Fix clippy suggestions

src/command.rs

@@ -179,7 +179,7 @@ impl<'a> Commands<'a> {
             'outer: loop {
                 let name = command_names
                     .get(i)
-                    .or_else(|| command_names.get(0))
+                    .or_else(|| command_names.first())
                     .copied();
                 i += 1;
 
@@ -271,7 +271,7 @@ impl<'a> Commands<'a> {
             for cmd in &command_strings {
                 let name = command_names
                     .get(i)
-                    .or_else(|| command_names.get(0))
+                    .or_else(|| command_names.first())
                     .copied();
                 commands.push(Command::new_parametrized(
                     name,

src/export/json.rs

@@ -18,7 +18,7 @@ pub struct JsonExporter {}
 impl Exporter for JsonExporter {
     fn serialize(&self, results: &[BenchmarkResult], _unit: Option<Unit>) -> Result<Vec<u8>> {
         let mut output = to_vec_pretty(&HyperfineSummary { results });
-        for content in output.iter_mut() {
+        if let Ok(ref mut content) = output {
             content.push(b'\n');
         }
 

src/options.rs

@@ -67,7 +67,7 @@ impl Shell {
 }
 
 /// Action to take when an executed command fails.
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum CmdFailureAction {
     /// Exit with an error message
     RaiseError,
@@ -77,7 +77,7 @@ pub enum CmdFailureAction {
 }
 
 /// Output style type option
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum OutputStyleOption {
     /// Do not output with colors or any special formatting
     Basic,
@@ -111,7 +111,7 @@ impl Default for RunBounds {
 }
 
 /// How to handle the output of benchmarked commands
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub enum CommandOutputPolicy {
     /// Redirect output to the null device
     Null,

src/parameter/mod.rs

@@ -9,7 +9,7 @@ pub enum ParameterValue {
     Numeric(Number),
 }
 
-impl<'a> ToString for ParameterValue {
+impl ToString for ParameterValue {
     fn to_string(&self) -> String {
         match self {
             ParameterValue::Text(ref value) => value.clone(),

src/util/units.rs

@@ -6,7 +6,7 @@ pub type Scalar = f64;
 pub type Second = Scalar;
 
 /// Supported time units
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Unit {
     Second,
     MilliSecond,