Restore the ability to use Clippy and fix +-50 lints

tools/helios-build/Cargo.toml

@@ -7,7 +7,7 @@ license = "MPL-2.0"
 # Report a specific error in the case that the toolchain is too old for
 # let-else:
 #
-rust-version = "1.65.0"
+rust-version = "1.70.0"
 
 [dependencies]
 anyhow = "1"

tools/helios-build/src/ensure.rs

@@ -340,7 +340,7 @@ pub fn file_str<P: AsRef<Path>>(
         let mut f = std::fs::OpenOptions::new()
             .create_new(true)
             .write(true)
-            .open(&dst)?;
+            .open(dst)?;
         f.write_all(contents.as_bytes())?;
         f.flush()?;
     }
@@ -518,10 +518,7 @@ where
     T: Read + Send + 'static,
 {
     let name = name.to_string();
-    let stream = match stream {
-        Some(stream) => stream,
-        None => return None,
-    };
+    let stream = stream?;
 
     let log = log.clone();
 
@@ -648,7 +645,7 @@ pub fn run_in<S: AsRef<OsStr>, P: AsRef<Path>>(
 ) -> Result<()> {
     let args: Vec<&OsStr> = args.iter().map(|s| s.as_ref()).collect();
 
-    let mut cmd = Command::new(&args[0]);
+    let mut cmd = Command::new(args[0]);
     cmd.current_dir(pwd.as_ref());
 
     scrub_env(&mut cmd, false);
@@ -663,7 +660,7 @@ pub fn run_in<S: AsRef<OsStr>, P: AsRef<Path>>(
 pub fn run<S: AsRef<OsStr>>(log: &Logger, args: &[S]) -> Result<()> {
     let args: Vec<&OsStr> = args.iter().map(|s| s.as_ref()).collect();
 
-    let mut cmd = Command::new(&args[0]);
+    let mut cmd = Command::new(args[0]);
 
     scrub_env(&mut cmd, false);
 
@@ -677,7 +674,7 @@ pub fn run<S: AsRef<OsStr>>(log: &Logger, args: &[S]) -> Result<()> {
 pub fn run_utf8<S: AsRef<OsStr>>(log: &Logger, args: &[S]) -> Result<()> {
     let args: Vec<&OsStr> = args.iter().map(|s| s.as_ref()).collect();
 
-    let mut cmd = Command::new(&args[0]);
+    let mut cmd = Command::new(args[0]);
 
     scrub_env(&mut cmd, true);
 
@@ -697,7 +694,7 @@ where
 {
     let args: Vec<&OsStr> = args.iter().map(|s| s.as_ref()).collect();
 
-    let mut cmd = Command::new(&args[0]);
+    let mut cmd = Command::new(args[0]);
 
     cmd.env_clear();
     cmd.envs(env);

tools/helios-build/src/illumos.rs

@@ -128,7 +128,7 @@ pub fn zonename() -> String {
         let mut buf: [u8; 64] = std::mem::zeroed(); /* ZONENAME_MAX */
 
         let sz = getzonenamebyid(getzoneid(), buf.as_mut_ptr(), 64);
-        if sz > 64 || sz < 0 {
+        if !(0..=64).contains(&sz) {
             eprintln!("getzonenamebyid failure");
             exit(100);
         }
@@ -425,7 +425,8 @@ pub fn zone_list() -> Result<Vec<Zone>> {
 
         let id = if line[0] == "-" { None } else { Some(line[0].parse()?) };
 
-        let uuid = if line[4] == "" { None } else { Some(line[4].to_string()) };
+        let uuid =
+            if line[4].is_empty() { None } else { Some(line[4].to_string()) };
 
         zones.push(Zone {
             id,
@@ -489,8 +490,8 @@ where
     script += "add fs; ";
     script += &format!("set dir = {}; ", ngz.to_str().unwrap());
     script += &format!("set special = {}; ", gz.to_str().unwrap());
-    script += &format!("set type = lofs; ");
-    script += &format!("set options = [rw,nodevices]; ");
+    script += "set type = lofs; ";
+    script += "set options = [rw,nodevices]; ";
     script += "end; ";
     script += "commit; ";
 
@@ -807,7 +808,7 @@ where
         .arg(n)
         .arg("tee")
         .arg("-a")
-        .arg(&p)
+        .arg(p)
         .stdin(std::process::Stdio::piped())
         .spawn()?;
 
@@ -846,7 +847,7 @@ where
         .arg(n)
         .arg("mkdir")
         .arg("-p")
-        .arg(&p)
+        .arg(p)
         .output()?;
 
     if !out.status.success() {
@@ -859,8 +860,8 @@ where
         .arg("-S")
         .arg(n)
         .arg("chown")
-        .arg(&format!("{}:{}", uid, gid))
-        .arg(&p)
+        .arg(format!("{}:{}", uid, gid))
+        .arg(p)
         .output()?;
 
     if !out.status.success() {