More proposer shuffling cleanup

beacon_node/beacon_chain/src/beacon_chain.rs

@@ -6624,11 +6624,12 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             }
 
             let proposers = state.get_beacon_proposer_indices(proposal_epoch, &self.spec)?;
-            Ok::<_, E>(EpochBlockProposers::new(
-                proposal_epoch,
-                state.fork(),
-                proposers,
-            ))
+
+            // Use fork_at_epoch rather than the state's fork, because post-Fulu we may not have
+            // advanced the state completely into the new epoch.
+            let fork = self.spec.fork_at_epoch(proposal_epoch);
+
+            Ok::<_, E>(EpochBlockProposers::new(proposal_epoch, fork, proposers))
         })?;
 
         // Run the accessor function on the computed epoch proposers.

beacon_node/beacon_chain/src/beacon_proposer_cache.rs

@@ -203,7 +203,11 @@ pub fn compute_proposer_duties_from_head<T: BeaconChainTypes>(
         .proposer_shuffling_decision_root_at_epoch(request_epoch, head_block_root, &chain.spec)
         .map_err(BeaconChainError::from)?;
 
-    Ok((indices, dependent_root, execution_status, state.fork()))
+    // Use fork_at_epoch rather than the state's fork, because post-Fulu we may not have advanced
+    // the state completely into the new epoch.
+    let fork = chain.spec.fork_at_epoch(request_epoch);
+
+    Ok((indices, dependent_root, execution_status, fork))
 }
 
 /// If required, advance `state` to the epoch required to determine proposer indices in `target_epoch`.
@@ -235,14 +239,6 @@ pub fn ensure_state_can_determine_proposers_for_epoch<E: EthSpec>(
     if state.current_epoch() > maximum_epoch {
         Err(BeaconStateError::SlotOutOfBounds.into())
     } else if state.current_epoch() >= minimum_epoch {
-        if target_epoch > state.current_epoch() {
-            let target_slot = target_epoch.start_slot(E::slots_per_epoch());
-
-            // Advance the state into the same epoch as the block. Use the "partial" method since state
-            // roots are not important for proposer/attester shuffling.
-            partial_state_advance(state, Some(state_root), target_slot, spec)
-                .map_err(BeaconChainError::from)?;
-        }
         Ok(())
     } else {
         // State's current epoch is less than the minimum epoch.