Add test to make sure policy dataclass configs match yaml configs (#292)

tests/test_policies.py

@@ -26,7 +26,11 @@ from lerobot.common.datasets.factory import make_dataset
 from lerobot.common.datasets.utils import cycle
 from lerobot.common.envs.factory import make_env
 from lerobot.common.envs.utils import preprocess_observation
-from lerobot.common.policies.factory import get_policy_and_config_classes, make_policy
+from lerobot.common.policies.factory import (
+    _policy_cfg_from_hydra_cfg,
+    get_policy_and_config_classes,
+    make_policy,
+)
 from lerobot.common.policies.normalize import Normalize, Unnormalize
 from lerobot.common.policies.policy_protocol import Policy
 from lerobot.common.utils.utils import init_hydra_config
@@ -210,6 +214,23 @@ def test_policy_defaults(policy_name: str):
     policy_cls()
 
 
+@pytest.mark.parametrize(
+    "env_name,policy_name",
+    [
+        ("xarm", "tdmpc"),
+        ("pusht", "diffusion"),
+        ("aloha", "act"),
+    ],
+)
+def test_yaml_matches_dataclass(env_name: str, policy_name: str):
+    """Check that dataclass configs match their respective yaml configs."""
+    hydra_cfg = init_hydra_config(DEFAULT_CONFIG_PATH, overrides=[f"env={env_name}", f"policy={policy_name}"])
+    _, policy_cfg_cls = get_policy_and_config_classes(policy_name)
+    policy_cfg_from_hydra = _policy_cfg_from_hydra_cfg(policy_cfg_cls, hydra_cfg)
+    policy_cfg_from_dataclass = policy_cfg_cls()
+    assert policy_cfg_from_hydra == policy_cfg_from_dataclass
+
+
 @pytest.mark.parametrize("policy_name", available_policies)
 def test_save_and_load_pretrained(policy_name: str):
     policy_cls, _ = get_policy_and_config_classes(policy_name)
@@ -318,7 +339,10 @@ def test_normalize(insert_temporal_dim):
 @pytest.mark.parametrize(
     "env_name, policy_name, extra_overrides, file_name_extra",
     [
-        ("xarm", "tdmpc", [], ""),
+        # TODO(alexander-soare): `policy.use_mpc=false` was previously the default in the config yaml but it
+        # was changed to true. For some reason, tests would pass locally, but not in CI. So here we override
+        # to test with `policy.use_mpc=false`.
+        ("xarm", "tdmpc", ["policy.use_mpc=false"], ""),
         (
             "pusht",
             "diffusion",
@@ -342,7 +366,8 @@ def test_backward_compatibility(env_name, policy_name, extra_overrides, file_nam
            include a report on what changed and how that affected the outputs.
         2. Go to the `if __name__ == "__main__"` block of `tests/scripts/save_policy_to_safetensors.py` and
            add the policies you want to update the test artifacts for.
-        3. Run `python tests/scripts/save_policy_to_safetensors.py`. The test artifact should be updated.
+        3. Run `DATA_DIR=tests/data python tests/scripts/save_policy_to_safetensors.py`. The test artifact
+           should be updated.
         4. Check that this test now passes.
         5. Remember to restore `tests/scripts/save_policy_to_safetensors.py` to its original state.
         6. Remember to stage and commit the resulting changes to `tests/data`.