fix: log error messages properly on permission errors

src/uu/mv/src/mv.rs

@@ -291,12 +291,22 @@ fn exec(files: &[PathBuf], b: Behavior) -> i32 {
 
                     return match rename(source, target, &b) {
                         Err(e) => {
+                            let error_as_str = e.to_string();
+                            let is_perm_denied = error_as_str.contains("Permission denied");
+                            match e.kind() {
+                                _ => {
                                     show_error!(
                                         "cannot move ‘{}’ to ‘{}’: {}",
                                         source.display(),
                                         target.display(),
-                                e
+                                        if is_perm_denied {
+                                            "Permission denied".to_string()
+                                        } else {
+                                            e.to_string()
+                                        }
                                     );
+                                }
+                            }
                             1
                         }
                         _ => 0,
@@ -357,15 +367,22 @@ fn move_files_into_dir(files: &[PathBuf], target_dir: &Path, b: &Behavior) -> i3
         };
 
         if let Err(e) = rename(sourcepath, &targetpath, b) {
+            let error_as_str = e.to_string();
+            let is_perm_denied = error_as_str.contains("Permission denied");
             show_error!(
-                "mv: cannot move ‘{}’ to ‘{}’: {}",
+                "cannot move ‘{}’ to ‘{}’: {}",
                 sourcepath.display(),
                 targetpath.display(),
-                e
+                if is_perm_denied {
+                    "Permission denied".to_string()
+                } else {
+                    e.to_string()
+                }
             );
             all_successful = false;
         }
     }
+
     if all_successful {
         0
     } else {

tests/by-util/test_mv.rs

@@ -587,6 +587,24 @@ fn test_mv_verbose() {
         ));
 }
 
+#[test]
+fn test_mv_permission_error() {
+    let scene = TestScenario::new("mkdir");
+    let folder1 = "bar";
+    let folder2 = "foo";
+    let folder_to_move = "bar/foo";
+    scene.ucmd().arg("-m444").arg(folder1).succeeds();
+    scene.ucmd().arg("-m777").arg(folder2).succeeds();
+
+    scene
+        .cmd_keepenv(util_name!())
+        .arg(folder2)
+        .arg(folder_to_move)
+        .run()
+        .stderr_str()
+        .ends_with("Permission denied");
+}
+
 // Todo:
 
 // $ at.touch a b