refactor bellatrix::ExecutionEngine

drop extra implementations we don't necessary need
lay the ground work for future forks' implementation

ethereum-consensus/examples/sketch.rs

@@ -40,11 +40,11 @@ fn main() {
     let current_epoch = bellatrix::get_current_epoch(&state, &context);
     dbg!(current_epoch);
 
-    let execution_engine = bellatrix::NoOpExecutionEngine;
+    let execution_engine = bellatrix::DefaultExecutionEngine::default();
     let _ = bellatrix::state_transition(
         &mut state,
         &mut signed_block,
-        execution_engine,
+        &execution_engine,
         Validation::Enabled,
         &context,
     );

ethereum-consensus/examples/state_transition_across_multiple_forks.rs

@@ -1,8 +1,8 @@
 use ethereum_consensus::{
     altair::mainnet as altair,
-    bellatrix::{mainnet as bellatrix, NoOpExecutionEngine},
+    bellatrix::mainnet as bellatrix,
     phase0::mainnet as phase0,
-    state_transition::mainnet::{Context, Executor},
+    state_transition::mainnet::{Context, ExecutionEngine, Executor},
 };
 use ssz_rs::prelude::*;
 use std::error::Error;
@@ -13,7 +13,8 @@ fn main() -> std::result::Result<(), Box<dyn Error>> {
 
     let genesis_state = phase0::BeaconState::default();
     let context = Context::for_mainnet();
-    let mut executor = Executor::new(genesis_state.into(), NoOpExecutionEngine, context);
+    let execution_engine = ExecutionEngine::Bellatrix(bellatrix::DefaultExecutionEngine::default());
+    let mut executor = Executor::new(genesis_state.into(), execution_engine, context);
 
     let mut block = phase0::SignedBeaconBlock::default();
     block.message.slot = 1;

ethereum-consensus/src/bellatrix/block_processing.rs

@@ -3,7 +3,7 @@ use crate::{
         compute_timestamp_at_slot, get_current_epoch, get_randao_mix, is_execution_enabled,
         is_merge_transition_complete, process_block_header, process_eth1_data, process_operations,
         process_randao, process_sync_aggregate, BeaconBlock, BeaconState, ExecutionEngine,
-        ExecutionPayload, ExecutionPayloadHeader,
+        ExecutionPayload, ExecutionPayloadHeader, NewPayloadRequest,
     },
     state_transition::{invalid_operation_error, Context, InvalidExecutionPayload, Result},
 };
@@ -47,7 +47,7 @@ pub fn process_execution_payload<
         MAX_BYTES_PER_TRANSACTION,
         MAX_TRANSACTIONS_PER_PAYLOAD,
     >,
-    execution_engine: E,
+    execution_engine: &E,
     context: &Context,
 ) -> Result<()> {
     let parent_hash_invalid =
@@ -85,7 +85,8 @@ pub fn process_execution_payload<
         ))
     }
 
-    execution_engine.notify_new_payload(payload)?;
+    let new_payload_request = NewPayloadRequest(payload);
+    execution_engine.verify_and_notify_new_payload(&new_payload_request)?;
 
     state.latest_execution_payload_header = ExecutionPayloadHeader {
         parent_hash: payload.parent_hash.clone(),
@@ -157,7 +158,7 @@ pub fn process_block<
         MAX_BYTES_PER_TRANSACTION,
         MAX_TRANSACTIONS_PER_PAYLOAD,
     >,
-    execution_engine: E,
+    execution_engine: &E,
     context: &Context,
 ) -> Result<()> {
     process_block_header(state, block, context)?;