lint: fix a few Clippy errors

PR #3151

crates/cli/src/decompress.rs

@@ -177,7 +177,7 @@ impl DecompressionMatcher {
     /// If there are multiple possible commands matching the given path, then
     /// the command added last takes precedence.
     pub fn command<P: AsRef<Path>>(&self, path: P) -> Option<Command> {
-        for i in self.globs.matches(path).into_iter().rev() {
+        if let Some(i) = self.globs.matches(path).into_iter().next_back() {
             let decomp_cmd = &self.commands[i];
             let mut cmd = Command::new(&decomp_cmd.bin);
             cmd.args(&decomp_cmd.args);

crates/ignore/examples/walk.rs

@@ -18,8 +18,8 @@ fn main() {
     let stdout_thread = std::thread::spawn(move || {
         let mut stdout = std::io::BufWriter::new(std::io::stdout());
         for dent in rx {
-            stdout.write(&*Vec::from_path_lossy(dent.path())).unwrap();
-            stdout.write(b"\n").unwrap();
+            stdout.write_all(&Vec::from_path_lossy(dent.path())).unwrap();
+            stdout.write_all(b"\n").unwrap();
         }
     });
 

crates/printer/src/json.rs

@@ -571,7 +571,7 @@ impl<W: io::Write> JSON<W> {
         } else {
             json::to_writer(&mut self.wtr, message)?;
         }
-        self.wtr.write(&[b'\n'])?;
+        let _ = self.wtr.write(b"\n")?; // This will always be Ok(1) when successful.
         Ok(())
     }
 }

crates/printer/src/jsont.rs

@@ -190,7 +190,7 @@ impl<'a> Data<'a> {
     }
 
     #[cfg(not(unix))]
-    fn from_path(path: &Path) -> Data {
+    fn from_path(path: &Path) -> Data<'_> {
         // Using lossy conversion means some paths won't round trip precisely,
         // but it's not clear what we should actually do. Serde rejects
         // non-UTF-8 paths, and OsStr's are serialized as a sequence of UTF-16