feat: add the seq command

coreutils/src/commands/mod.rs

@@ -22,3 +22,4 @@ command!(hostname::Hostname);
 command!(tee::Tee);
 command!(base64::Base64);
 command!(base32::Base32);
+command!(seq::Seq);

coreutils/src/commands/seq.rs

@@ -0,0 +1,66 @@
+use boxutils::{args::ArgParser, commands::Command};
+
+pub struct Seq;
+
+impl Command for Seq {
+    fn execute(&self) {
+        let args = ArgParser::builder()
+            .add_option("-s")
+            .add_flag("-w")
+            .parse_args("seq");
+
+        let pad_with_zeroes = args.get_flag("-w");
+        let separator = args.get_option("-s").unwrap_or("\n");
+
+        // note(teesh): I do not know why Rust considers this
+        //              "unused", so I'm just gonna make it shut
+        //              up about it haha
+        #[allow(unused_assignments)]
+        let (mut firstnum, mut incnum, mut lastnum) = (1, 1, 0);
+
+        match &args.get_normal_args()[..] {
+            [last] => {
+                lastnum = last.parse().expect("seq: invalid last number");
+            }
+            [first, last] => {
+                firstnum = first.parse().expect("seq: invalid first number");
+                lastnum = last.parse().expect("seq: invalid last number");
+            }
+            [first, inc, last] => {
+                firstnum = first.parse().expect("seq: invalid first number");
+                incnum = inc.parse().expect("seq: invalid inc number");
+                lastnum = last.parse().expect("seq: invalid last number");
+            }
+            _ => panic!("seq: malformed arguments"),
+        }
+
+        let mut accumulator = firstnum;
+
+        // Find the width of the largest number
+        let width = if pad_with_zeroes {
+            // Calculate width based on the largest number in the sequence
+            let max_value = if lastnum > firstnum {
+                lastnum
+            } else {
+                firstnum
+            };
+            max_value.to_string().len()
+        } else {
+            0 // no padding if not using -w
+        };
+
+        while accumulator <= lastnum {
+            // If padding is enabled, format the number with leading zeros
+            if pad_with_zeroes {
+                print!("{:0width$}", accumulator, width = width);
+            } else {
+                print!("{}", accumulator);
+            }
+
+            accumulator += incnum;
+            if accumulator <= lastnum {
+                print!("{}", separator);
+            }
+        }
+    }
+}

src/registry.rs

@@ -32,6 +32,7 @@ pub fn get_registry() -> CommandRegistry {
         "tee" => coreutils::commands::Tee,
         "base64" => coreutils::commands::Base64,
         "base32" => coreutils::commands::Base32,
+        "seq" => coreutils::commands::Seq,
         "box" => Boxcmd
     });