Feature gate withdrawals (#3684)

* start feature gating

* feature gate withdrawals

consensus/state_processing/src/common/mod.rs

@@ -15,6 +15,7 @@ pub use get_attesting_indices::{get_attesting_indices, get_attesting_indices_fro
 pub use get_indexed_attestation::get_indexed_attestation;
 pub use initiate_validator_exit::initiate_validator_exit;
 pub use slash_validator::slash_validator;
+#[cfg(feature = "withdrawals")]
 pub use withdraw_balance::withdraw_balance;
 
 use safe_arith::SafeArith;

consensus/state_processing/src/common/withdraw_balance.rs

@@ -2,6 +2,7 @@ use crate::common::decrease_balance;
 use safe_arith::SafeArith;
 use types::{BeaconStateError as Error, *};
 
+#[cfg(feature = "withdrawals")]
 pub fn withdraw_balance<T: EthSpec>(
     state: &mut BeaconState<T>,
     validator_index: usize,

consensus/state_processing/src/per_epoch_processing/capella.rs

@@ -5,11 +5,15 @@ use crate::per_epoch_processing::{
     historical_roots_update::process_historical_roots_update,
     resets::{process_eth1_data_reset, process_randao_mixes_reset, process_slashings_reset},
 };
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub use full_withdrawals::process_full_withdrawals;
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub use partial_withdrawals::process_partial_withdrawals;
 use types::{BeaconState, ChainSpec, EthSpec, RelativeEpoch};
 
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub mod full_withdrawals;
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub mod partial_withdrawals;
 
 pub fn process_epoch<T: EthSpec>(
@@ -66,8 +70,10 @@ pub fn process_epoch<T: EthSpec>(
     altair::process_sync_committee_updates(state, spec)?;
 
     // Withdrawals
+    #[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
     process_full_withdrawals(state, spec)?;
 
+    #[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
     process_partial_withdrawals(state, spec)?;
 
     // Rotate the epoch caches to suit the epoch transition.

consensus/state_processing/src/per_epoch_processing/capella/full_withdrawals.rs

@@ -1,7 +1,9 @@
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 use crate::common::withdraw_balance;
 use crate::EpochProcessingError;
 use types::{beacon_state::BeaconState, eth_spec::EthSpec, ChainSpec};
 
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub fn process_full_withdrawals<T: EthSpec>(
     state: &mut BeaconState<T>,
     spec: &ChainSpec,

consensus/state_processing/src/per_epoch_processing/capella/partial_withdrawals.rs

@@ -1,8 +1,10 @@
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 use crate::common::withdraw_balance;
 use crate::EpochProcessingError;
 use safe_arith::SafeArith;
 use types::{beacon_state::BeaconState, eth_spec::EthSpec, ChainSpec};
 
+#[cfg(all(feature = "withdrawals", feature = "withdrawals-processing"))]
 pub fn process_partial_withdrawals<T: EthSpec>(
     state: &mut BeaconState<T>,
     spec: &ChainSpec,

consensus/state_processing/src/upgrade/capella.rs

@@ -57,8 +57,11 @@ pub fn upgrade_to_capella<E: EthSpec>(
         // Execution
         latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_capella(),
         // Withdrawals
+        #[cfg(feature = "withdrawals")]
         withdrawal_queue: VariableList::empty(),
+        #[cfg(feature = "withdrawals")]
         next_withdrawal_index: 0,
+        #[cfg(feature = "withdrawals")]
         next_partial_withdrawal_validator_index: 0,
         // Caches
         total_active_balance: pre.total_active_balance,

consensus/state_processing/src/upgrade/eip4844.rs

@@ -9,6 +9,14 @@ pub fn upgrade_to_eip4844<E: EthSpec>(
     let epoch = pre_state.current_epoch();
     let pre = pre_state.as_capella_mut()?;
 
+    // FIXME(sean) This is a hack to let us participate in testnets where capella doesn't exist.
+    // if we are disabling withdrawals, assume we should fork off of bellatrix.
+    let previous_fork_version = if cfg!(feature ="withdrawals") {
+        pre.fork.current_version
+    } else {
+        spec.bellatrix_fork_epoch
+    };
+
     // Where possible, use something like `mem::take` to move fields from behind the &mut
     // reference. For other fields that don't have a good default value, use `clone`.
     //
@@ -20,7 +28,7 @@ pub fn upgrade_to_eip4844<E: EthSpec>(
         genesis_validators_root: pre.genesis_validators_root,
         slot: pre.slot,
         fork: Fork {
-            previous_version: pre.fork.current_version,
+            previous_version: previous_fork_version,
             current_version: spec.eip4844_fork_version,
             epoch,
         },
@@ -56,8 +64,11 @@ pub fn upgrade_to_eip4844<E: EthSpec>(
         // Execution
         latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_eip4844(),
         // Withdrawals
+        #[cfg(feature = "withdrawals")]
         withdrawal_queue: mem::take(&mut pre.withdrawal_queue),
+        #[cfg(feature = "withdrawals")]
         next_withdrawal_index: pre.next_withdrawal_index,
+        #[cfg(feature = "withdrawals")]
         next_partial_withdrawal_validator_index: pre.next_partial_withdrawal_validator_index,
         // Caches
         total_active_balance: pre.total_active_balance,