From b8f0b5d67e3e9f25b024667e6024ce98aeb907ba Mon Sep 17 00:00:00 2001
From: gustavo <1gusredo@gmail.com>
Date: Thu, 4 Dec 2025 15:43:42 +0000
Subject: [PATCH] fix(rpc): improve/preserve error messages for
 TransactionConversionError (#20057)

---
 crates/rpc/rpc-convert/src/transaction.rs         | 15 ++++++++++-----
 crates/rpc/rpc-eth-api/src/helpers/transaction.rs |  6 ++++--
 crates/rpc/rpc-eth-types/src/error/mod.rs         | 12 +++---------
 3 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/crates/rpc/rpc-convert/src/transaction.rs b/crates/rpc/rpc-convert/src/transaction.rs
index f07d96aeb5..1036e15199 100644
--- a/crates/rpc/rpc-convert/src/transaction.rs
+++ b/crates/rpc/rpc-convert/src/transaction.rs
@@ -16,7 +16,6 @@ use reth_primitives_traits::{
     TxTy,
 };
 use std::{convert::Infallible, error::Error, fmt::Debug, marker::PhantomData};
-use thiserror::Error;
 
 /// Input for [`RpcConvert::convert_receipts`].
 #[derive(Debug, Clone)]
@@ -484,10 +483,16 @@ where
 }
 
 /// Conversion into transaction RPC response failed.
-#[derive(Debug, Clone, Error)]
-#[error("Failed to convert transaction into RPC response: {0}")]
-pub struct TransactionConversionError(String);
+#[derive(Debug, thiserror::Error)]
+pub enum TransactionConversionError {
+    /// Required fields are missing from the transaction request.
+    #[error("Failed to convert transaction into RPC response: {0}")]
+    FromTxReq(String),
 
+    /// Other conversion errors.
+    #[error("{0}")]
+    Other(String),
+}
 /// Generic RPC response object converter for `Evm` and network `Network`.
 ///
 /// The main purpose of this struct is to provide an implementation of [`RpcConvert`] for generic
@@ -826,7 +831,7 @@ where
         Ok(self
             .sim_tx_converter
             .convert_sim_tx(request)
-            .map_err(|e| TransactionConversionError(e.to_string()))?)
+            .map_err(|e| TransactionConversionError::FromTxReq(e.to_string()))?)
     }
 
     fn tx_env(
diff --git a/crates/rpc/rpc-eth-api/src/helpers/transaction.rs b/crates/rpc/rpc-eth-api/src/helpers/transaction.rs
index 6bff6c42e9..4256a55230 100644
--- a/crates/rpc/rpc-eth-api/src/helpers/transaction.rs
+++ b/crates/rpc/rpc-eth-api/src/helpers/transaction.rs
@@ -20,7 +20,7 @@ use futures::{Future, StreamExt};
 use reth_chain_state::CanonStateSubscriptions;
 use reth_node_api::BlockBody;
 use reth_primitives_traits::{Recovered, RecoveredBlock, SignedTransaction, TxTy, WithEncoded};
-use reth_rpc_convert::{transaction::RpcConvert, RpcTxReq};
+use reth_rpc_convert::{transaction::RpcConvert, RpcTxReq, TransactionConversionError};
 use reth_rpc_eth_types::{
     utils::{binary_search, recover_raw_transaction},
     EthApiError::{self, TransactionConfirmationTimeout},
@@ -433,7 +433,9 @@ pub trait EthTransactions: LoadTransaction<Provider: BlockReaderIdExt> {
                 <<Self as RpcNodeCore>::Pool as TransactionPool>::Transaction::try_from_consensus(
                     transaction,
                 )
-                .map_err(|_| EthApiError::TransactionConversionError)?;
+                .map_err(|e| {
+                    Self::Error::from_eth_err(TransactionConversionError::Other(e.to_string()))
+                })?;
 
             // submit the transaction to the pool with a `Local` origin
             let AddedTransactionOutcome { hash, .. } = self
diff --git a/crates/rpc/rpc-eth-types/src/error/mod.rs b/crates/rpc/rpc-eth-types/src/error/mod.rs
index 641bfbc84f..dd0fcd8647 100644
--- a/crates/rpc/rpc-eth-types/src/error/mod.rs
+++ b/crates/rpc/rpc-eth-types/src/error/mod.rs
@@ -164,8 +164,8 @@ pub enum EthApiError {
     #[error("Invalid bytecode: {0}")]
     InvalidBytecode(String),
     /// Error encountered when converting a transaction type
-    #[error("Transaction conversion error")]
-    TransactionConversionError,
+    #[error(transparent)]
+    TransactionConversionError(#[from] TransactionConversionError),
     /// Error thrown when tracing with a muxTracer fails
     #[error(transparent)]
     MuxTracerError(#[from] MuxError),
@@ -273,7 +273,7 @@ impl From<EthApiError> for jsonrpsee_types::error::ErrorObject<'static> {
             EthApiError::Signing(_) |
             EthApiError::BothStateAndStateDiffInOverride(_) |
             EthApiError::InvalidTracerConfig |
-            EthApiError::TransactionConversionError |
+            EthApiError::TransactionConversionError(_) |
             EthApiError::InvalidRewardPercentiles |
             EthApiError::InvalidBytecode(_) => invalid_params_rpc_err(error.to_string()),
             EthApiError::InvalidTransaction(err) => err.into(),
@@ -336,12 +336,6 @@ impl From<EthApiError> for jsonrpsee_types::error::ErrorObject<'static> {
     }
 }
 
-impl From<TransactionConversionError> for EthApiError {
-    fn from(_: TransactionConversionError) -> Self {
-        Self::TransactionConversionError
-    }
-}
-
 impl<E> From<CallError<E>> for EthApiError
 where
     E: Into<Self>,