Fix various clippy lints

validator_client/src/duties/epoch_duties.rs

@@ -47,7 +47,7 @@ impl EpochDutiesMap {
     pub fn get(&self, epoch: Epoch) -> Result<Option<EpochDuties>, EpochDutiesMapError> {
         let map = self.map.read().map_err(|_| EpochDutiesMapError::Poisoned)?;
         match map.get(&epoch) {
-            Some(duties) => Ok(Some(duties.clone())),
+            Some(duties) => Ok(Some(*duties)),
             None => Ok(None),
         }
     }

validator_client/src/duties/mod.rs

@@ -12,7 +12,7 @@ use self::traits::{BeaconNode, BeaconNodeError};
 use bls::PublicKey;
 use slot_clock::SlotClock;
 use std::sync::Arc;
-use types::{ChainSpec, Epoch, Slot};
+use types::{ChainSpec, Epoch};
 
 #[derive(Debug, PartialEq, Clone, Copy)]
 pub enum PollOutcome {
@@ -33,7 +33,6 @@ pub enum Error {
     SlotClockError,
     SlotUnknowable,
     EpochMapPoisoned,
-    EpochLengthIsZero,
     BeaconNodeError(BeaconNodeError),
 }
 
@@ -103,6 +102,7 @@ mod tests {
     use super::*;
     use bls::Keypair;
     use slot_clock::TestingSlotClock;
+    use types::Slot;
 
     // TODO: implement more thorough testing.
     // https://github.com/sigp/lighthouse/issues/160