2 files changed, 21 insertions, 24 deletions

diff --git a/src/run/builtin.rs b/src/run/builtin.rs
index 24badd0..99e0103 100644
--- a/src/run/builtin.rs
+++ b/src/run/builtin.rs
@@ -34,13 +34,13 @@ fn read_args<T: ArgParse>(args: &[BString], w: &mut dyn Write) -> std::result::R
             w.write_all(b"\n")?;
         }
         ArgParseError::MissingArg(arg) => {
-            write!(w, "argument `{arg}` is missing\n")?;
+            writeln!(w, "argument `{arg}` is missing")?;
         }
         ArgParseError::MissingArgValue(arg) => {
-            write!(w, "argument `{arg}` is missing its value\n")?;
+            writeln!(w, "argument `{arg}` is missing its value")?;
         }
         ArgParseError::ArgValueParseError(arg, err) => {
-            write!(w, "failed to parse value of `{arg}`: {err}")?;
+            writeln!(w, "failed to parse value of `{arg}`: {err}")?;
         }
     }
 
@@ -66,7 +66,7 @@ impl Builtin for cd {
 
         std::mem::swap(&mut dir, &mut se.lock().unwrap().prev_path);
 
-        let target_path: BString = match args.get(0).map(|v| &v[..]) {
+        let target_path: BString = match args.first().map(|v| &v[..]) {
             Some(b"-") => dir,
             Some(path) => path.to_vec(),
             None => {
@@ -79,7 +79,7 @@ impl Builtin for cd {
             }
         };
 
-        if let Err(_) = set_current_dir(OsStr::from_bytes(&target_path)) {
+        if set_current_dir(OsStr::from_bytes(&target_path)).is_err() {
             write!(stdout, "failed to cd into ")?;
             stdout.write_all(&target_path)?;
             writeln!(stdout, "\n")?;
@@ -149,7 +149,7 @@ impl Builtin for Sink {
         stdin: &mut dyn Read,
         _stdout: &mut dyn Write,
     ) -> Result {
-        let Some(path) = args.get(0) else {
+        let Some(path) = args.first() else {
             return Err(Error::Exit(1));
         };
         let path = PathBuf::from(OsStr::from_bytes(path));
@@ -180,7 +180,7 @@ impl Builtin for from {
         _stdin: &mut dyn Read,
         stdout: &mut dyn Write,
     ) -> Result {
-        let Some(path) = args.get(0) else {
+        let Some(path) = args.first() else {
             return Err(Error::Exit(1));
         };
         let path = PathBuf::from(OsStr::from_bytes(path));
@@ -289,10 +289,8 @@ impl Builtin for history {
 
         let path_prefix = if args.here {
             Some(current_dir()?.as_os_str().as_bytes().to_vec())
-        } else if let Some(path) = args.at {
-            Some(path.as_os_str().as_bytes().to_vec())
         } else {
-            None
+            args.at.map(|path| path.as_os_str().as_bytes().to_vec())
         };
 
         let min_time = None;
@@ -312,12 +310,12 @@ impl Builtin for history {
             )
         } else {
             let Ok(hist) = crate::history::HistoryQueryer::new() else {
-                write!(stdout, "error opening global history file\n")?;
+                writeln!(stdout, "error opening global history file")?;
                 return Err(Error::Exit(-1));
             };
 
             let Ok(it) = hist.query(min_time, max_time, path_prefix.as_deref(), args.strict) else {
-                write!(stdout, "error querying global history\n")?;
+                writeln!(stdout, "error querying global history")?;
                 return Err(Error::Exit(-1));
             };
 
diff --git a/src/run/mod.rs b/src/run/mod.rs
index 6234b96..5666574 100644
--- a/src/run/mod.rs
+++ b/src/run/mod.rs
@@ -25,7 +25,7 @@ impl ExecError {
     pub fn error_message(&self) -> String {
         match self {
             ExecError::UnknownVariable(items) => {
-                format!("unknown variable: {}", String::from_utf8_lossy(&items))
+                format!("unknown variable: {}", String::from_utf8_lossy(items))
             }
             ExecError::ExecError(exit_code) => format!("{exit_code}"),
             ExecError::SpawnIO(cmd, error) => match error.kind() {
@@ -43,8 +43,8 @@ impl ExecError {
                 io::ErrorKind::InvalidFilename => {
                     format!("{cmd} is not a valid file name")
                 }
-                io::ErrorKind::ArgumentListTooLong => format!("too many arguments"),
-                io::ErrorKind::Interrupted => format!("got interrupted"),
+                io::ErrorKind::ArgumentListTooLong => String::from("too many arguments"),
+                io::ErrorKind::Interrupted => String::from("got interrupted"),
                 io::ErrorKind::Unsupported => format!("{cmd} is not supported"),
                 e => format!("I am surprised you can get this error here: {e:?}"),
             },
@@ -335,18 +335,17 @@ impl parse::Expander for Executor {
             return Err(ExecError::UnknownVariable(var));
         }
 
-        if var[0].is_ascii_digit() {
-            if let Some(x) = String::from_utf8(var.clone())
+        if var[0].is_ascii_digit()
+            && let Some(x) = String::from_utf8(var.clone())
                 .ok()
                 .and_then(|x| x.parse::<usize>().ok())
-            {
-                if let Some(args) = &self.args {
-                    if x < args.len() {
-                        return Ok(args[x].clone());
-                    }
-                } else if let Some(arg) = std::env::args_os().skip(x).next() {
-                    return Ok(arg.into_encoded_bytes());
+        {
+            if let Some(args) = &self.args {
+                if x < args.len() {
+                    return Ok(args[x].clone());
                 }
+            } else if let Some(arg) = std::env::args_os().nth(x) {
+                return Ok(arg.into_encoded_bytes());
             }
         }