Fix clippy warnings (#1385)

## Issue Addressed

NA

## Proposed Changes

Fixes most clippy warnings and ignores the rest of them, see issue #1388.

validator_client/src/attestation_service.rs

@@ -190,7 +190,7 @@ impl<T: SlotClock + 'static, E: EthSpec> AttestationService<T, E> {
             .into_iter()
             .fold(HashMap::new(), |mut map, duty_and_proof| {
                 if let Some(committee_index) = duty_and_proof.duty.attestation_committee_index {
-                    let validator_duties = map.entry(committee_index).or_insert_with(|| vec![]);
+                    let validator_duties = map.entry(committee_index).or_insert_with(Vec::new);
 
                     validator_duties.push(duty_and_proof);
                 }

validator_client/src/duties_service.rs

@@ -151,9 +151,9 @@ enum InsertOutcome {
 
 impl InsertOutcome {
     /// Returns `true` if the outcome indicates that the validator _might_ require a subscription.
-    pub fn is_subscription_candidate(self) -> bool {
+    pub fn is_subscription_candidate(&self) -> bool {
         match self {
-            InsertOutcome::Replaced { should_resubscribe } => should_resubscribe,
+            InsertOutcome::Replaced { should_resubscribe } => *should_resubscribe,
             InsertOutcome::NewValidator | InsertOutcome::NewEpoch => true,
             InsertOutcome::Identical | InsertOutcome::Invalid | InsertOutcome::NewProposalSlots => {
                 false

validator_client/src/fork_service.rs

@@ -95,7 +95,7 @@ impl<T, E: EthSpec> Deref for ForkService<T, E> {
 impl<T: SlotClock + 'static, E: EthSpec> ForkService<T, E> {
     /// Returns the last fork downloaded from the beacon node, if any.
     pub fn fork(&self) -> Option<Fork> {
-        self.fork.read().clone()
+        *self.fork.read()
     }
 
     /// Starts the service that periodically polls for the `Fork`.

validator_client/src/initialized_validators.rs

@@ -345,11 +345,14 @@ impl InitializedValidators {
         voting_public_key: &PublicKey,
         enabled: bool,
     ) -> Result<(), Error> {
-        self.definitions
+        if let Some(def) = self
+            .definitions
             .as_mut_slice()
             .iter_mut()
             .find(|def| def.voting_public_key == *voting_public_key)
-            .map(|def| def.enabled = enabled);
+        {
+            def.enabled = enabled;
+        }
 
         self.update_validators()?;
 

validator_client/src/validator_definitions.rs

@@ -6,7 +6,6 @@
 use account_utils::{create_with_600_perms, default_keystore_password_path, ZeroizeString};
 use eth2_keystore::Keystore;
 use serde_derive::{Deserialize, Serialize};
-use serde_yaml;
 use slog::{error, Logger};
 use std::collections::HashSet;
 use std::fs::{self, OpenOptions};
@@ -230,14 +229,13 @@ pub fn recursively_find_voting_keystores<P: AsRef<Path>>(
         let file_type = dir_entry.file_type()?;
         if file_type.is_dir() {
             recursively_find_voting_keystores(dir_entry.path(), matches)?
-        } else if file_type.is_file() {
-            if dir_entry
+        } else if file_type.is_file()
+            && dir_entry
                 .file_name()
                 .to_str()
                 .map_or(false, |filename| filename == VOTING_KEYSTORE_FILE)
-            {
-                matches.push(dir_entry.path())
-            }
+        {
+            matches.push(dir_entry.path())
         }
         Ok(())
     })