diff --git a/proc_macro/src/bridge/fxhash.rs b/proc_macro/src/bridge/fxhash.rs
index f4e9054419721..f9f74c63fc4f6 100644
--- a/proc_macro/src/bridge/fxhash.rs
+++ b/proc_macro/src/bridge/fxhash.rs
@@ -69,7 +69,7 @@ impl Hasher for FxHasher {
             hash.add_to_hash(u16::from_ne_bytes(bytes[..2].try_into().unwrap()) as usize);
             bytes = &bytes[2..];
         }
-        if (size_of::<usize>() > 1) && bytes.len() >= 1 {
+        if (size_of::<usize>() > 1) && !bytes.is_empty() {
             hash.add_to_hash(bytes[0] as usize);
         }
         self.hash = hash.hash;
diff --git a/proc_macro/src/bridge/rpc.rs b/proc_macro/src/bridge/rpc.rs
index 6d75a5a627c82..202a8e04543b2 100644
--- a/proc_macro/src/bridge/rpc.rs
+++ b/proc_macro/src/bridge/rpc.rs
@@ -264,9 +264,9 @@ impl From<Box<dyn Any + Send>> for PanicMessage {
     }
 }
 
-impl Into<Box<dyn Any + Send>> for PanicMessage {
-    fn into(self) -> Box<dyn Any + Send> {
-        match self {
+impl From<PanicMessage> for Box<dyn Any + Send> {
+    fn from(val: PanicMessage) -> Self {
+        match val {
             PanicMessage::StaticStr(s) => Box::new(s),
             PanicMessage::String(s) => Box::new(s),
             PanicMessage::Unknown => {
diff --git a/test/src/cli.rs b/test/src/cli.rs
index 6ac3b3eaa797b..b7d24405b775e 100644
--- a/test/src/cli.rs
+++ b/test/src/cli.rs
@@ -200,7 +200,7 @@ Test Attributes:
 pub fn parse_opts(args: &[String]) -> Option<OptRes> {
     // Parse matches.
     let opts = optgroups();
-    let binary = args.get(0).map(|c| &**c).unwrap_or("...");
+    let binary = args.first().map(|c| &**c).unwrap_or("...");
     let args = args.get(1..).unwrap_or(args);
     let matches = match opts.parse(args) {
         Ok(m) => m,
diff --git a/test/src/term/terminfo/parm.rs b/test/src/term/terminfo/parm.rs
index 2815f6cfc77fe..c5b4ef01893c2 100644
--- a/test/src/term/terminfo/parm.rs
+++ b/test/src/term/terminfo/parm.rs
@@ -524,7 +524,7 @@ fn format(val: Param, op: FormatOp, flags: Flags) -> Result<Vec<u8>, String> {
         } else {
             let mut s_ = Vec::with_capacity(flags.width);
             s_.extend(repeat(b' ').take(n));
-            s_.extend(s.into_iter());
+            s_.extend(s);
             s = s_;
         }
     }