Merge remote-tracking branch 'origin/main' into feat/smolvla-on-steerable

Co-authored-by: Cursor <cursoragent@cursor.com>

# Conflicts:
#	src/lerobot/configs/train.py
#	src/lerobot/datasets/__init__.py
#	src/lerobot/policies/factory.py
#	src/lerobot/policies/groot/groot_n1.py
#	src/lerobot/scripts/lerobot_eval.py
#	src/lerobot/scripts/lerobot_train.py
#	uv.lock

tests/configs/test_resume_from_hub.py

@@ -0,0 +1,68 @@
+# Copyright 2025 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 pytest
+
+import lerobot.configs.train as tc
+from lerobot.configs.train import TrainPipelineConfig
+
+
+class _FakeHTTPError(tc.HfHubHTTPError):
+    """HfHubHTTPError that can be raised without a real HTTP response object."""
+
+    def __init__(self):
+        pass
+
+
+def test_from_pretrained_falls_back_to_latest_checkpoint_config(tmp_path, monkeypatch):
+    """A Hub repo with no root train_config.json (an interrupted run that only pushed
+    checkpoints/) resolves via the latest checkpoint's config."""
+    # A real train_config.json written by save_pretrained, to be returned by the fallback.
+    parsed = tc.draccus.parse(TrainPipelineConfig, args=["--dataset.repo_id", "u/d"])
+    cfg_file = tmp_path / "train_config.json"
+    parsed._save_pretrained(tmp_path)
+    assert cfg_file.is_file()
+
+    calls = []
+
+    def fake_hf_hub_download(filename=None, **kwargs):
+        calls.append(filename)
+        if filename == "train_config.json":
+            raise _FakeHTTPError()  # no root config
+        if filename == "checkpoints/000010/pretrained_model/train_config.json":
+            return str(cfg_file)
+        raise AssertionError(f"unexpected filename {filename}")
+
+    monkeypatch.setattr(tc, "hf_hub_download", fake_hf_hub_download)
+    monkeypatch.setattr(
+        tc, "find_latest_hub_checkpoint", lambda repo_id, token=None, revision=None: "checkpoints/000010"
+    )
+
+    loaded = TrainPipelineConfig.from_pretrained("user/interrupted-run")
+    assert loaded.dataset.repo_id == "u/d"
+    # Tried the root config first, then fell back to the latest checkpoint's config.
+    assert calls == ["train_config.json", "checkpoints/000010/pretrained_model/train_config.json"]
+
+
+def test_from_pretrained_raises_when_no_root_config_and_no_checkpoints(monkeypatch):
+    """No root config AND no checkpoints → a clear FileNotFoundError, not the raw HTTP error."""
+
+    def fake_hf_hub_download(filename=None, **kwargs):
+        raise _FakeHTTPError()
+
+    monkeypatch.setattr(tc, "hf_hub_download", fake_hf_hub_download)
+    monkeypatch.setattr(tc, "find_latest_hub_checkpoint", lambda repo_id, token=None, revision=None: None)
+
+    with pytest.raises(FileNotFoundError, match="train_config.json not found"):
+        TrainPipelineConfig.from_pretrained("user/empty-repo")