feat: pass parent beacon block root to payload builder (paradigmxyz#4425

)

crates/payload/basic/src/lib.rs

@@ -828,7 +828,7 @@ where
         difficulty: U256::ZERO,
         gas_used: cumulative_gas_used,
         extra_data: extra_data.into(),
-        parent_beacon_block_root: None,
+        parent_beacon_block_root: attributes.parent_beacon_block_root,
         blob_gas_used,
         excess_blob_gas,
     };
@@ -906,7 +906,7 @@ where
         blob_gas_used: None,
         excess_blob_gas: None,
         extra_data: extra_data.into(),
-        parent_beacon_block_root: None,
+        parent_beacon_block_root: attributes.parent_beacon_block_root,
     };
 
     let block = Block { header, body: vec![], ommers: vec![], withdrawals };

crates/payload/builder/src/payload.rs

@@ -129,6 +129,8 @@ pub struct PayloadBuilderAttributes {
     pub prev_randao: H256,
     /// Withdrawals for the generated payload
     pub withdrawals: Vec<Withdrawal>,
+    /// Root of the parent beacon block
+    pub parent_beacon_block_root: Option<H256>,
 }
 
 // === impl PayloadBuilderAttributes ===
@@ -146,6 +148,7 @@ impl PayloadBuilderAttributes {
             suggested_fee_recipient: attributes.suggested_fee_recipient,
             prev_randao: attributes.prev_randao,
             withdrawals: attributes.withdrawals.unwrap_or_default(),
+            parent_beacon_block_root: attributes.parent_beacon_block_root,
         }
     }
 
@@ -204,6 +207,9 @@ pub(crate) fn payload_id(parent: &H256, attributes: &PayloadAttributes) -> Paylo
         withdrawals.encode(&mut buf);
         hasher.update(buf);
     }
+    if let Some(parent_beacon_block) = attributes.parent_beacon_block_root {
+        hasher.update(parent_beacon_block);
+    }
     let out = hasher.finalize();
     PayloadId::new(out.as_slice()[..8].try_into().expect("sufficient length"))
 }