = block_details.l1_batch_number;
 
         tracing::info!(
-            "Creating fork from {:?} L1 block: {:?} L2 block: {:?} with timestamp {:?}, L1 gas price {:?} and protocol version: {:?}" ,
-            url, l1_batch_number, miniblock, block_details.base.timestamp, block_details.base.l1_gas_price, block_details.protocol_version
+            "Creating fork from {:?} L1 block: {:?} L2 block: {:?} with timestamp {:?}, L1 gas price {:?}, L2 fair gas price {:?} and protocol version: {:?}" ,
+            url, l1_batch_number, miniblock, block_details.base.timestamp, block_details.base.l1_gas_price, block_details.base.l2_fair_gas_price, block_details.protocol_version
         );
 
         if !block_details
@@ -410,6 +411,7 @@ impl ForkDetails<HttpForkSource> {
             l2_miniblock_hash: root_hash,
             overwrite_chain_id: chain_id,
             l1_gas_price: block_details.base.l1_gas_price,
+            l2_fair_gas_price: block_details.base.l2_fair_gas_price,
         }
     }
     /// Create a fork from a given network at a given height.
@@ -506,7 +508,7 @@ mod tests {
     use zksync_state::ReadStorage;
     use zksync_types::{api::TransactionVariant, StorageKey};
 
-    use crate::{deps::InMemoryStorage, system_contracts, testing};
+    use crate::{deps::InMemoryStorage, node::DEFAULT_L2_GAS_PRICE, system_contracts, testing};
 
     use super::{ForkDetails, ForkStorage};
 
@@ -535,6 +537,7 @@ mod tests {
             block_timestamp: 0,
             overwrite_chain_id: None,
             l1_gas_price: 100,
+            l2_fair_gas_price: DEFAULT_L2_GAS_PRICE,
         };
 
         let mut fork_storage = ForkStorage::new(Some(fork_details), &options);

src/main.rs

@@ -1,6 +1,7 @@
 use crate::cache::CacheConfig;
 use crate::node::{InMemoryNodeConfig, ShowGasDetails, ShowStorageLogs, ShowVMDetails};
 use crate::observability::Observability;
+use crate::utils::to_human_size;
 use clap::{Parser, Subcommand, ValueEnum};
 use colored::Colorize;
 use fork::{ForkDetails, ForkSource};
@@ -232,9 +233,10 @@ struct Cli {
     /// Show Gas details information
     show_gas_details: ShowGasDetails,
 
-    #[arg(long, default_value_t = DEFAULT_L2_GAS_PRICE)]
-    /// If provided, uses a custom value as the L2 gas price.
-    l2_gas_price: u64,
+    #[arg(long)]
+    /// If provided, uses a custom value as the L2 gas price. If not provided the gas price will be
+    /// inferred from the protocol version.
+    l2_gas_price: Option<u64>,
 
     #[arg(long)]
     /// If true, the tool will try to contact openchain to resolve the ABI & topic names.
@@ -360,11 +362,38 @@ async fn main() -> anyhow::Result<()> {
         DevSystemContracts::Local => system_contracts::Options::Local,
     };
 
+    // If we're forking we set the price to be equal to that contained within
+    // `ForkDetails`. If not, we use the `DEFAULT_L2_GAS_PRICE` instead.
+    let mut l2_fair_gas_price = {
+        if let Some(f) = &fork_details {
+            f.l2_fair_gas_price
+        } else {
+            DEFAULT_L2_GAS_PRICE
+        }
+    };
+
+    // If L2 gas price has been supplied as an argument, override the value
+    // procured previously.
+    match opt.l2_gas_price {
+        Some(l2_gas_price) => {
+            tracing::info!(
+                "Starting node with L2 gas price set to {} (overridden from {})",
+                to_human_size(l2_gas_price.into()),
+                to_human_size(l2_fair_gas_price.into())
+            );
+            l2_fair_gas_price = l2_gas_price;
+        }
+        None => tracing::info!(
+            "Starting node with L2 gas price set to {}",
+            to_human_size(l2_fair_gas_price.into())
+        ),
+    }
+
     let node = InMemoryNode::new(
         fork_details,
         Some(observability),
         InMemoryNodeConfig {
-            l2_gas_price: opt.l2_gas_price,
+            l2_fair_gas_price,
             show_calls: opt.show_calls,
             show_outputs: opt.show_outputs,
             show_storage_logs: opt.show_storage_logs,

src/node/in_memory.rs

@@ -880,7 +880,7 @@ pub struct Snapshot {
 #[derive(Debug, Clone)]
 pub struct InMemoryNodeConfig {
     // The values to be used when calculating gas.
-    pub l2_gas_price: u64,
+    pub l2_fair_gas_price: u64,
     pub show_calls: ShowCalls,
     pub show_outputs: bool,
     pub show_storage_logs: ShowStorageLogs,
@@ -893,7 +893,7 @@ pub struct InMemoryNodeConfig {
 impl Default for InMemoryNodeConfig {
     fn default() -> Self {
         Self {
-            l2_gas_price: DEFAULT_L2_GAS_PRICE,
+            l2_fair_gas_price: DEFAULT_L2_GAS_PRICE,
             show_calls: Default::default(),
             show_outputs: Default::default(),
             show_storage_logs: Default::default(),
@@ -952,7 +952,7 @@ impl<S: ForkSource + std::fmt::Debug + Clone> InMemoryNode<S> {
                 current_miniblock_hash: f.l2_miniblock_hash,
                 fee_input_provider: TestNodeFeeInputProvider::new(
                     f.l1_gas_price,
-                    config.l2_gas_price,
+                    config.l2_fair_gas_price,
                 ),
                 tx_results: Default::default(),
                 blocks,
@@ -989,7 +989,7 @@ impl<S: ForkSource + std::fmt::Debug + Clone> InMemoryNode<S> {
                 current_miniblock_hash: block_hash,
                 fee_input_provider: TestNodeFeeInputProvider::new(
                     L1_GAS_PRICE,
-                    config.l2_gas_price,
+                    config.l2_fair_gas_price,
                 ),
                 tx_results: Default::default(),
                 blocks,
@@ -1887,6 +1887,7 @@ mod tests {
                 block_timestamp: 1002,
                 overwrite_chain_id: None,
                 l1_gas_price: 1000,
+                l2_fair_gas_price: DEFAULT_L2_GAS_PRICE,
             }),
             None,
             Default::default(),