Merge rust-bitcoin/rust-miniscript#671: CI: Lint the crate and examples

a410c06b3f1a452f4fa1095558d8f0618ca371af CI: Lint the crate (Tobin C. Harding)
597db61a1cd9fb8bdf96b94177d8d9d5f468e8a2 Remove explicit lifetime (Tobin C. Harding)
362328162919e91049458613e5eefc1a528eda5a Remove unnecessary reference (Tobin C. Harding)

Pull request description:

  We are not currently running the linter in CI, do so.

ACKs for top commit:
  apoelstra:
    ACK a410c06b3f1a452f4fa1095558d8f0618ca371af

Tree-SHA512: 7173394e5fa857e557093ce1ddf4f06d9143c2c37f484800b55f31c6ebef49fad884b277d642426fc0ef0bf5c8971859655fb1607a5c6953d0deb0fd1c094d63

Author: heap-coder

.github/workflows/rust.yml

@@ -15,6 +15,8 @@ jobs:
           profile: minimal
           toolchain: nightly
           override: true
+      - name: Install clippy
+        run: rustup component add clippy
       - name: Running benchmarks
         env:
           DO_BENCH: true
@@ -27,6 +29,10 @@ jobs:
         env:
           DO_FMT: true
         run: ./contrib/test.sh
+      - name: Running linter
+        env:
+          DO_LINT: true
+        run: ./contrib/test.sh
 
   Int-tests:
     name: Integration tests

contrib/test.sh

@@ -33,6 +33,14 @@ fi
 # Defaults / sanity checks
 cargo test
 
+if [ "$DO_LINT" = true ]; then
+    clippy="cargo +nightly clippy"
+
+    $clippy --all-features --all-targets -- -D warnings
+    $clippy --all-targets -- -D warnings
+    $clippy --no-default-features --features=no-std --all-targets -- -D warnings
+fi
+
 if [ "$DO_FEATURE_MATRIX" = true ]
 then
     # All features

src/lib.rs

@@ -754,7 +754,7 @@ mod prelude {
         impl<T: ?Sized> Deref for MutexGuard<'_, T> {
             type Target = T;
 
-            fn deref(&self) -> &T { &self.lock.deref() }
+            fn deref(&self) -> &T { self.lock.deref() }
         }
 
         impl<T: ?Sized> DerefMut for MutexGuard<'_, T> {
@@ -764,7 +764,7 @@ mod prelude {
         impl<T> Mutex<T> {
             pub fn new(inner: T) -> Mutex<T> { Mutex { inner: RefCell::new(inner) } }
 
-            pub fn lock<'a>(&'a self) -> LockResult<MutexGuard<'a, T>> {
+            pub fn lock(&self) -> LockResult<MutexGuard<'_, T>> {
                 Ok(MutexGuard { lock: self.inner.borrow_mut() })
             }
         }