Moved factor to use clap

Issue: https://github.com/uutils/coreutils/issues/2121

Cargo.lock

@@ -2054,6 +2054,7 @@ dependencies = [
 name = "uu_factor"
 version = "0.0.6"
 dependencies = [
+ "clap",
  "coz",
  "num-traits",
  "paste",

src/uu/factor/Cargo.toml

@@ -21,6 +21,7 @@ rand = { version = "0.7", features = ["small_rng"] }
 smallvec = { version = "0.6.14, < 1.0" }
 uucore = { version = ">=0.0.8", package = "uucore", path = "../../uucore" }
 uucore_procs = { version = ">=0.0.5", package = "uucore_procs", path = "../../uucore_procs" }
+clap = "2.33"
 
 [dev-dependencies]
 paste = "0.1.18"

src/uu/factor/src/cli.rs

@@ -13,18 +13,21 @@ use std::error::Error;
 use std::io::{self, stdin, stdout, BufRead, Write};
 
 mod factor;
+use clap::{App, Arg};
 pub use factor::*;
-use uucore::InvalidEncodingHandling;
 
 mod miller_rabin;
 pub mod numeric;
 mod rho;
 pub mod table;
 
-static SYNTAX: &str = "[OPTION] [NUMBER]...";
-static SUMMARY: &str = "Print the prime factors of the given number(s).
- If none are specified, read from standard input.";
-static LONG_HELP: &str = "";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
+static SUMMARY: &str = "Print the prime factors of the given NUMBER(s).
+If none are specified, read from standard input.";
+
+mod options {
+    pub static NUMBER: &str = "NUMBER";
+}
 
 fn print_factors_str(num_str: &str, w: &mut impl io::Write) -> Result<(), Box<dyn Error>> {
     num_str
@@ -34,14 +37,21 @@ fn print_factors_str(num_str: &str, w: &mut impl io::Write) -> Result<(), Box<dy
 }
 
 pub fn uumain(args: impl uucore::Args) -> i32 {
-    let matches = app!(SYNTAX, SUMMARY, LONG_HELP).parse(
-        args.collect_str(InvalidEncodingHandling::Ignore)
-            .accept_any(),
-    );
+    let matches = App::new(executable!())
+        .version(VERSION)
+        .about(SUMMARY)
+        .arg(Arg::with_name(options::NUMBER).multiple(true))
+        .get_matches_from(args);
     let stdout = stdout();
     let mut w = io::BufWriter::new(stdout.lock());
 
-    if matches.free.is_empty() {
+    if let Some(values) = matches.values_of(options::NUMBER) {
+        for number in values {
+            if let Err(e) = print_factors_str(number, &mut w) {
+                show_warning!("{}: {}", number, e);
+            }
+        }
+    } else {
         let stdin = stdin();
 
         for line in stdin.lock().lines() {
@@ -51,12 +61,6 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 }
             }
         }
-    } else {
-        for number in &matches.free {
-            if let Err(e) = print_factors_str(number, &mut w) {
-                show_warning!("{}: {}", number, e);
-            }
-        }
     }
 
     if let Err(e) = w.flush() {

tests/by-util/test_factor.rs

@@ -39,6 +39,18 @@ fn test_first_100000_integers() {
     assert_eq!(hash_check, "4ed2d8403934fa1c76fe4b84c5d4b8850299c359");
 }
 
+#[test]
+fn test_cli_args() {
+    // Make sure that factor works with CLI arguments as well.
+    new_ucmd!().args(&["3"]).succeeds().stdout_contains("3: 3");
+
+    new_ucmd!()
+        .args(&["3", "6"])
+        .succeeds()
+        .stdout_contains("3: 3")
+        .stdout_contains("6: 2 3");
+}
+
 #[test]
 fn test_random() {
     use conv::prelude::*;