numfmt: move to thiserror

Cargo.lock

@@ -3032,6 +3032,7 @@ name = "uu_numfmt"
 version = "0.0.30"
 dependencies = [
  "clap",
+ "thiserror 2.0.12",
  "uucore",
 ]
 

src/uu/numfmt/Cargo.toml

@@ -19,6 +19,7 @@ path = "src/numfmt.rs"
 [dependencies]
 clap = { workspace = true }
 uucore = { workspace = true, features = ["ranges"] }
+thiserror = { workspace = true }
 
 [[bin]]
 name = "numfmt"

src/uu/numfmt/src/errors.rs

@@ -3,13 +3,12 @@
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
 
-use std::{
-    error::Error,
-    fmt::{Debug, Display},
-};
+use std::fmt::Debug;
+use thiserror::Error;
 use uucore::error::UError;
 
-#[derive(Debug)]
+#[derive(Debug, Error)]
+#[error("{0}")]
 pub enum NumfmtError {
     IoError(String),
     IllegalArgument(String),
@@ -25,15 +24,3 @@ impl UError for NumfmtError {
         }
     }
 }
-
-impl Error for NumfmtError {}
-
-impl Display for NumfmtError {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match self {
-            Self::IoError(s) | Self::IllegalArgument(s) | Self::FormattingError(s) => {
-                write!(f, "{s}")
-            }
-        }
-    }
-}