add consolidation processing

consensus/types/src/beacon_state.rs

@@ -160,6 +160,7 @@ pub enum Error {
     InvalidFlagIndex(usize),
     MerkleTreeError(merkle_proof::MerkleTreeError),
     PartialWithdrawalCountInvalid(usize),
+    NonExecutionAddresWithdrawalCredential,
 }
 
 /// Control whether an epoch-indexed field can be indexed at the next epoch or not.

consensus/types/src/consolidation.rs

@@ -1,5 +1,5 @@
-use crate::test_utils::TestRandom;
 use crate::Epoch;
+use crate::{test_utils::TestRandom, SignedRoot};
 use serde::{Deserialize, Serialize};
 use ssz_derive::{Decode, Encode};
 use test_random_derive::TestRandom;
@@ -27,6 +27,8 @@ pub struct Consolidation {
     pub epoch: Epoch,
 }
 
+impl SignedRoot for Consolidation {}
+
 #[cfg(test)]
 mod tests {
     use super::*;

consensus/types/src/validator.rs

@@ -142,6 +142,18 @@ impl Validator {
             .flatten()
     }
 
+    /// Get the execution withdrawal address if this validator has one initialized.
+    pub fn get_execution_withdrawal_address(&self, spec: &ChainSpec) -> Option<Address> {
+        self.has_execution_withdrawal_credential(spec)
+            .then(|| {
+                self.withdrawal_credentials
+                    .as_bytes()
+                    .get(12..)
+                    .map(Address::from_slice)
+            })
+            .flatten()
+    }
+
     /// Changes withdrawal credentials to  the provided eth1 execution address.
     ///
     /// WARNING: this function does NO VALIDATION - it just does it!