Add unit test for item rename

CHANGELOG.md

@@ -43,6 +43,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   (<https://github.com/openvinotoolkit/datumaro/pull/1223>)
 - Handling undefined labels at the annotation statistics
   (<https://github.com/openvinotoolkit/datumaro/pull/1232>)
+- Add unit test for item rename
+  (<https://github.com/openvinotoolkit/datumaro/pull/1237>)
 
 ## 16/11/2023 - Release 1.5.1
 ### Enhancements

docs/source/docs/command-reference/context_free/transform.md

@@ -157,7 +157,7 @@ Examples:
 
 - Remove the `frame_` prefix from item ids
   ```console
-  datum transform -t rename -- -e "|^frame_|\1|"
+  datum transform -t rename -- -e "|^frame_|"
   ```
 
 - Collect images from subdirectories into the base image directory using regex

tests/unit/test_transforms.py

@@ -582,6 +582,25 @@ def test_random_split_gives_error_on_wrong_ratios(self):
                 ],
             )
 
+    @mark_requirement(Requirements.DATUM_GENERAL_REQ)
+    def test_rename_item(self):
+        src_dataset = Dataset.from_iterable(
+            [
+                DatasetItem(id="frame_1"),
+                DatasetItem(id="frame_2"),
+                DatasetItem(id="frame_3"),
+            ]
+        )
+        expected = Dataset.from_iterable(
+            [
+                DatasetItem(id="1"),
+                DatasetItem(id="2"),
+                DatasetItem(id="3"),
+            ]
+        )
+        actual = transforms.Rename(src_dataset, "|^frame_|")
+        compare_datasets(self, expected, actual)
+
     @mark_requirement(Requirements.DATUM_GENERAL_REQ)
     def test_remap_labels(self):
         src_dataset = Dataset.from_iterable(