From 5d01c7b035a2a240d0d5cb8875611ce404e5faa1 Mon Sep 17 00:00:00 2001
From: Yin Guanhao <sopium@mysterious.site>
Date: Tue, 5 Dec 2023 13:04:35 +0800
Subject: [PATCH] Use derived decode and abi/selector for Panic

---
 crates/relayer/src/chain/axon/eth_err.rs | 21 ++++++++-------------
 crates/relayer/src/chain/axon/utils.rs   |  4 ++--
 2 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/crates/relayer/src/chain/axon/eth_err.rs b/crates/relayer/src/chain/axon/eth_err.rs
index dbc4a3f31..140d2c9a9 100644
--- a/crates/relayer/src/chain/axon/eth_err.rs
+++ b/crates/relayer/src/chain/axon/eth_err.rs
@@ -1,17 +1,12 @@
-use ethers::abi::{Detokenize, ParamType, Uint};
+use ethers::abi::Uint;
+use ethers::contract::EthCall;
 
-/// Panic(uint)
+/// For decoding and displaying `Panic(uint256)` errors.
+///
+/// EthError derived decode_with_selector is buggy, so we derive `EthCall` instead. Decode with `AbiDecode::decode`.
+#[derive(EthCall)]
 pub struct Panic(Uint);
 
-impl Panic {
-    // Can't get the right selector with `derive(EthError)`, so I implement this manually.
-    pub fn decode_with_selector(bytes: &[u8]) -> Option<Self> {
-        let bytes = bytes.strip_prefix(b"\x4e\x48\x7b\x71")?;
-        let tokens = ethers::abi::decode(&[ParamType::Uint(32)], bytes).ok()?;
-        Some(Panic(Uint::from_tokens(tokens).ok()?))
-    }
-}
-
 impl std::fmt::Display for Panic {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let e = PanicError::from_code(self.0.low_u32());
@@ -74,7 +69,7 @@ impl std::fmt::Display for PanicError {
 
 #[cfg(test)]
 mod test {
-    use ethers::contract::EthError;
+    use ethers::{abi::AbiDecode, contract::EthError};
 
     use super::Panic;
 
@@ -84,7 +79,7 @@ mod test {
                 .unwrap(),
         )
         .unwrap();
-        if let Some(p) = Panic::decode_with_selector(&revert_data) {
+        if let Ok(p) = Panic::decode(&revert_data) {
             p.to_string()
         } else if let Some(s) = String::decode_with_selector(&revert_data) {
             s
diff --git a/crates/relayer/src/chain/axon/utils.rs b/crates/relayer/src/chain/axon/utils.rs
index 05adb88ba..bdac2b7b5 100644
--- a/crates/relayer/src/chain/axon/utils.rs
+++ b/crates/relayer/src/chain/axon/utils.rs
@@ -10,7 +10,7 @@ use crate::{
     event::IbcEventWithHeight,
     ibc_contract::OwnableIBCHandlerEvents,
 };
-use ethers::{contract::ContractError, providers::Middleware, types::H256};
+use ethers::{abi::AbiDecode, contract::ContractError, providers::Middleware, types::H256};
 use ibc_relayer_types::{
     clients::{
         ics07_axon::{client_state::AxonClientState, consensus_state::AxonConsensusState},
@@ -35,7 +35,7 @@ where
 {
     if let Some(r) = err.decode_revert::<String>() {
         eyre::eyre!("Contract call reverted: {r}")
-    } else if let Some(p) = err.as_revert().and_then(|d| Panic::decode_with_selector(d)) {
+    } else if let Some(p) = err.as_revert().and_then(|d| Panic::decode(d).ok()) {
         eyre::eyre!("Contract call reverted: {p}")
     } else {
         err.into()