mv: trigger an error when doing mv dir1 dir2 dir2

src/uu/mv/src/mv.rs

@@ -285,7 +285,23 @@ fn exec(files: &[OsString], b: &Behavior) -> UResult<()> {
                 ));
             }
             let target_dir = paths.last().unwrap();
-            move_files_into_dir(&paths[..paths.len() - 1], target_dir, b)
+            let sources = &paths[..paths.len() - 1];
+
+            // Check if we have mv dir1 dir2 dir2
+            // And generate an error if this is the case
+            if sources.contains(target_dir) {
+                return Err(USimpleError::new(
+                    1,
+                    format!(
+                        "cannot move {} to a subdirectory of itself, '{}/{}'",
+                        target_dir.quote(),
+                        target_dir.display(),
+                        target_dir.display()
+                    ),
+                ));
+            }
+
+            move_files_into_dir(sources, target_dir, b)
         }
     }
 }

tests/by-util/test_mv.rs

@@ -823,6 +823,24 @@ fn test_mv_interactive_error() {
         .is_empty());
 }
 
+#[test]
+fn test_mv_info_self() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+    let dir1 = "dir1";
+    let dir2 = "dir2";
+    at.mkdir(dir1);
+    at.mkdir(dir2);
+
+    scene
+        .ucmd()
+        .arg(dir1)
+        .arg(dir2)
+        .arg(dir2)
+        .fails()
+        .stderr_contains("mv: cannot move 'dir2' to a subdirectory of itself, 'dir2/dir2'");
+}
+
 // Todo:
 
 // $ at.touch a b