Apply Clippy lints

.github/workflows/main.yml

@@ -60,6 +60,18 @@ jobs:
         rustup component add rustfmt
     - run: cargo fmt -- --check
 
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+    - name: Install Rust
+      run: |
+        rustup update stable --no-self-update
+        rustup default stable
+        rustup component add clippy
+    - run: cargo clippy --verbose
+
   features:
     name: Feature check
     runs-on: ubuntu-latest

build.rs

@@ -22,7 +22,7 @@ fn main() {
 }
 
 fn target_has_atomic_cas(target: &str) -> bool {
-    match &target[..] {
+    match target {
         "thumbv6m-none-eabi"
         | "msp430-none-elf"
         | "riscv32i-unknown-none-elf"
@@ -32,7 +32,7 @@ fn target_has_atomic_cas(target: &str) -> bool {
 }
 
 fn target_has_atomics(target: &str) -> bool {
-    match &target[..] {
+    match target {
         "thumbv4t-none-eabi"
         | "msp430-none-elf"
         | "riscv32i-unknown-none-elf"

clippy.toml

@@ -0,0 +1 @@
+msrv = "1.31.0"

src/kv/key.rs

@@ -1,9 +1,7 @@
 //! Structured keys.
 
 use std::borrow::Borrow;
-use std::cmp;
 use std::fmt;
-use std::hash;
 
 /// A type that can be converted into a [`Key`](struct.Key.html).
 pub trait ToKey {
@@ -33,15 +31,15 @@ impl ToKey for str {
 }
 
 /// A key in a structured key-value pair.
-#[derive(Clone)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Key<'k> {
     key: &'k str,
 }
 
 impl<'k> Key<'k> {
     /// Get a key from a borrowed string.
     pub fn from_str(key: &'k str) -> Self {
-        Key { key: key }
+        Key { key }
     }
 
     /// Get a borrowed string from this key.
@@ -50,47 +48,12 @@ impl<'k> Key<'k> {
     }
 }
 
-impl<'k> fmt::Debug for Key<'k> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        self.key.fmt(f)
-    }
-}
-
 impl<'k> fmt::Display for Key<'k> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.key.fmt(f)
     }
 }
 
-impl<'k> hash::Hash for Key<'k> {
-    fn hash<H>(&self, state: &mut H)
-    where
-        H: hash::Hasher,
-    {
-        self.as_str().hash(state)
-    }
-}
-
-impl<'k, 'ko> PartialEq<Key<'ko>> for Key<'k> {
-    fn eq(&self, other: &Key<'ko>) -> bool {
-        self.as_str().eq(other.as_str())
-    }
-}
-
-impl<'k> Eq for Key<'k> {}
-
-impl<'k, 'ko> PartialOrd<Key<'ko>> for Key<'k> {
-    fn partial_cmp(&self, other: &Key<'ko>) -> Option<cmp::Ordering> {
-        self.as_str().partial_cmp(other.as_str())
-    }
-}
-
-impl<'k> Ord for Key<'k> {
-    fn cmp(&self, other: &Self) -> cmp::Ordering {
-        self.as_str().cmp(other.as_str())
-    }
-}
-
 impl<'k> AsRef<str> for Key<'k> {
     fn as_ref(&self) -> &str {
         self.as_str()

src/lib.rs

@@ -421,7 +421,7 @@ static LEVEL_PARSE_ERROR: &str =
 /// [`log!`](macro.log.html), and comparing a `Level` directly to a
 /// [`LevelFilter`](enum.LevelFilter.html).
 #[repr(usize)]
-#[derive(Copy, Eq, Debug, Hash)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
 pub enum Level {
     /// The "error" level.
     ///
@@ -448,86 +448,18 @@ pub enum Level {
     Trace,
 }
 
-impl Clone for Level {
-    #[inline]
-    fn clone(&self) -> Level {
-        *self
-    }
-}
-
-impl PartialEq for Level {
-    #[inline]
-    fn eq(&self, other: &Level) -> bool {
-        *self as usize == *other as usize
-    }
-}
-
 impl PartialEq<LevelFilter> for Level {
     #[inline]
     fn eq(&self, other: &LevelFilter) -> bool {
         *self as usize == *other as usize
     }
 }
 
-impl PartialOrd for Level {
-    #[inline]
-    fn partial_cmp(&self, other: &Level) -> Option<cmp::Ordering> {
-        Some(self.cmp(other))
-    }
-
-    #[inline]
-    fn lt(&self, other: &Level) -> bool {
-        (*self as usize) < *other as usize
-    }
-
-    #[inline]
-    fn le(&self, other: &Level) -> bool {
-        *self as usize <= *other as usize
-    }
-
-    #[inline]
-    fn gt(&self, other: &Level) -> bool {
-        *self as usize > *other as usize
-    }
-
-    #[inline]
-    fn ge(&self, other: &Level) -> bool {
-        *self as usize >= *other as usize
-    }
-}
-
 impl PartialOrd<LevelFilter> for Level {
     #[inline]
     fn partial_cmp(&self, other: &LevelFilter) -> Option<cmp::Ordering> {
         Some((*self as usize).cmp(&(*other as usize)))
     }
-
-    #[inline]
-    fn lt(&self, other: &LevelFilter) -> bool {
-        (*self as usize) < *other as usize
-    }
-
-    #[inline]
-    fn le(&self, other: &LevelFilter) -> bool {
-        *self as usize <= *other as usize
-    }
-
-    #[inline]
-    fn gt(&self, other: &LevelFilter) -> bool {
-        *self as usize > *other as usize
-    }
-
-    #[inline]
-    fn ge(&self, other: &LevelFilter) -> bool {
-        *self as usize >= *other as usize
-    }
-}
-
-impl Ord for Level {
-    #[inline]
-    fn cmp(&self, other: &Level) -> cmp::Ordering {
-        (*self as usize).cmp(&(*other as usize))
-    }
 }
 
 fn ok_or<T, E>(t: Option<T>, e: E) -> Result<T, E> {
@@ -637,7 +569,7 @@ impl Level {
 /// [`max_level()`]: fn.max_level.html
 /// [`set_max_level`]: fn.set_max_level.html
 #[repr(usize)]
-#[derive(Copy, Eq, Debug, Hash)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
 pub enum LevelFilter {
     /// A level lower than all log levels.
     Off,
@@ -653,88 +585,18 @@ pub enum LevelFilter {
     Trace,
 }
 
-// Deriving generates terrible impls of these traits
-
-impl Clone for LevelFilter {
-    #[inline]
-    fn clone(&self) -> LevelFilter {
-        *self
-    }
-}
-
-impl PartialEq for LevelFilter {
-    #[inline]
-    fn eq(&self, other: &LevelFilter) -> bool {
-        *self as usize == *other as usize
-    }
-}
-
 impl PartialEq<Level> for LevelFilter {
     #[inline]
     fn eq(&self, other: &Level) -> bool {
         other.eq(self)
     }
 }
 
-impl PartialOrd for LevelFilter {
-    #[inline]
-    fn partial_cmp(&self, other: &LevelFilter) -> Option<cmp::Ordering> {
-        Some(self.cmp(other))
-    }
-
-    #[inline]
-    fn lt(&self, other: &LevelFilter) -> bool {
-        (*self as usize) < *other as usize
-    }
-
-    #[inline]
-    fn le(&self, other: &LevelFilter) -> bool {
-        *self as usize <= *other as usize
-    }
-
-    #[inline]
-    fn gt(&self, other: &LevelFilter) -> bool {
-        *self as usize > *other as usize
-    }
-
-    #[inline]
-    fn ge(&self, other: &LevelFilter) -> bool {
-        *self as usize >= *other as usize
-    }
-}
-
 impl PartialOrd<Level> for LevelFilter {
     #[inline]
     fn partial_cmp(&self, other: &Level) -> Option<cmp::Ordering> {
         Some((*self as usize).cmp(&(*other as usize)))
     }
-
-    #[inline]
-    fn lt(&self, other: &Level) -> bool {
-        (*self as usize) < *other as usize
-    }
-
-    #[inline]
-    fn le(&self, other: &Level) -> bool {
-        *self as usize <= *other as usize
-    }
-
-    #[inline]
-    fn gt(&self, other: &Level) -> bool {
-        *self as usize > *other as usize
-    }
-
-    #[inline]
-    fn ge(&self, other: &Level) -> bool {
-        *self as usize >= *other as usize
-    }
-}
-
-impl Ord for LevelFilter {
-    #[inline]
-    fn cmp(&self, other: &LevelFilter) -> cmp::Ordering {
-        (*self as usize).cmp(&(*other as usize))
-    }
 }
 
 impl FromStr for LevelFilter {
@@ -1142,6 +1004,12 @@ impl<'a> RecordBuilder<'a> {
     }
 }
 
+impl<'a> Default for RecordBuilder<'a> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 /// Metadata about a log message.
 ///
 /// # Use
@@ -1265,6 +1133,12 @@ impl<'a> MetadataBuilder<'a> {
     }
 }
 
+impl<'a> Default for MetadataBuilder<'a> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 /// A trait encapsulating the operations required of a logger.
 pub trait Log: Sync + Send {
     /// Determines if a log message with the specified metadata would be
@@ -1307,10 +1181,10 @@ where
     }
 
     fn log(&self, record: &Record) {
-        (**self).log(record)
+        (**self).log(record);
     }
     fn flush(&self) {
-        (**self).flush()
+        (**self).flush();
     }
 }
 
@@ -1355,7 +1229,7 @@ where
 /// Note that `Trace` is the maximum level, because it provides the maximum amount of detail in the emitted logs.
 #[inline]
 pub fn set_max_level(level: LevelFilter) {
-    MAX_LOG_LEVEL_FILTER.store(level as usize, Ordering::Relaxed)
+    MAX_LOG_LEVEL_FILTER.store(level as usize, Ordering::Relaxed);
 }
 
 /// Returns the current maximum log level.
@@ -1546,7 +1420,7 @@ impl error::Error for SetLoggerError {}
 ///
 /// [`from_str`]: https://doc.rust-lang.org/std/str/trait.FromStr.html#tymethod.from_str
 #[allow(missing_copy_implementations)]
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct ParseLevelError(());
 
 impl fmt::Display for ParseLevelError {

tests/filters.rs

@@ -69,15 +69,15 @@ fn main() {
 fn test(a: &State, filter: LevelFilter) {
     log::set_max_level(filter);
     error!("");
-    last(&a, t(Level::Error, filter));
+    last(a, t(Level::Error, filter));
     warn!("");
-    last(&a, t(Level::Warn, filter));
+    last(a, t(Level::Warn, filter));
     info!("");
-    last(&a, t(Level::Info, filter));
+    last(a, t(Level::Info, filter));
     debug!("");
-    last(&a, t(Level::Debug, filter));
+    last(a, t(Level::Debug, filter));
     trace!("");
-    last(&a, t(Level::Trace, filter));
+    last(a, t(Level::Trace, filter));
 
     fn t(lvl: Level, filter: LevelFilter) -> Option<Level> {
         if lvl <= filter {