sh: fix clippy warnings

Author: grisenti

sh/src/builtin/alias.rs

@@ -34,12 +34,10 @@ impl BuiltinUtility for AliasBuiltin {
                 shell
                     .alias_table
                     .insert(alias.to_string(), command.to_string());
+            } else if let Some(command) = shell.alias_table.get(arg) {
+                opened_files.write_out(format!("alias {}='{}'", arg, command));
             } else {
-                if let Some(command) = shell.alias_table.get(arg) {
-                    opened_files.write_out(format!("alias {}='{}'", arg, command));
-                } else {
-                    return Err(format!("alias: {}: not found", arg).into());
-                }
+                return Err(format!("alias: {}: not found", arg).into());
             }
         }
         Ok(0)

sh/src/builtin/bg.rs

@@ -57,7 +57,7 @@ impl BuiltinUtility for Bg {
                     status = 1;
                 }
             } else {
-                opened_files.write_err("bg: no background jobs".to_string());
+                opened_files.write_err("bg: no background jobs");
                 status = 1;
             }
         } else {

sh/src/builtin/cd.rs

@@ -86,14 +86,12 @@ impl BuiltinUtility for Cd {
             } => {
                 let dir = if let Some(dir) = directory {
                     dir
+                } else if let Some(home_dir) = shell.environment.get_str_value("HOME") {
+                    home_dir
                 } else {
-                    if let Some(home_dir) = shell.environment.get_str_value("HOME") {
-                        home_dir
-                    } else {
-                        // behaviour is implementation defined, bash just returns 0
-                        // and doesn't change directory
-                        return Ok(0);
-                    }
+                    // behaviour is implementation defined, bash just returns 0
+                    // and doesn't change directory
+                    return Ok(0);
                 };
                 let mut curr_path = OsString::new();
 
@@ -122,7 +120,7 @@ impl BuiltinUtility for Cd {
                 }
 
                 if !handle_dot_dot_physically {
-                    if !curr_path.as_bytes().get(0).is_some_and(|c| *c == b'/') {
+                    if !curr_path.as_bytes().first().is_some_and(|c| *c == b'/') {
                         let mut new_curr_path = shell
                             .environment
                             .get_str_value("PWD")

sh/src/builtin/command.rs

@@ -131,7 +131,7 @@ impl BuiltinUtility for Command {
                     args.command_name
                 ))
             }
-        } else if shell.functions.get(args.command_name).is_some() {
+        } else if shell.functions.contains_key(args.command_name) {
             if args.action == Action::PrintShort {
                 opened_files.write_out(format!("{}\n", args.command_name))
             } else {

sh/src/builtin/control_flow.rs

@@ -30,7 +30,7 @@ fn loop_control_flow(
     if args.len() > 1 {
         return Err(format!("{name}: too many arguments").into());
     }
-    let n = if let Some(n) = args.get(0) {
+    let n = if let Some(n) = args.first() {
         match n.parse::<i32>() {
             Ok(n) => n,
             Err(_) => {
@@ -74,7 +74,7 @@ impl SpecialBuiltinUtility for Return {
         if args.len() > 1 {
             return Err("return: too many arguments".into());
         }
-        let n = if let Some(n) = args.get(0) {
+        let n = if let Some(n) = args.first() {
             match n.parse::<i32>() {
                 Ok(n) => n,
                 Err(_) => {

sh/src/builtin/exec.rs

@@ -30,6 +30,6 @@ impl SpecialBuiltinUtility for Exec {
             .find_command(&args[0], "", true)
             .ok_or(format!("exec: {}: command not found", args[0]))?;
 
-        shell.exec(command, &args, opened_files)
+        shell.exec(command, args, opened_files)
     }
 }

sh/src/builtin/exit.rs

@@ -20,7 +20,7 @@ impl SpecialBuiltinUtility for Exit {
             return Err("exit: too many arguments".into());
         }
 
-        if let Some(arg) = args.get(0) {
+        if let Some(arg) = args.first() {
             if let Ok(n) = arg.parse::<i32>() {
                 shell.exit(n);
             } else {

sh/src/builtin/export.rs

@@ -21,7 +21,7 @@ impl SpecialBuiltinUtility for Export {
         shell: &mut Shell,
         opened_files: &mut OpenedFiles,
     ) -> BuiltinResult {
-        if args.get(0).is_some_and(|arg| arg == "-p") {
+        if args.first().is_some_and(|arg| arg == "-p") {
             if args.len() > 1 && !(args.len() == 2 && args[1] == "--") {
                 return Err("export: too many arguments".into());
             }
@@ -55,7 +55,7 @@ impl SpecialBuiltinUtility for Export {
                 }
                 (name.to_string(), Some(value[1..].to_string()))
             } else {
-                if !is_valid_name(&arg) {
+                if !is_valid_name(arg) {
                     return Err(format!("export: '{arg}' is not a valid name\n").into());
                 }
                 (arg.clone(), None)

sh/src/builtin/fc.rs

@@ -112,10 +112,7 @@ impl<'s> FcArgs<'s> {
             let mut replace = None;
             let mut first = None;
             if let Some(first_op) = args.get(first_operand) {
-                if first_op.contains('=') {
-                    let mut split = first_op.splitn(2, '=');
-                    let old = split.next().unwrap();
-                    let new = split.next().unwrap();
+                if let Some((old, new)) = first_op.split_once('=') {
                     replace = Some(Replace { old, new });
                 } else {
                     first = Some(EndPoint::parse(first_op));

sh/src/builtin/fg.rs

@@ -26,7 +26,7 @@ fn run_foreground_job(
         kill(job.pid, nix::sys::signal::SIGCONT)
             .map_err(|err| format!("fg: failed to resume {arg} ({err})"))?;
     }
-    opened_files.write_out(&format!("{}\n", job.command));
+    opened_files.write_out(format!("{}\n", job.command));
     let mut temp = job.command.clone();
     std::mem::swap(&mut shell.last_pipeline_command, &mut temp);
     shell
@@ -63,7 +63,7 @@ impl BuiltinUtility for Fg {
                     status = 1;
                 }
             } else {
-                opened_files.write_err("bg: no background jobs".to_string());
+                opened_files.write_err("bg: no background jobs");
                 status = 1;
             }
         } else {