feat(task modification precedence): Improving task modification precedence so that all modes can be used in a single run. Adapting tests accordinginly.

tests/datasets/test_dataset_tools.py

@@ -1161,6 +1161,20 @@ def test_modify_tasks_replacements_with_episode_overrides(sample_dataset):
     assert len(modified_dataset.meta.tasks) == 3
 
 
+def test_modify_tasks_default_task_and_replacements(sample_dataset):
+    """Test that new_task acts as the default for episodes not matched by task_replacements."""
+    modified_dataset = modify_tasks(
+        sample_dataset,
+        new_task="Default task",
+        task_replacements={"task_0": "Pick the cube"},
+    )
+
+    for ep_idx in range(5):
+        expected_task = "Pick the cube" if ep_idx % 2 == 0 else "Default task"
+        assert modified_dataset.meta.episodes[ep_idx]["tasks"][0] == expected_task
+    assert len(modified_dataset.meta.tasks) == 2
+
+
 def test_modify_tasks_no_task_specified(sample_dataset):
     """Test error when no task is specified."""
     with pytest.raises(ValueError, match="Must specify at least one of new_task, episode_tasks, or task_replacements"):
@@ -1179,16 +1193,6 @@ def test_modify_tasks_invalid_task_replacements(sample_dataset):
         modify_tasks(sample_dataset, task_replacements={"missing_task": "New task"})
 
 
-def test_modify_tasks_rejects_default_task_and_replacements(sample_dataset):
-    """Test that default-task assignment cannot be combined with find-and-replace."""
-    with pytest.raises(ValueError, match="Cannot combine new_task with task_replacements"):
-        modify_tasks(
-            sample_dataset,
-            new_task="Default task",
-            task_replacements={"task_0": "Pick the cube"},
-        )
-
-
 def test_modify_tasks_updates_info_json(sample_dataset):
     """Test that total_tasks is updated in info.json."""
     episode_tasks = {0: "Task A", 1: "Task B", 2: "Task C", 3: "Task A", 4: "Task B"}

tests/scripts/test_edit_dataset_modify_tasks.py

@@ -1,83 +0,0 @@
-#!/usr/bin/env python
-
-# Copyright 2026 The HuggingFace Inc. team. All rights reserved.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import numpy as np
-import pytest
-
-from lerobot.datasets.lerobot_dataset import LeRobotDataset
-from lerobot.scripts.lerobot_edit_dataset import EditDatasetConfig, ModifyTasksConfig, handle_modify_tasks
-
-
-@pytest.fixture
-def sample_dataset(tmp_path, empty_lerobot_dataset_factory):
-    features = {
-        "action": {"dtype": "float32", "shape": (6,), "names": None},
-        "observation.state": {"dtype": "float32", "shape": (4,), "names": None},
-        "observation.images.top": {"dtype": "image", "shape": (224, 224, 3), "names": None},
-    }
-
-    dataset = empty_lerobot_dataset_factory(
-        root=tmp_path / "test_dataset",
-        features=features,
-    )
-
-    for ep_idx in range(5):
-        for _ in range(10):
-            frame = {
-                "action": np.random.randn(6).astype(np.float32),
-                "observation.state": np.random.randn(4).astype(np.float32),
-                "observation.images.top": np.random.randint(0, 255, size=(224, 224, 3), dtype=np.uint8),
-                "task": f"task_{ep_idx % 2}",
-            }
-            dataset.add_frame(frame)
-        dataset.save_episode()
-
-    dataset.finalize()
-    return dataset
-
-
-def test_handle_modify_tasks_with_replacements(sample_dataset):
-    cfg = EditDatasetConfig(
-        repo_id=sample_dataset.repo_id,
-        root=str(sample_dataset.root),
-        operation=ModifyTasksConfig(
-            task_replacements={
-                "task_0": "Pick the cube",
-                "task_1": "Place the cube",
-            }
-        ),
-    )
-
-    handle_modify_tasks(cfg)
-
-    modified_dataset = LeRobotDataset(cfg.repo_id, root=sample_dataset.root)
-    assert modified_dataset.meta.episodes[0]["tasks"][0] == "Pick the cube"
-    assert modified_dataset.meta.episodes[1]["tasks"][0] == "Place the cube"
-    assert len(modified_dataset.meta.tasks) == 2
-
-
-def test_handle_modify_tasks_rejects_default_task_and_replacements(sample_dataset):
-    cfg = EditDatasetConfig(
-        repo_id=sample_dataset.repo_id,
-        root=str(sample_dataset.root),
-        operation=ModifyTasksConfig(
-            new_task="Default task",
-            task_replacements={"task_0": "Pick the cube"},
-        ),
-    )
-
-    with pytest.raises(ValueError, match="Cannot combine new_task with task_replacements"):
-        handle_modify_tasks(cfg)