Merge #152: Enable clippy in CI

d31b579 CI: Enable clippy (Tobin C. Harding)
1433fd7 Remove unneeded initial variable declaration (Tobin C. Harding)
d3eab6b Use field init shorthand (Tobin C. Harding)
d995a34 Add clippy config file (Tobin C. Harding)

Pull request description:

  Enable running `clippy` on CI, involves doing:

  - Add config file
  - Clear all `clippy` warnings
  - Add CI job to run `clippy`

ACKs for top commit:
  apoelstra:
    ACK d31b579

Tree-SHA512: e675af732f40a886621cbddda5c3570695fb81043680b3093908bdde71d4bd3947580b519e3c41b3463d30f1c408081b7c561c98f06d513501b1e5d4111b8211

Author: apoelstra

.github/workflows/rust.yml

@@ -34,6 +34,22 @@ jobs:
           DO_DOCS: true
         run: ./contrib/test.sh
 
+  Clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+      - run: rustup component add clippy
+      - uses: actions-rs/cargo@v1
+        with:
+          command: clippy
+          args: --all-features -- -D warnings
+
   wasm:
     name: Stable - WebAssembly Build
     runs-on: ubuntu-latest

clippy.toml

@@ -0,0 +1 @@
+msrv = "1.41.1"

src/hex.rs

@@ -84,12 +84,11 @@ impl<T: Hash> FromHex for T {
     where
         I: Iterator<Item = Result<u8, Error>> + ExactSizeIterator + DoubleEndedIterator,
     {
-        let inner;
-        if Self::DISPLAY_BACKWARD {
-            inner = T::Inner::from_byte_iter(iter.rev())?;
+        let inner = if Self::DISPLAY_BACKWARD {
+            T::Inner::from_byte_iter(iter.rev())?
         } else {
-            inner = T::Inner::from_byte_iter(iter)?;
-        }
+            T::Inner::from_byte_iter(iter)?
+        };
         Ok(Hash::from_inner(inner))
     }
 }

src/hmac.rs

@@ -104,8 +104,8 @@ impl<T: Hash> HmacEngine<T> {
     /// A special constructor giving direct access to the underlying "inner" and "outer" engines.
     pub fn from_inner_engines(iengine: T::Engine, oengine: T::Engine) -> HmacEngine<T> {
         HmacEngine {
-            iengine: iengine,
-            oengine: oengine,
+            iengine,
+            oengine,
         }
     }
 }

src/sha256.rs

@@ -269,7 +269,7 @@ impl HashEngine {
         HashEngine {
             buffer: [0; BLOCK_SIZE],
             h: ret,
-            length: length,
+            length,
         }
     }
 

src/siphash24.rs

@@ -94,8 +94,8 @@ impl HashEngine {
     /// Creates a new SipHash24 engine with keys.
     pub fn with_keys(k0: u64, k1: u64) -> HashEngine {
         HashEngine {
-            k0: k0,
-            k1: k1,
+            k0,
+            k1,
             length: 0,
             state: State {
                 v0: k0 ^ 0x736f6d6570736575,