Add `wc` applet; Add `Bitflags` trait;

README.md

@@ -54,6 +54,7 @@ code between applets, making for an overall smaller binary.
 - sync
 - true
 - unlink
+- wc
 - which
 - whoami
 - yes

src/args/mod.rs

@@ -1,3 +1,5 @@
+//! Common arguments to be re-used across multiple commands. Using these args
+//! instead of implementing from scratch increases consistency across applets
 use clap::{Arg, ArgAction};
 
 pub fn verbose() -> Arg {

src/bitflags/mod.rs

@@ -0,0 +1,62 @@
+//! Minimal bitflags type implementation allowing to check if a set of flags
+//! contains a specific flag. The type must implement Copy and Bitand with u32.
+use core::ops::BitAnd;
+
+pub trait BitFlags<T> {
+    fn contains(&self, rhs: T) -> bool;
+}
+
+impl<T, U> BitFlags<T> for U
+where
+    U: BitAnd<T> + Copy,
+    T: BitAnd<U>,
+    <U as BitAnd<T>>::Output: PartialEq<u32>,
+{
+    fn contains(&self, rhs: T) -> bool {
+        *self & rhs != 0
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[derive(Clone, Copy)]
+    enum Flags {
+        A = 0b1,
+        B = 0b10,
+        C = 0b100,
+    }
+
+    impl BitAnd<Flags> for u32 {
+        type Output = u32;
+
+        fn bitand(self, rhs: Flags) -> Self::Output {
+            self & rhs as u32
+        }
+    }
+
+    impl BitAnd<u32> for Flags {
+        type Output = u32;
+
+        fn bitand(self, rhs: u32) -> Self::Output {
+            self as u32 & rhs
+        }
+    }
+
+    impl BitAnd for Flags {
+        type Output = u32;
+
+        fn bitand(self, rhs: Self) -> Self::Output {
+            self as u32 & rhs as u32
+        }
+    }
+
+    #[test]
+    fn contains() {
+        let num = 0b101;
+        assert!(num.contains(Flags::A));
+        assert!(!num.contains(Flags::B));
+        assert!(num.contains(Flags::C));
+    }
+}

src/cmd/mod.rs

@@ -45,6 +45,7 @@ mod sleep;
 mod sync;
 mod r#true;
 mod unlink;
+mod wc;
 mod which;
 mod whoami;
 mod yes;
@@ -104,6 +105,7 @@ pub fn get(name: &str) -> Option<Box<dyn Cmd>> {
         "sync" => Some(Box::new(sync::Sync::default())),
         "true" => Some(Box::new(r#true::True::default())),
         "unlink" => Some(Box::new(unlink::Unlink::default())),
+        "wc" => Some(Box::new(wc::Wc::default())),
         "which" => Some(Box::new(which::Which::default())),
         "whoami" => Some(Box::new(whoami::Whoami::default())),
         "yes" => Some(Box::new(yes::Yes::default())),
@@ -111,7 +113,7 @@ pub fn get(name: &str) -> Option<Box<dyn Cmd>> {
     }
 }
 
-pub static COMMANDS: [&str; 40] = [
+pub static COMMANDS: [&str; 41] = [
     "base32",
     "base64",
     "basename",
@@ -149,6 +151,7 @@ pub static COMMANDS: [&str; 40] = [
     "sync",
     "true",
     "unlink",
+    "wc",
     "which",
     "whoami",
     "yes",

src/cmd/wc/mod.rs

@@ -0,0 +1,246 @@
+use super::Cmd;
+use crate::bitflags::BitFlags;
+use clap::{Arg, ArgMatches, Command, ArgAction};
+use std::{
+    cmp,
+    error::Error,
+    fmt::{self, Write},
+    fs,
+    io::{self, stdin, Read},
+    ops::{BitAnd, BitAndAssign, BitOr, BitOrAssign, AddAssign},
+    str::FromStr,
+};
+
+#[derive(Debug, Default)]
+pub struct Wc;
+
+impl Cmd for Wc {
+    fn cli(&self) -> clap::Command {
+        Command::new("wc")
+            .version(env!("CARGO_PKG_VERSION"))
+            .author("Nathan Fisher")
+            .about("Print newline, word, and byte counts for each file")
+            .args([
+                Arg::new("INPUT")
+                    .help("The input file to use")
+                    .num_args(1..),
+                Arg::new("BYTES")
+                    .help("Print the byte counts")
+                    .short('c')
+                    .long("bytes")
+                    .action(ArgAction::SetTrue),
+                Arg::new("CHARS")
+                    .help("Print the character counts")
+                    .short('m')
+                    .long("chars")
+                    .action(ArgAction::SetTrue),
+                Arg::new("LINES")
+                    .help("Print the line counts")
+                    .short('l')
+                    .long("lines")
+                    .action(ArgAction::SetTrue),
+                Arg::new("MAX")
+                    .help("Print the maximum display width")
+                    .short('L')
+                    .long("max-line-length")
+                    .action(ArgAction::SetTrue),
+                Arg::new("WORDS")
+                    .help("Print the word counts")
+                    .short('w')
+                    .long("words")
+                    .action(ArgAction::SetTrue),
+            ])
+    }
+
+    fn run(&self, matches: Option<&ArgMatches>) -> Result<(), Box<dyn Error>> {
+        let Some(matches) = matches else {
+            return Err(io::Error::new(io::ErrorKind::Other, "no input").into());
+        };
+        let mut flags = 0;
+        for arg in &["LINES", "WORDS", "CHARS", "BYTES", "MAX"] {
+            if matches.get_flag(arg) {
+                flags |= arg.parse::<Flags>()?;
+            }
+        }
+        if flags == 0 {
+            flags = 0b1011;
+        }
+        let files: Vec<_> = match matches.get_many::<String>("INPUT") {
+            Some(c) => c.map(|x| x.to_owned()).collect(),
+            None => vec!["-".to_string()],
+        };
+        let mut totals = Values {
+            name: "Total",
+            ..Values::default()
+        };
+        files.iter().try_for_each(|f| get_values(f, &mut totals, flags))?;
+        if files.len() > 1 {
+            totals.print_values(flags)?;
+        }
+        Ok(())
+    }
+
+    fn path(&self) -> Option<crate::Path> {
+        Some(crate::Path::UsrBin)
+    }
+}
+
+fn get_values<'a>(file: &'a str, totals: &mut Values<'a>, flags: u32) -> Result<(), Box<dyn Error>> {
+    let contents = if file == "-" {
+        let mut buf = String::new();
+        stdin().read_to_string(&mut buf)?;
+        buf
+    } else {
+        fs::read_to_string(file)?
+    };
+    let mut f = Values {
+        name: file,
+        ..Values::default()
+    };
+    if flags.contains(Flags::Lines) {
+        f.lines = contents.lines().count();
+    }
+    if flags.contains(Flags::Words) {
+        f.words = contents.split_whitespace().count();
+    }
+    if flags.contains(Flags::Chars) {
+        f.chars = contents.chars().count();
+    }
+    if flags.contains(Flags::Bytes) {
+        f.bytes = contents.len();
+    }
+    if flags.contains(Flags::Max) {
+        f.max = 0;
+        contents.lines().into_iter().for_each(|line| {
+            let max = line.chars().count();
+            f.max = cmp::max(max, f.max);
+        });
+    }
+    *totals += f;
+    f.print_values(flags)
+}
+
+#[derive(Clone, Copy, Default)]
+struct Values<'a> {
+    name: &'a str,
+    lines: usize,
+    words: usize,
+    chars: usize,
+    bytes: usize,
+    max: usize,
+}
+
+impl AddAssign for Values<'_> {
+    fn add_assign(&mut self, rhs: Self) {
+        self.lines += rhs.lines;
+        self.words += rhs.words;
+        self.chars += rhs.chars;
+        self.bytes += rhs.bytes;
+        self.max = cmp::max(self.max, rhs.max);
+    }
+}
+
+impl Values<'_> {
+    fn print_values(&self, flags: u32) -> Result<(), Box<dyn Error>> {
+        let mut line = String::new();
+        if flags.contains(Flags::Lines) {
+            write!(line, "\t{}", self.lines)?;
+        }
+        if flags.contains(Flags::Words) {
+            write!(line, "\t{}", self.words)?;
+        }
+        if flags.contains(Flags::Chars) {
+            write!(line, "\t{}", self.chars)?;
+        }
+        if flags.contains(Flags::Bytes) {
+            write!(line, "\t{}", self.bytes)?;
+        }
+        if flags.contains(Flags::Max) {
+            write!(line, "\t{}", self.max)?;
+        }
+        if self.name != "-" {
+            write!(line, "\t{}", self.name).unwrap();
+        }
+        println!("{}", line);
+        Ok(())
+    }
+}
+
+#[derive(Debug)]
+pub struct ParseFlagsError;
+
+impl fmt::Display for ParseFlagsError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{self:?}")
+    }
+}
+
+impl Error for ParseFlagsError {}
+
+#[derive(Clone, Copy)]
+enum Flags {
+    Lines = 0b1,
+    Words = 0b10,
+    Chars = 0b100,
+    Bytes = 0b1000,
+    Max = 0b10000,
+}
+
+impl FromStr for Flags {
+    type Err = ParseFlagsError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "LINES" => Ok(Self::Lines),
+            "WORDS" => Ok(Self::Words),
+            "CHARS" => Ok(Self::Chars),
+            "BYTES" => Ok(Self::Bytes),
+            "MAX" => Ok(Self::Max),
+            _ => Err(ParseFlagsError),
+        }
+    }
+}
+
+impl BitAnd<u32> for Flags {
+    type Output = u32;
+
+    fn bitand(self, rhs: u32) -> Self::Output {
+        self as u32 & rhs
+    }
+}
+
+impl BitAnd<Flags> for u32 {
+    type Output = u32;
+
+    fn bitand(self, rhs: Flags) -> Self::Output {
+        self & rhs as u32
+    }
+}
+
+impl BitAndAssign<Flags> for u32 {
+    fn bitand_assign(&mut self, rhs: Flags) {
+        *self = *self & rhs;
+    }
+}
+
+impl BitOr for Flags {
+    type Output = u32;
+
+    fn bitor(self, rhs: Self) -> Self::Output {
+        self as u32 | rhs as u32
+    }
+}
+
+impl BitOr<Flags> for u32 {
+    type Output = u32;
+
+    fn bitor(self, rhs: Flags) -> Self::Output {
+        self | rhs as u32
+    }
+}
+
+impl BitOrAssign<Flags> for u32 {
+    fn bitor_assign(&mut self, rhs: Flags) {
+        *self = *self | rhs;
+    }
+}

src/lib.rs

@@ -2,6 +2,7 @@
 use std::{env, path::PathBuf, process, string::ToString};
 
 pub mod args;
+pub mod bitflags;
 mod cmd;
 pub mod fs;
 pub mod math;