From 08c68beef374e7a984dc329c89d69a7f8d64fcdb Mon Sep 17 00:00:00 2001
From: Wolfgang Welz <welzwo@gmail.com>
Date: Wed, 11 Sep 2024 23:11:40 +0200
Subject: [PATCH 1/4] return error on empty accounts

---
 steel/src/host/db/proof.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/steel/src/host/db/proof.rs b/steel/src/host/db/proof.rs
index 241c7f18..54748b26 100644
--- a/steel/src/host/db/proof.rs
+++ b/steel/src/host/db/proof.rs
@@ -140,8 +140,9 @@ impl<T: Transport + Clone, N: Network, P: Provider<T, N>> ProofDb<AlloyDb<T, N,
     /// Returns the merkle proofs (sparse [MerkleTrie]) for the state and all storage queries
     /// recorded by the [Database].
     pub async fn state_proof(&mut self) -> Result<(MerkleTrie, Vec<MerkleTrie>)> {
-        let proofs = &mut self.proofs;
+        ensure!(!self.accounts.is_empty(), "no accounts accessed: use Contract::preflight");
 
+        let proofs = &mut self.proofs;
         for (address, storage_keys) in &self.accounts {
             let account_proof = proofs.get(address);
             let storage_keys: Vec<_> = storage_keys

From df3d33f27a6835f1a34cfe1fd000841a43ce0c63 Mon Sep 17 00:00:00 2001
From: Wolfgang Welz <welzwo@gmail.com>
Date: Wed, 11 Sep 2024 23:14:31 +0200
Subject: [PATCH 2/4] update CHANGELOG

---
 steel/CHANGELOG.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/steel/CHANGELOG.md b/steel/CHANGELOG.md
index 5d49cf74..828c567c 100644
--- a/steel/CHANGELOG.md
+++ b/steel/CHANGELOG.md
@@ -6,6 +6,10 @@ All notable changes to this project will be documented in this file.
 
 ### ⚡️ Features
 
+### 🛠 Fixes
+
+- Return specific error, when no `Contract::preflight` was called.
+
 ### 🚨 Breaking Changes
 
 ## [0.13.0](https://github.com/risc0/risc0-ethereum/releases/tag/steel-v0.13.0) - 2024-09-10

From 9c736e334e872c3bbd5b7b8ea3ab6f50a5eeb569 Mon Sep 17 00:00:00 2001
From: Wolfgang Welz <welzwo@gmail.com>
Date: Wed, 11 Sep 2024 23:28:29 +0200
Subject: [PATCH 3/4] add test

---
 steel/src/host/db/proof.rs |  5 ++++-
 steel/tests/steel.rs       | 14 ++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/steel/src/host/db/proof.rs b/steel/src/host/db/proof.rs
index 54748b26..4a343a51 100644
--- a/steel/src/host/db/proof.rs
+++ b/steel/src/host/db/proof.rs
@@ -140,7 +140,10 @@ impl<T: Transport + Clone, N: Network, P: Provider<T, N>> ProofDb<AlloyDb<T, N,
     /// Returns the merkle proofs (sparse [MerkleTrie]) for the state and all storage queries
     /// recorded by the [Database].
     pub async fn state_proof(&mut self) -> Result<(MerkleTrie, Vec<MerkleTrie>)> {
-        ensure!(!self.accounts.is_empty(), "no accounts accessed: use Contract::preflight");
+        ensure!(
+            !self.accounts.is_empty(),
+            "no accounts accessed: use Contract::preflight"
+        );
 
         let proofs = &mut self.proofs;
         for (address, storage_keys) in &self.accounts {
diff --git a/steel/tests/steel.rs b/steel/tests/steel.rs
index 35835c13..d829a02a 100644
--- a/steel/tests/steel.rs
+++ b/steel/tests/steel.rs
@@ -324,6 +324,20 @@ async fn call_eoa() {
         .expect_err("calling an EOA should fail");
 }
 
+#[test(tokio::test)]
+async fn no_preflight() {
+    let env = EthEvmEnv::builder()
+        .provider(test_provider().await)
+        .build()
+        .await
+        .unwrap()
+        .with_chain_spec(&ANVIL_CHAIN_SPEC);
+    match env.into_input().await {
+        Ok(_) => panic!("calling into_input without a preflight should fail"),
+        Err(err) => assert_eq!(err.to_string(), "no accounts accessed: use Contract::preflight"),
+    }
+}
+
 alloy::sol!(
     // docker run -i ethereum/solc:0.8.26 - --optimize --bin
     #[sol(rpc, bytecode="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")]

From 53f5a77e6eacc5abded2fa1268123fabac23457c Mon Sep 17 00:00:00 2001
From: Wolfgang Welz <welzwo@gmail.com>
Date: Wed, 11 Sep 2024 23:33:28 +0200
Subject: [PATCH 4/4] fix fmt

---
 steel/tests/steel.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/steel/tests/steel.rs b/steel/tests/steel.rs
index d829a02a..220c7fee 100644
--- a/steel/tests/steel.rs
+++ b/steel/tests/steel.rs
@@ -334,7 +334,10 @@ async fn no_preflight() {
         .with_chain_spec(&ANVIL_CHAIN_SPEC);
     match env.into_input().await {
         Ok(_) => panic!("calling into_input without a preflight should fail"),
-        Err(err) => assert_eq!(err.to_string(), "no accounts accessed: use Contract::preflight"),
+        Err(err) => assert_eq!(
+            err.to_string(),
+            "no accounts accessed: use Contract::preflight"
+        ),
     }
 }