Apply clippy suggestions

crates/nu-command/src/experimental/job_wait.rs

@@ -55,20 +55,16 @@ Note that this command fails if the provided job id is currently not in the job
         let mut jobs = engine_state.jobs.lock().expect("jobs lock is poisoned!");
 
         match jobs.lookup_mut(id) {
-            None => {
-                return Err(ShellError::JobNotFound {
-                    id: id.get(),
-                    span: head,
-                });
-            }
+            None => Err(ShellError::JobNotFound {
+                id: id.get(),
+                span: head,
+            }),
 
-            Some(Job::Frozen { .. }) => {
-                return Err(ShellError::UnsupportedJobType {
-                    id: id.get() as usize,
-                    span: head,
-                    kind: "frozen".to_string(),
-                });
-            }
+            Some(Job::Frozen { .. }) => Err(ShellError::UnsupportedJobType {
+                id: id.get() as usize,
+                span: head,
+                kind: "frozen".to_string(),
+            }),
 
             Some(Job::Thread(job)) => {
                 let waiter = job.on_termination().clone();
@@ -104,9 +100,8 @@ pub fn wait_with_interrupt<R, E>(
     loop {
         interrupted()?;
 
-        match wait(check_interval) {
-            Some(result) => return Ok(result),
-            None => {} // do nothing, try again
+        if let Some(result) = wait(check_interval) {
+            return Ok(result);
         }
     }
 }

crates/nu-protocol/src/engine/jobs.rs

@@ -1,7 +1,6 @@
 use std::{
     collections::{HashMap, HashSet},
-    sync::{Arc, Mutex, WaitTimeoutResult},
-    time::Instant,
+    sync::{Arc, Mutex},
 };
 
 use nu_system::{kill_by_pid, UnfreezeHandle};
@@ -336,9 +335,9 @@ impl<T> Waiter<T> {
         {
             Ok((_guard, result)) => {
                 if result.timed_out() {
-                    return None;
+                    None
                 } else {
-                    return Some(inner.value.get().unwrap());
+                    Some(inner.value.get().unwrap())
                 }
             }
             Err(_) => panic!("mutex is poisoned!"),

crates/nu-system/src/util.rs

@@ -1,6 +1,5 @@
 use std::io;
 use std::process::Command as CommandSys;
-use std::time::{Duration, Instant};
 
 /// Tries to forcefully kill a process by its PID
 pub fn kill_by_pid(pid: i64) -> io::Result<()> {