Update for clippy 1.50 (#2193)

## Issue Addressed

NA

## Proposed Changes

Rust 1.50 has landed 🎉

The shiny new `clippy` peers down upon us mere mortals with disgust. Brutish peasants wrapping our `usize`s in superfluous `Option`s... tsk tsk.

I've performed the goat sacrifice and corrected our evil ways in this PR. Tonight we shall pray that Github Actions bestows the almighty green tick upon us.

## Additional Info

NA


Co-authored-by: realbigsean <seananderson33@gmail.com>
Co-authored-by: Michael Sproul <michael@sigmaprime.io>

beacon_node/eth2_libp2p/src/behaviour/mod.rs

@@ -893,7 +893,7 @@ impl<TSpec: EthSpec> Behaviour<TSpec> {
         }
 
         // perform gossipsub score updates when necessary
-        while let Poll::Ready(_) = self.update_gossipsub_scores.poll_tick(cx) {
+        while self.update_gossipsub_scores.poll_tick(cx).is_ready() {
             self.peer_manager.update_gossipsub_scores(&self.gossipsub);
         }
 

beacon_node/eth2_libp2p/src/discovery/enr_ext.rs

@@ -29,7 +29,7 @@ pub trait EnrExt {
 /// Extend ENR CombinedPublicKey for libp2p types.
 pub trait CombinedKeyPublicExt {
     /// Converts the publickey into a peer id, without consuming the key.
-    fn into_peer_id(&self) -> PeerId;
+    fn as_peer_id(&self) -> PeerId;
 }
 
 /// Extend ENR CombinedKey for conversion to libp2p keys.
@@ -41,7 +41,7 @@ pub trait CombinedKeyExt {
 impl EnrExt for Enr {
     /// The libp2p `PeerId` for the record.
     fn peer_id(&self) -> PeerId {
-        self.public_key().into_peer_id()
+        self.public_key().as_peer_id()
     }
 
     /// Returns a list of multiaddrs if the ENR has an `ip` and either a `tcp` or `udp` key **or** an `ip6` and either a `tcp6` or `udp6`.
@@ -195,7 +195,7 @@ impl CombinedKeyPublicExt for CombinedPublicKey {
     /// Converts the publickey into a peer id, without consuming the key.
     ///
     /// This is only available with the `libp2p` feature flag.
-    fn into_peer_id(&self) -> PeerId {
+    fn as_peer_id(&self) -> PeerId {
         match self {
             Self::Secp256k1(pk) => {
                 let pk_bytes = pk.to_bytes();

beacon_node/eth2_libp2p/src/peer_manager/mod.rs

@@ -972,7 +972,7 @@ impl<TSpec: EthSpec> Stream for PeerManager<TSpec> {
 
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         // perform the heartbeat when necessary
-        while let Poll::Ready(_) = self.heartbeat.poll_tick(cx) {
+        while self.heartbeat.poll_tick(cx).is_ready() {
             self.heartbeat();
         }
 

beacon_node/eth2_libp2p/src/rpc/rate_limiter.rs

@@ -240,7 +240,7 @@ impl Future for RPCRateLimiter {
     type Output = ();
 
     fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
-        while let Poll::Ready(_) = self.prune_interval.poll_tick(cx) {
+        while self.prune_interval.poll_tick(cx).is_ready() {
             self.prune();
         }
 

beacon_node/network/src/attestation_service/mod.rs

@@ -584,13 +584,13 @@ impl<T: BeaconChainTypes> AttestationService<T> {
     /// We don't keep track of a specific validator to random subnet, rather the ratio of active
     /// validators to random subnets. So when a validator goes offline, we can simply remove the
     /// allocated amount of random subnets.
-    fn handle_known_validator_expiry(&mut self) -> Result<(), ()> {
+    fn handle_known_validator_expiry(&mut self) {
         let spec = &self.beacon_chain.spec;
         let subnet_count = spec.attestation_subnet_count;
         let random_subnets_per_validator = spec.random_subnets_per_validator;
         if self.known_validators.len() as u64 * random_subnets_per_validator >= subnet_count {
             // have too many validators, ignore
-            return Ok(());
+            return;
         }
 
         let subscribed_subnets = self.random_subnets.keys().cloned().collect::<Vec<_>>();
@@ -616,7 +616,6 @@ impl<T: BeaconChainTypes> AttestationService<T> {
                 .push_back(AttServiceMessage::EnrRemove(*subnet_id));
             self.random_subnets.remove(subnet_id);
         }
-        Ok(())
     }
 }
 

beacon_node/network/src/attestation_service/tests/mod.rs

@@ -203,7 +203,11 @@ async fn subscribe_current_slot_wait_for_unsubscribe() {
     let events = get_events(&mut attestation_service, None, 1).await;
     assert_matches!(
         events[..3],
-        [AttServiceMessage::DiscoverPeers(_), AttServiceMessage::Subscribe(_any1), AttServiceMessage::EnrAdd(_any3)]
+        [
+            AttServiceMessage::DiscoverPeers(_),
+            AttServiceMessage::Subscribe(_any1),
+            AttServiceMessage::EnrAdd(_any3)
+        ]
     );
 
     // If the long lived and short lived subnets are the same, there should be no more events
@@ -281,7 +285,11 @@ async fn test_same_subnet_unsubscription() {
     let events = get_events(&mut attestation_service, None, 1).await;
     assert_matches!(
         events[..3],
-        [AttServiceMessage::DiscoverPeers(_), AttServiceMessage::Subscribe(_any1), AttServiceMessage::EnrAdd(_any3)]
+        [
+            AttServiceMessage::DiscoverPeers(_),
+            AttServiceMessage::Subscribe(_any1),
+            AttServiceMessage::EnrAdd(_any3)
+        ]
     );
 
     let expected = AttServiceMessage::Subscribe(subnet_id1);

beacon_node/network/src/nat.rs

@@ -52,11 +52,7 @@ pub fn construct_upnp_mappings<T: EthSpec>(
                 // Just use the first IP of the first interface that is not a loopback and not an
                 // ipv6 address.
                 if !interface.is_loopback() {
-                    if let IpAddr::V4(_) = interface.ip() {
-                        Some(interface.ip())
-                    } else {
-                        None
-                    }
+                    interface.ip().is_ipv4().then(|| interface.ip())
                 } else {
                     None
                 }

beacon_node/network/src/service.rs

@@ -219,7 +219,7 @@ impl<T: BeaconChainTypes> NetworkService<T> {
             log: network_log,
         };
 
-        spawn_service(executor, network_service)?;
+        spawn_service(executor, network_service);
 
         Ok((network_globals, network_send))
     }
@@ -228,7 +228,7 @@ impl<T: BeaconChainTypes> NetworkService<T> {
 fn spawn_service<T: BeaconChainTypes>(
     executor: task_executor::TaskExecutor,
     mut service: NetworkService<T>,
-) -> error::Result<()> {
+) {
     let mut exit_rx = executor.exit();
     let mut shutdown_sender = executor.shutdown_sender();
 
@@ -570,8 +570,6 @@ fn spawn_service<T: BeaconChainTypes>(
             metrics::update_bandwidth_metrics(service.libp2p.bandwidth.clone());
         }
     }, "network");
-
-    Ok(())
 }
 
 /// Returns a `Sleep` that triggers shortly after the next change in the beacon chain fork version.