Use the newly available stable clippy. Fix lints.

.travis.yml

@@ -10,17 +10,17 @@ rust:
 
 matrix:
   include:
-  # This build uses stable and checks rustfmt (clippy is not on stable).
+  # This build uses stable and checks rustfmt and clippy.
+  # We don't check them on nightly since their lints and formatting may differ.
   - rust: stable
     install:
       - rustup component add rustfmt-preview
+      - rustup component add clippy-preview
     before_script:
       - cargo fmt --all -- --check
-  - rust: nightly
-    install:
-      - rustup component add clippy-preview --toolchain nightly
-    before_script:
       - cargo clippy --all -- -D clippy::all
+  # Since many users will use nightlies, also test that.
+  - rust: nightly
 
 
 script:

README.md

@@ -36,17 +36,15 @@ A complete Raft model contains 4 essential parts:
 Using `rustup` you can get started this way:
 
 ```bash
-rustup override set stable
-rustup toolchain install nightly
-rustup component add clippy-review --nightly
+rustup component add clippy-preview
 rustup component add rustfmt-preview
 ```
 
 In order to have your PR merged running the following must finish without error:
 
 ```bash
 cargo test --all && \
-cargo +nightly clippy --all && \
+cargo clippy --all -- -D clippy && \
 cargo fmt --all -- --check
 ```
 

benches/benches.rs

@@ -1,4 +1,5 @@
 #![allow(dead_code)] // Due to criterion we need this to avoid warnings.
+#![cfg_attr(feature = "cargo-clippy", allow(let_and_return))] // Benches often artificially return values. Allow it.
 
 extern crate criterion;
 extern crate env_logger;

benches/suites/progress.rs

@@ -8,7 +8,7 @@ pub fn bench_progress(c: &mut Criterion) {
 pub fn bench_progress_default(c: &mut Criterion) {
     let bench = |b: &mut Bencher| {
         // No setup.
-        b.iter(|| Progress::default());
+        b.iter(Progress::default);
     };
 
     c.bench_function("Progress::default", bench);

benches/suites/raft.rs

@@ -59,7 +59,7 @@ pub fn bench_raft_campaign(c: &mut Criterion) {
                 "CampaignTransfer",
             ];
             // Skip the first since it's 0,0
-            for msg in msgs.iter() {
+            for msg in &msgs {
                 c.bench_function(
                     &format!("Raft::campaign ({}, {}, {})", voters, learners, msg),
                     bench(*voters, *learners, msg.as_bytes()),

benches/suites/raw_node.rs

@@ -17,7 +17,7 @@ fn quick_raw_node() -> RawNode<MemStorage> {
 pub fn bench_raw_node_new(c: &mut Criterion) {
     let bench = |b: &mut Bencher| {
         // No setup.
-        b.iter(|| quick_raw_node());
+        b.iter(quick_raw_node);
     };
 
     c.bench_function("RawNode::new", bench);

rust-toolchain

@@ -0,0 +1 @@
+stable

src/eraftpb.rs

@@ -3,7 +3,7 @@
 
 // https://github.com/Manishearth/rust-clippy/issues/702
 #![allow(unknown_lints)]
-#![cfg_attr(feature = "cargo-clippy", allow(clippy::all))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy))]
 
 #![cfg_attr(rustfmt, rustfmt_skip)]
 

src/errors.rs

@@ -67,7 +67,7 @@ quick_error! {
 }
 
 impl cmp::PartialEq for Error {
-    #[cfg_attr(feature = "cargo-clippy", allow(clippy::match_same_arms))]
+    #[cfg_attr(feature = "cargo-clippy", allow(match_same_arms))]
     fn eq(&self, other: &Error) -> bool {
         match (self, other) {
             (&Error::StepPeerNotFound, &Error::StepPeerNotFound) => true,
@@ -112,7 +112,7 @@ quick_error! {
 }
 
 impl cmp::PartialEq for StorageError {
-    #[cfg_attr(feature = "cargo-clippy", allow(clippy::match_same_arms))]
+    #[cfg_attr(feature = "cargo-clippy", allow(match_same_arms))]
     fn eq(&self, other: &StorageError) -> bool {
         match (self, other) {
             (&StorageError::Compacted, &StorageError::Compacted) => true,

src/lib.rs

@@ -261,7 +261,6 @@ For more information, check out an [example](examples/single_mem_node/main.rs#L1
 */
 
 #![cfg_attr(not(feature = "cargo-clippy"), allow(unknown_lints))]
-#![cfg_attr(feature = "cargo-clippy", feature(tool_lints))]
 #![deny(missing_docs)]
 
 #[cfg(feature = "failpoint")]

src/progress.rs

@@ -452,7 +452,7 @@ mod test {
             buffer: Vec::with_capacity(10),
             ..Default::default()
         };
-        inflight2.buffer.extend_from_slice(&vec![0, 0, 0, 0, 0]);
+        inflight2.buffer.extend_from_slice(&[0, 0, 0, 0, 0]);
 
         for i in 0..5 {
             inflight2.add(i);

src/raft.rs

@@ -572,10 +572,7 @@ impl<T: Storage> Raft<T> {
         self.bcast_heartbeat_with_ctx(ctx)
     }
 
-    #[cfg_attr(
-        feature = "cargo-clippy",
-        allow(clippy::needless_pass_by_value)
-    )]
+    #[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
     fn bcast_heartbeat_with_ctx(&mut self, ctx: Option<Vec<u8>>) {
         let self_id = self.id;
         let mut prs = self.take_prs();

src/raft_log.rs

@@ -955,7 +955,7 @@ mod test {
         let (offset, num) = (100u64, 100u64);
         let (last, half) = (offset + num, offset + num / 2);
         let halfe = new_entry(half, half);
-        let halfe_size = protobuf::Message::compute_size(&halfe) as u64;
+        let halfe_size = u64::from(protobuf::Message::compute_size(&halfe));
 
         let store = MemStorage::new();
         store

src/raw_node.rs

@@ -286,10 +286,7 @@ impl<T: Storage> RawNode<T> {
     }
 
     /// ProposeConfChange proposes a config change.
-    #[cfg_attr(
-        feature = "cargo-clippy",
-        allow(clippy::needless_pass_by_value)
-    )]
+    #[cfg_attr(feature = "cargo-clippy", allow(needless_pass_by_value))]
     pub fn propose_conf_change(&mut self, context: Vec<u8>, cc: ConfChange) -> Result<()> {
         let data = protobuf::Message::write_to_bytes(&cc)?;
         let mut m = Message::new();

src/storage.rs

@@ -409,26 +409,26 @@ mod test {
             (
                 4,
                 7,
-                (size_of(&ents[1]) + size_of(&ents[2])) as u64,
+                u64::from(size_of(&ents[1]) + size_of(&ents[2])),
                 Ok(vec![new_entry(4, 4), new_entry(5, 5)]),
             ),
             (
                 4,
                 7,
-                (size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3]) / 2) as u64,
+                u64::from(size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3]) / 2),
                 Ok(vec![new_entry(4, 4), new_entry(5, 5)]),
             ),
             (
                 4,
                 7,
-                (size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3]) - 1) as u64,
+                u64::from(size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3]) - 1),
                 Ok(vec![new_entry(4, 4), new_entry(5, 5)]),
             ),
             // all
             (
                 4,
                 7,
-                (size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3])) as u64,
+                u64::from(size_of(&ents[1]) + size_of(&ents[2]) + size_of(&ents[3])),
                 Ok(vec![new_entry(4, 4), new_entry(5, 5), new_entry(6, 6)]),
             ),
         ];

tests/integration_cases/test_raft.rs

@@ -45,10 +45,10 @@ fn new_progress(
     ins_size: usize,
 ) -> Progress {
     Progress {
-        state: state,
-        matched: matched,
-        next_idx: next_idx,
-        pending_snapshot: pending_snapshot,
+        state,
+        matched,
+        next_idx,
+        pending_snapshot,
         ins: Inflights::new(ins_size),
         ..Default::default()
     }
@@ -110,12 +110,12 @@ fn new_raft_log(ents: &[Entry], offset: u64, committed: u64) -> RaftLog<MemStora
     let store = MemStorage::new();
     store.wl().append(ents).expect("");
     RaftLog {
-        store: store,
+        store,
         unstable: Unstable {
-            offset: offset,
+            offset,
             ..Default::default()
         },
-        committed: committed,
+        committed,
         ..Default::default()
     }
 }
@@ -263,8 +263,8 @@ fn test_progress_is_paused() {
     ];
     for (i, &(state, paused, w)) in tests.iter().enumerate() {
         let p = Progress {
-            state: state,
-            paused: paused,
+            state,
+            paused,
             ins: Inflights::new(256),
             ..Default::default()
         };
@@ -581,7 +581,7 @@ fn test_vote_from_any_state_for_type(vt: MessageType) {
         msg.set_log_term(new_term);
         msg.set_index(42);
         r.step(msg)
-            .expect(&format!("{:?},{:?}: step failed", vt, state));
+            .unwrap_or_else(|_| panic!("{:?},{:?}: step failed", vt, state));
         assert_eq!(
             r.msgs.len(),
             1,
@@ -1177,7 +1177,7 @@ fn test_pass_election_timeout() {
         if round {
             got = (got * 10.0 + 0.5).floor() / 10.0;
         }
-        if (got - wprobability).abs() > 0.000001 {
+        if (got - wprobability).abs() > 0.000_001 {
             panic!("#{}: probability = {}, want {}", i, got, wprobability);
         }
     }

tests/integration_cases/test_raw_node.rs

@@ -33,7 +33,7 @@ use test_util::*;
 
 fn new_peer(id: u64) -> Peer {
     Peer {
-        id: id,
+        id,
         ..Default::default()
     }
 }
@@ -64,11 +64,11 @@ fn new_ready(
     must_sync: bool,
 ) -> Ready {
     Ready {
-        ss: ss,
-        hs: hs,
-        entries: entries,
+        ss,
+        hs,
+        entries,
         committed_entries: Some(committed_entries),
-        must_sync: must_sync,
+        must_sync,
         ..Default::default()
     }
 }

tests/test_util/mod.rs

@@ -52,12 +52,17 @@ pub fn new_storage() -> MemStorage {
     MemStorage::new()
 }
 
-pub fn new_test_config(id: u64, peers: Vec<u64>, election: usize, heartbeat: usize) -> Config {
+pub fn new_test_config(
+    id: u64,
+    peers: Vec<u64>,
+    election_tick: usize,
+    heartbeat_tick: usize,
+) -> Config {
     Config {
-        id: id,
-        peers: peers,
-        election_tick: election,
-        heartbeat_tick: heartbeat,
+        id,
+        peers,
+        election_tick,
+        heartbeat_tick,
         max_size_per_msg: NO_LIMIT,
         max_inflight_msgs: 256,
         ..Default::default()
@@ -224,6 +229,7 @@ struct Connem {
     to: u64,
 }
 
+#[allow(declare_interior_mutable_const)]
 pub const NOP_STEPPER: Option<Interface> = Some(Interface { raft: None });
 
 #[derive(Default)]
@@ -322,7 +328,7 @@ impl Network {
     }
 
     pub fn drop(&mut self, from: u64, to: u64, perc: f64) {
-        self.dropm.insert(Connem { from: from, to: to }, perc);
+        self.dropm.insert(Connem { from, to }, perc);
     }
 
     pub fn cut(&mut self, one: u64, other: u64) {

tests/tests.rs

@@ -12,7 +12,6 @@
 // limitations under the License.
 
 #![cfg_attr(not(feature = "cargo-clippy"), allow(unknown_lints))]
-#![cfg_attr(feature = "cargo-clippy", feature(tool_lints))]
 #![cfg_attr(feature = "failpoint", allow(dead_code, unused_imports))]
 
 #[macro_use]