From f78f0302f10e4c087b306daf92aba40540bad881 Mon Sep 17 00:00:00 2001
From: Matthias Seitz <matthias.seitz@outlook.de>
Date: Fri, 14 Jul 2023 09:59:57 +0200
Subject: [PATCH] fix(rpc): serialize traces always as vec (#3770)

---
 .../revm/revm-inspectors/src/tracing/builder/parity.rs   | 7 ++++++-
 crates/rpc/rpc-types/src/eth/trace/parity.rs             | 9 +++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/crates/revm/revm-inspectors/src/tracing/builder/parity.rs b/crates/revm/revm-inspectors/src/tracing/builder/parity.rs
index ba73f6cef0..cce86c4344 100644
--- a/crates/revm/revm-inspectors/src/tracing/builder/parity.rs
+++ b/crates/revm/revm-inspectors/src/tracing/builder/parity.rs
@@ -138,7 +138,12 @@ impl ParityTraceBuilder {
 
         let (trace, vm_trace, state_diff) = self.into_trace_type_traces(trace_types);
 
-        TraceResults { output: output.into(), trace, vm_trace, state_diff }
+        TraceResults {
+            output: output.into(),
+            trace: trace.unwrap_or_default(),
+            vm_trace,
+            state_diff,
+        }
     }
 
     /// Consumes the inspector and returns the trace results according to the configured trace
diff --git a/crates/rpc/rpc-types/src/eth/trace/parity.rs b/crates/rpc/rpc-types/src/eth/trace/parity.rs
index 7fbea1bbac..fcc5e54bbb 100644
--- a/crates/rpc/rpc-types/src/eth/trace/parity.rs
+++ b/crates/rpc/rpc-types/src/eth/trace/parity.rs
@@ -30,12 +30,13 @@ pub enum TraceType {
 pub struct TraceResults {
     /// Output of the trace
     pub output: Bytes,
-    /// Enabled if [TraceType::Trace] is provided
-    pub trace: Option<Vec<TransactionTrace>>,
-    /// Enabled if [TraceType::VmTrace] is provided
-    pub vm_trace: Option<VmTrace>,
     /// Enabled if [TraceType::StateDiff] is provided
     pub state_diff: Option<StateDiff>,
+    /// Enabled if [TraceType::Trace] is provided, otherwise an empty vec
+    #[serde(default)]
+    pub trace: Vec<TransactionTrace>,
+    /// Enabled if [TraceType::VmTrace] is provided
+    pub vm_trace: Option<VmTrace>,
 }
 
 /// A `FullTrace` with an additional transaction hash