From fa109e3a41bc84ca0721a218003ff3c45dcbc36e Mon Sep 17 00:00:00 2001
From: Matthias Seitz <matthias.seitz@outlook.de>
Date: Fri, 3 Jan 2025 22:15:01 +0100
Subject: [PATCH] feat: add additional conversion fn (#1883)

---
 crates/rpc-types-engine/src/payload.rs | 44 +++++++++++++++++++++++++-
 crates/rpc-types-engine/src/sidecar.rs | 27 ++++++++++++++++
 2 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/crates/rpc-types-engine/src/payload.rs b/crates/rpc-types-engine/src/payload.rs
index 937b6836537..94b5a0c6f02 100644
--- a/crates/rpc-types-engine/src/payload.rs
+++ b/crates/rpc-types-engine/src/payload.rs
@@ -6,7 +6,7 @@ use alloc::{
     vec::Vec,
 };
 use alloy_consensus::{
-    constants::MAXIMUM_EXTRA_DATA_SIZE, Blob, Block, BlockBody, Bytes48, Header,
+    constants::MAXIMUM_EXTRA_DATA_SIZE, Blob, Block, BlockBody, Bytes48, Header, Transaction,
     EMPTY_OMMER_ROOT_HASH,
 };
 use alloy_eips::{
@@ -770,6 +770,48 @@ pub enum ExecutionPayload {
 }
 
 impl ExecutionPayload {
+    /// Converts [`alloy_consensus::Block`] to [`ExecutionPayload`] and also returns the
+    /// [`ExecutionPayloadSidecar`] extracted from the block.
+    ///
+    /// See also [`ExecutionPayloadV3::from_block_unchecked`].
+    /// See also [`ExecutionPayloadSidecar::from_block`].
+    ///
+    /// Note: This re-calculates the block hash.
+    pub fn from_block_slow<T>(block: &Block<T>) -> (Self, ExecutionPayloadSidecar)
+    where
+        T: Encodable2718 + Transaction,
+    {
+        Self::from_block_unchecked(block.hash_slow(), block)
+    }
+
+    /// Converts [`alloy_consensus::Block`] to [`ExecutionPayload`] and also returns the
+    /// [`ExecutionPayloadSidecar`] extracted from the block.
+    ///
+    /// See also [`ExecutionPayloadV3::from_block_unchecked`].
+    /// See also [`ExecutionPayloadSidecar::from_block`].
+    pub fn from_block_unchecked<T>(
+        block_hash: B256,
+        block: &Block<T>,
+    ) -> (Self, ExecutionPayloadSidecar)
+    where
+        T: Encodable2718 + Transaction,
+    {
+        let sidecar = ExecutionPayloadSidecar::from_block(block);
+
+        let execution_payload = if block.header.parent_beacon_block_root.is_some() {
+            // block with parent beacon block root: V3
+            Self::V3(ExecutionPayloadV3::from_block_unchecked(block_hash, block))
+        } else if block.body.withdrawals.is_some() {
+            // block with withdrawals: V2
+            Self::V2(ExecutionPayloadV2::from_block_unchecked(block_hash, block))
+        } else {
+            // otherwise V1
+            Self::V1(ExecutionPayloadV1::from_block_unchecked(block_hash, block))
+        };
+
+        (execution_payload, sidecar)
+    }
+
     /// Tries to create a new unsealed block from the given payload and payload sidecar.
     ///
     /// Performs additional validation of `extra_data` and `base_fee_per_gas` fields.
diff --git a/crates/rpc-types-engine/src/sidecar.rs b/crates/rpc-types-engine/src/sidecar.rs
index 79db14d3644..c7262d593fb 100644
--- a/crates/rpc-types-engine/src/sidecar.rs
+++ b/crates/rpc-types-engine/src/sidecar.rs
@@ -4,6 +4,7 @@ use crate::{
     CancunPayloadFields, MaybeCancunPayloadFields, MaybePraguePayloadFields, PraguePayloadFields,
 };
 use alloc::vec::Vec;
+use alloy_consensus::{Block, Transaction};
 use alloy_eips::eip7685::Requests;
 use alloy_primitives::B256;
 
@@ -21,6 +22,32 @@ pub struct ExecutionPayloadSidecar {
 }
 
 impl ExecutionPayloadSidecar {
+    /// Extracts the [`ExecutionPayloadSidecar`] from the given [`alloy_consensus::Block`].
+    ///
+    /// Returns [`ExecutionPayloadSidecar::none`] if the block does not contain any sidecar fields
+    /// (pre-cancun): `requests_hash`, `parent_beacon_block_root`, `blob_versioned_hashes`.
+    ///
+    /// Note: This returns [`RequestOrHash::Hash`](alloy_eips::eip7685::RequestsOrHash::Hash) for
+    /// the EIP-7685 requests.
+    pub fn from_block<T>(block: &Block<T>) -> Self
+    where
+        T: Transaction,
+    {
+        let cancun =
+            block.parent_beacon_block_root.map(|parent_beacon_block_root| CancunPayloadFields {
+                parent_beacon_block_root,
+                versioned_hashes: block.body.blob_versioned_hashes_iter().copied().collect(),
+            });
+
+        let prague = block.requests_hash.map(PraguePayloadFields::new);
+
+        match (cancun, prague) {
+            (Some(cancun), Some(prague)) => Self::v4(cancun, prague),
+            (Some(cancun), None) => Self::v3(cancun),
+            _ => Self::none(),
+        }
+    }
+
     /// Returns a new empty instance (pre-cancun, v1, v2)
     pub const fn none() -> Self {
         Self { cancun: MaybeCancunPayloadFields::none(), prague: MaybePraguePayloadFields::none() }