fix: allow withdrawal root past shanghai (#1437)

crates/consensus/src/validation.rs

@@ -50,7 +50,9 @@ pub fn validate_header_standalone(
         header.withdrawals_root.is_none()
     {
         return Err(Error::WithdrawalsRootMissing)
-    } else if header.withdrawals_root.is_some() {
+    } else if !chain_spec.fork(Hardfork::Shanghai).active_at_timestamp(header.timestamp) &&
+        header.withdrawals_root.is_some()
+    {
         return Err(Error::WithdrawalsRootUnexpected)
     }
 
@@ -334,7 +336,7 @@ pub fn validate_header_regarding_parent(
 ///  If we already know the block.
 ///  If parent is known
 ///
-/// Returns parent block header  
+/// Returns parent block header
 pub fn validate_block_regarding_chain<PROV: HeaderProvider>(
     block: &SealedBlock,
     provider: &PROV,
@@ -638,4 +640,20 @@ mod tests {
             Err(Error::WithdrawalIndexInvalid { .. })
         );
     }
+
+    #[test]
+    fn shanghai_block_zero_withdrawals() {
+        // ensures that if shanghai is activated, and we include a block with a withdrawals root,
+        // that the header is valid
+        let chain_spec = ChainSpecBuilder::mainnet().shanghai_activated().build();
+
+        let header = Header {
+            base_fee_per_gas: Some(1337u64.into()),
+            withdrawals_root: Some(proofs::calculate_withdrawals_root(&[])),
+            ..Default::default()
+        }
+        .seal_slow();
+
+        assert_eq!(validate_header_standalone(&header, &chain_spec), Ok(()));
+    }
 }