Remove some allocations

src/cmd/base32/mod.rs

@@ -24,11 +24,6 @@ impl Cmd for Base32 {
         let Some(matches) = matches else {
             return Err(io::Error::new(io::ErrorKind::Other, "No input").into());
         };
-        let files: Vec<_> = match matches.get_many::<String>("INPUT") {
-            Some(c) => c.cloned().collect(),
-            None => vec![String::from("-")],
-        };
-        let len = files.len();
         let color = match matches.get_one::<String>("color").map(String::as_str) {
             Some("always") => ColorChoice::Always,
             Some("ansi") => ColorChoice::AlwaysAnsi,
@@ -41,6 +36,8 @@ impl Cmd for Base32 {
             }
             _ => ColorChoice::Never,
         };
+        if let Some(files) = matches.get_many::<String>("files") {
+            let (len, _) = files.size_hint();
             for (index, file) in files.into_iter().enumerate() {
                 if { len > 1 || matches.get_flag("verbose") } && !matches.get_flag("QUIET") {
                     let mut stdout = StandardStream::stdout(color);
@@ -62,12 +59,15 @@ impl Cmd for Base32 {
                         match matches.get_one::<usize>("WRAP") {
                             Some(c) => *c,
                             None => {
-                            return Err(io::Error::new(io::ErrorKind::Other, "Invalid wrap").into())
+                                return Err(
+                                    io::Error::new(io::ErrorKind::Other, "Invalid wrap").into()
+                                )
                             }
                         },
                     );
                 }
             }
+        }
         Ok(())
     }
 
@@ -80,7 +80,8 @@ pub fn args() -> [Arg; 7] {
     [
         Arg::new("INPUT")
             .help("The input file to use")
-            .num_args(1..),
+            .num_args(1..)
+            .default_value("-"),
         Arg::new("DECODE")
             .help("Decode rather than encode")
             .short('d')

src/cmd/base64/mod.rs

@@ -23,11 +23,6 @@ impl Cmd for Base64 {
         let Some(matches) = matches else {
             return Err(Box::new(io::Error::new(io::ErrorKind::Other, "No input")));
         };
-        let files: Vec<_> = match matches.get_many::<String>("INPUT") {
-            Some(c) => c.cloned().collect(),
-            None => vec![String::from("-")],
-        };
-        let len = files.len();
         let color = match matches.get_one::<String>("color").map(String::as_str) {
             Some("always") => ColorChoice::Always,
             Some("ansi") => ColorChoice::AlwaysAnsi,
@@ -40,7 +35,9 @@ impl Cmd for Base64 {
             }
             _ => ColorChoice::Never,
         };
-        for (index, file) in files.into_iter().enumerate() {
+        if let Some(files) = matches.get_many::<String>("INPUT") {
+            let (len, _) = files.size_hint();
+            for (index, file) in files.enumerate() {
                 if { len > 1 || matches.get_flag("VERBOSE") } && !matches.get_flag("QUIET") {
                     let mut stdout = StandardStream::stdout(color);
                     stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)))?;
@@ -65,6 +62,7 @@ impl Cmd for Base64 {
                     );
                 }
             }
+        }
         Ok(())
     }
 

src/cmd/head/mod.rs

@@ -25,6 +25,7 @@ impl Cmd for Head {
             .args([
                 Arg::new("FILES")
                     .help("The input file to use")
+                    .default_value("-")
                     .num_args(1..),
                 Arg::new("BYTES")
                     .help("Count bytes instead of lines")
@@ -44,7 +45,10 @@ impl Cmd for Head {
                     .allow_negative_numbers(false)
                     .conflicts_with("num")
                     .value_parser(value_parser!(usize)),
-                args::color(),
+                Arg::new("color")
+                    .short('C')
+                    .long("color")
+                    .value_parser(["always", "ansi", "auto", "never"]),
                 Arg::new("num")
                     .short('1')
                     .short_aliases(['2', '3', '4', '5', '6', '7', '8', '9'])
@@ -82,12 +86,6 @@ impl Cmd for Head {
         if let Some(l) = matches.get_one("LINES") {
             lines = *l;
         }
-        let files = match matches.get_many::<String>("FILES") {
-            Some(c) => c.map(std::string::ToString::to_string).collect(),
-            None => vec!["-".to_string()],
-        };
-        let header =
-            !matches.get_flag("QUIET") && { files.len() > 1 || matches.get_flag("HEADER") };
         let color = match matches.get_one::<String>("color").map(String::as_str) {
             Some("always") => ColorChoice::Always,
             Some("ansi") => ColorChoice::AlwaysAnsi,
@@ -100,11 +98,15 @@ impl Cmd for Head {
             }
             _ => ColorChoice::Never,
         };
-        for (index, file) in files.into_iter().enumerate() {
+        if let Some(files) = matches.get_many::<String>("FILES") {
+            let (len, _) = files.size_hint();
+            let header = !matches.get_flag("QUIET") && { len > 1 || matches.get_flag("HEADER") };
+            for (index, file) in files.enumerate() {
                 if index == 1 && header {
                     println!();
                 }
-            head(&file, lines, header, matches.get_flag("BYTES"), color)?;
+                head(file, lines, header, matches.get_flag("BYTES"), color)?;
+            }
         }
         Ok(())
     }

src/cmd/mod.rs

@@ -16,6 +16,7 @@ mod date;
 mod dd;
 mod dirname;
 mod echo;
+mod expand;
 mod factor;
 mod r#false;
 mod fold;

src/cmd/rev/mod.rs

@@ -20,7 +20,8 @@ impl Cmd for Rev {
                 args::color(),
                 Arg::new("file")
                     .help("if file is '-' read from stdin")
-                    .num_args(0..),
+                    .num_args(1..)
+                    .default_value("-"),
             ])
     }
 
@@ -28,10 +29,6 @@ impl Cmd for Rev {
         let Some(matches) = matches else {
             return Err(Box::new(io::Error::new(ErrorKind::Other, "No input")));
         };
-        let files: Vec<_> = match matches.get_many::<String>("file") {
-            Some(c) => c.cloned().collect(),
-            None => vec![String::from("-")],
-        };
         let color = match matches.get_one::<String>("color").map(String::as_str) {
             Some("always") => ColorChoice::Always,
             Some("ansi") => ColorChoice::AlwaysAnsi,
@@ -44,8 +41,9 @@ impl Cmd for Rev {
             }
             _ => ColorChoice::Never,
         };
-        for (index, file) in files.into_iter().enumerate() {
+        if let Some(files) = matches.get_many::<String>("file") {
-            if matches.get_flag("header") {
+            for (index, file) in files.enumerate() {
+                if matches.get_flag("HEADER") {
                     let mut stdout = StandardStream::stdout(color);
                     stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)))?;
                     match index {
@@ -56,6 +54,7 @@ impl Cmd for Rev {
                 }
                 rev_file(&file)?;
             }
+        }
         Ok(())
     }