feat(l1, l2): add EIP-1898 blockHash support to eth_call (#6130)

## Summary
- Add support for the `blockHash` parameter to `eth_call` as specified
in [EIP-1898](https://eips.ethereum.org/EIPS/eip-1898)
- Previously, 5 of 6 EIP-1898 methods supported block hashes; only
`eth_call` used `BlockIdentifier` instead of `BlockIdentifierOrHash`
- Now all 6 methods are consistent: `eth_getBalance`,
`eth_getStorageAt`, `eth_getTransactionCount`, `eth_getCode`,
`eth_call`, and `eth_getProof`

## Changes
- Add `resolve_block_header()` method to `BlockIdentifierOrHash` in
`block_identifier.rs`
- Update `CallRequest` struct to use `BlockIdentifierOrHash` instead of
`BlockIdentifier` in `transaction.rs`

## Test plan
- [x] `cargo build -p ethrex-rpc` passes
- [x] `cargo test -p ethrex-rpc` passes (46 tests)

Author: jrchatruc

crates/networking/rpc/eth/transaction.rs

@@ -4,7 +4,7 @@ use crate::{
     eth::block,
     rpc::{RpcApiContext, RpcHandler},
     types::{
-        block_identifier::BlockIdentifier,
+        block_identifier::{BlockIdentifier, BlockIdentifierOrHash},
         transaction::{RpcTransaction, SendRawTransactionRequest},
     },
     utils::RpcErr,
@@ -30,7 +30,7 @@ pub const TRANSACTION_GAS: u64 = 21_000; // Per transaction not creating a contr
 
 pub struct CallRequest {
     transaction: GenericTransaction,
-    block: Option<BlockIdentifier>,
+    block: Option<BlockIdentifierOrHash>,
 }
 
 pub struct GetTransactionByBlockNumberAndIndexRequest {
@@ -90,7 +90,7 @@ impl RpcHandler for CallRequest {
         }
         let block = match params.get(1) {
             // Differentiate between missing and bad block param
-            Some(value) => Some(BlockIdentifier::parse(value.clone(), 1)?),
+            Some(value) => Some(BlockIdentifierOrHash::parse(value.clone(), 1)?),
             None => None,
         };
         Ok(CallRequest {
@@ -99,7 +99,10 @@ impl RpcHandler for CallRequest {
         })
     }
     async fn handle(&self, context: RpcApiContext) -> Result<Value, RpcErr> {
-        let block = self.block.clone().unwrap_or_default();
+        let block = self
+            .block
+            .clone()
+            .unwrap_or(BlockIdentifierOrHash::Identifier(BlockIdentifier::default()));
         debug!("Requested call on block: {}", block);
         let header = match block.resolve_block_header(&context.storage).await? {
             Some(header) => header,

crates/networking/rpc/types/block_identifier.rs

@@ -90,7 +90,16 @@ impl BlockIdentifier {
 }
 
 impl BlockIdentifierOrHash {
-    #[allow(unused)]
+    pub async fn resolve_block_header(
+        &self,
+        storage: &Store,
+    ) -> Result<Option<BlockHeader>, StoreError> {
+        match self.resolve_block_number(storage).await? {
+            Some(block_number) => storage.get_block_header(block_number),
+            _ => Ok(None),
+        }
+    }
+
     pub async fn resolve_block_number(
         &self,
         storage: &Store,