fix(eth): serialize empty lists as [] instead of null

CHANGELOG.md

@@ -53,6 +53,8 @@
 
 - [#6975](https://github.com/ChainSafe/forest/issues/6975): Fixed `Filecoin.MpoolSelect` to not remove the messages from the live pool, only simulate the head change.
 
+- [#7205](https://github.com/ChainSafe/forest/issues/7205): Fixed eth methods serializing empty lists as `null` instead of `[]`.
+
 ## Forest v0.33.6 "Ebb"
 
 Non-mandatory release for all node operators. It fixes a critical memory leak in `v0.33.5`. (Earlier releases are not affected)

src/lotus_json/vec.rs

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0, MIT
 
 use super::*;
+use get_size2::GetSize;
 
 impl<T> HasLotusJson for Vec<T>
 // TODO(forest): https://github.com/ChainSafe/forest/issues/4032
@@ -37,7 +38,7 @@ where
 // while an empty `NotNullVec<T>` serializes into `[]`
 // this is a temporary workaround and will likely be deprecated once
 // other issues on serde of `Vec<T>` are resolved.
-#[derive(Debug, Clone, PartialEq, JsonSchema)]
+#[derive(Debug, Clone, Default, PartialEq, JsonSchema, GetSize)]
 pub struct NotNullVec<T>(pub Vec<T>);
 
 impl<T> HasLotusJson for NotNullVec<T>

src/rpc/methods/eth.rs

@@ -26,7 +26,7 @@ use crate::eth::{
     EAMMethod, EVMMethod, EthChainId as EthChainIdType, EthEip1559TxArgs, EthLegacyEip155TxArgs,
     EthLegacyHomesteadTxArgs, parse_eth_transaction,
 };
-use crate::lotus_json::{HasLotusJson, lotus_json_with_self};
+use crate::lotus_json::{HasLotusJson, NotNullVec, lotus_json_with_self};
 use crate::message::{ChainMessage, MessageRead as _, MessageReadWrite as _, SignedMessage};
 use crate::networks::Height;
 use crate::prelude::*;
@@ -644,7 +644,7 @@ pub struct ApiEthTx {
     pub gas_price: Option<EthBigInt>,
     #[schemars(with = "Option<Vec<EthHash>>")]
     #[serde(with = "crate::lotus_json")]
-    pub access_list: Vec<EthHash>,
+    pub access_list: Option<NotNullVec<EthHash>>,
     pub v: EthBigInt,
     pub r: EthBigInt,
     pub s: EthBigInt,
@@ -846,15 +846,15 @@ impl RpcMethod<0> for EthAccounts {
     );
 
     type Params = ();
-    type Ok = Vec<String>;
+    type Ok = NotNullVec<String>;
 
     async fn handle(
         _: Ctx,
         (): Self::Params,
         _: &http::Extensions,
     ) -> Result<Self::Ok, ServerError> {
         // EthAccounts will always return [] since we don't expect Forest to manage private keys
-        Ok(vec![])
+        Ok(NotNullVec(vec![]))
     }
 }
 
@@ -1263,7 +1263,7 @@ fn eth_tx_from_native_message<DB: Blockstore>(
         gas: EthUint64(msg.gas_limit),
         max_fee_per_gas: Some(msg.gas_fee_cap.clone().into()),
         max_priority_fee_per_gas: Some(msg.gas_premium.clone().into()),
-        access_list: vec![],
+        access_list: Some(NotNullVec(vec![])),
         ..ApiEthTx::default()
     })
 }
@@ -1602,7 +1602,7 @@ impl RpcMethod<1> for EthGetBlockReceipts {
     );
 
     type Params = (BlockNumberOrHash,);
-    type Ok = Vec<EthTxReceipt>;
+    type Ok = NotNullVec<EthTxReceipt>;
 
     async fn handle(
         ctx: Ctx,
@@ -1615,6 +1615,7 @@ impl RpcMethod<1> for EthGetBlockReceipts {
             .await?;
         get_block_receipts(&ctx, ts, None)
             .await
+            .map(NotNullVec)
             .map_err(ServerError::from)
     }
 }
@@ -1631,7 +1632,7 @@ impl RpcMethod<2> for EthGetBlockReceiptsLimited {
     );
 
     type Params = (BlockNumberOrHash, ChainEpoch);
-    type Ok = Vec<EthTxReceipt>;
+    type Ok = NotNullVec<EthTxReceipt>;
 
     async fn handle(
         ctx: Ctx,
@@ -1644,6 +1645,7 @@ impl RpcMethod<2> for EthGetBlockReceiptsLimited {
             .await?;
         get_block_receipts(&ctx, ts, Some(limit))
             .await
+            .map(NotNullVec)
             .map_err(ServerError::from)
     }
 }
@@ -3572,7 +3574,7 @@ impl RpcMethod<1> for EthTraceBlock {
     const DESCRIPTION: Option<&'static str> = Some("Returns traces created at given block.");
 
     type Params = (BlockNumberOrHash,);
-    type Ok = Vec<EthBlockTrace>;
+    type Ok = NotNullVec<EthBlockTrace>;
     async fn handle(
         ctx: Ctx,
         (block_param,): Self::Params,
@@ -3582,7 +3584,9 @@ impl RpcMethod<1> for EthTraceBlock {
         let ts = resolver
             .tipset_by_block_number_or_hash(block_param, ResolveNullTipset::TakeOlder)
             .await?;
-        eth_trace_block(&ctx.state_manager, &ts).await
+        eth_trace_block(&ctx.state_manager, &ts)
+            .await
+            .map(NotNullVec)
     }
 }
 
@@ -3971,7 +3975,7 @@ impl RpcMethod<1> for EthTraceTransaction {
         Some("Returns the traces for a specific transaction.");
 
     type Params = (String,);
-    type Ok = Vec<EthBlockTrace>;
+    type Ok = NotNullVec<EthBlockTrace>;
     async fn handle(
         ctx: Ctx,
         (tx_hash,): Self::Params,
@@ -3992,7 +3996,7 @@ impl RpcMethod<1> for EthTraceTransaction {
             .into_iter()
             .filter(|trace| trace.transaction_hash == eth_hash)
             .collect();
-        Ok(traces)
+        Ok(NotNullVec(traces))
     }
 }
 
@@ -4009,7 +4013,7 @@ impl RpcMethod<2> for EthTraceReplayBlockTransactions {
     );
 
     type Params = (BlockNumberOrHash, Vec<String>);
-    type Ok = Vec<EthReplayBlockTransactionTrace>;
+    type Ok = NotNullVec<EthReplayBlockTransactionTrace>;
 
     async fn handle(
         ctx: Ctx,
@@ -4028,7 +4032,9 @@ impl RpcMethod<2> for EthTraceReplayBlockTransactions {
             .tipset_by_block_number_or_hash(block_param, ResolveNullTipset::TakeOlder)
             .await?;
 
-        eth_trace_replay_block_transactions(&ctx, &ts).await
+        eth_trace_replay_block_transactions(&ctx, &ts)
+            .await
+            .map(NotNullVec)
     }
 }
 
@@ -4081,7 +4087,7 @@ impl RpcMethod<1> for EthTraceFilter {
     const DESCRIPTION: Option<&'static str> =
         Some("Returns the traces for transactions matching the filter criteria.");
     type Params = (EthTraceFilterCriteria,);
-    type Ok = Vec<EthBlockTrace>;
+    type Ok = NotNullVec<EthBlockTrace>;
 
     async fn handle(
         ctx: Ctx,
@@ -4115,7 +4121,9 @@ impl RpcMethod<1> for EthTraceFilter {
                 return Err(EthErrors::limit_exceeded(max_block_range, range).into());
             }
         }
-        Ok(trace_filter(ctx, filter, from_block, to_block, ext).await?)
+        Ok(NotNullVec(
+            trace_filter(ctx, filter, from_block, to_block, ext).await?,
+        ))
     }
 }
 
@@ -4147,7 +4155,7 @@ async fn trace_filter(
             ext,
         )
         .await?;
-        for block_trace in block_traces {
+        for block_trace in block_traces.0 {
             if block_trace
                 .trace
                 .match_filter_criteria(filter.from_address.as_ref(), filter.to_address.as_ref())?
@@ -4201,6 +4209,27 @@ mod test {
         }
     }
 
+    #[test]
+    fn empty_access_list_serializes_as_empty_array() {
+        let tx = ApiEthTx {
+            access_list: Some(NotNullVec(vec![])),
+            ..Default::default()
+        };
+        let json = serde_json::to_value(tx.into_lotus_json()).unwrap();
+        assert_eq!(json["accessList"], serde_json::json!([]));
+    }
+
+    #[test]
+    fn populated_access_list_serializes_as_array() {
+        let tx = ApiEthTx {
+            access_list: Some(NotNullVec(vec![EthHash::default()])),
+            ..Default::default()
+        };
+        let json = serde_json::to_value(tx.into_lotus_json()).unwrap();
+        assert!(json["accessList"].is_array());
+        assert_eq!(json["accessList"].as_array().unwrap().len(), 1);
+    }
+
     #[quickcheck]
     fn gas_price_result_serde_roundtrip(i: u128) {
         let r = EthBigInt(ethereum_types::U256::from(i));