ls: simplify tab size parsing and loop the tabsize tests

src/uu/ls/src/config.rs

@@ -669,7 +669,7 @@ fn parse_width(width_match: Option<&String>) -> Result<u16, LsError> {
 }
 
 /// Parses the tab size value from the command line
-fn parse_tab_size(size_str: &str) -> Result<usize, Box<LsError>> {
+fn parse_tab_size(size_str: &str) -> Result<usize, LsError> {
     size_str
         .parse::<usize>()
         .ok()
@@ -679,7 +679,7 @@ fn parse_tab_size(size_str: &str) -> Result<usize, Box<LsError>> {
                 .or_else(|| size_str.strip_prefix("0X"))
                 .and_then(|hex| usize::from_str_radix(hex, 16).ok())
         })
-        .ok_or_else(|| Box::new(LsError::InvalidTabSize(size_str.to_string())))
+        .ok_or_else(|| LsError::InvalidTabSize(size_str.to_string()))
 }
 
 impl Config {
@@ -976,10 +976,7 @@ impl Config {
         let tab_size = if needs_color {
             Some(0)
         } else if let Some(size_str) = options.get_one::<String>(options::format::TAB_SIZE) {
-            match parse_tab_size(size_str) {
-                Ok(n) => Some(n),
-                Err(e) => return Err(e),
-            }
+            Some(parse_tab_size(size_str)?)
         } else {
             None
         };

tests/by-util/test_ls.rs

@@ -5297,24 +5297,17 @@ fn test_symlink_target_extension_color() {
 fn test_tabsize_option() {
     let scene = TestScenario::new(util_name!());
 
-    scene.ucmd().args(&["-T", "3"]).succeeds();
+    for valid in ["3", "0", "0xff"] {
+        scene.ucmd().args(&["-T", valid]).succeeds();
+    }
     scene.ucmd().args(&["--tabsize", "0"]).succeeds();
-    scene
-        .ucmd()
-        .arg("--tabsize=-3")
-        .fails()
-        .stderr_is("ls: invalid tab size: '-3'\n");
-    scene
-        .ucmd()
-        .arg("--tabsize=a")
-        .fails()
-        .stderr_is("ls: invalid tab size: 'a'\n");
-    scene
-        .ucmd()
-        .arg("--tabsize=3.14")
-        .fails()
-        .stderr_is("ls: invalid tab size: '3.14'\n");
-    scene.ucmd().args(&["-T", "0xff"]).succeeds();
+    for invalid in ["-3", "a", "3.14"] {
+        scene
+            .ucmd()
+            .arg(format!("--tabsize={invalid}"))
+            .fails()
+            .stderr_is(format!("ls: invalid tab size: '{invalid}'\n"));
+    }
     scene.ucmd().arg("-T").fails();
 }