Fix test

tests/robots/test_so100_follower.py

@@ -8,8 +8,6 @@ from lerobot.common.robots.so100_follower import (
     SO100FollowerConfig,
 )
 
-_MOTORS = SO100Follower(SO100FollowerConfig("")).bus.motors
-
 
 def _make_bus_mock() -> MagicMock:
     """Return a bus mock with just the attributes used by the robot."""
@@ -24,13 +22,6 @@ def _make_bus_mock() -> MagicMock:
 
     bus.connect.side_effect = _connect
     bus.disconnect.side_effect = _disconnect
-    bus.motors = _MOTORS
-    bus.is_calibrated = True
-    bus.sync_read.return_value = {m: i for i, m in enumerate(_MOTORS, 1)}
-    bus.sync_write.return_value = None
-    bus.write.return_value = None
-    bus.disable_torque.return_value = None
-    bus.enable_torque.return_value = None
 
     @contextmanager
     def _dummy_cm():
@@ -43,10 +34,24 @@ def _make_bus_mock() -> MagicMock:
 
 @pytest.fixture
 def follower():
+    bus_mock = _make_bus_mock()
+
+    def _bus_side_effect(*_args, **kwargs):
+        bus_mock.motors = kwargs["motors"]
+        motors_order: list[str] = list(bus_mock.motors)
+
+        bus_mock.sync_read.return_value = {motor: idx for idx, motor in enumerate(motors_order, 1)}
+        bus_mock.sync_write.return_value = None
+        bus_mock.write.return_value = None
+        bus_mock.disable_torque.return_value = None
+        bus_mock.enable_torque.return_value = None
+        bus_mock.is_calibrated = True
+        return bus_mock
+
     with (
         patch(
             "lerobot.common.robots.so100_follower.so100_follower.FeetechMotorsBus",
-            return_value=_make_bus_mock(),
+            side_effect=_bus_side_effect,
         ),
         patch.object(SO100Follower, "configure", lambda self: None),
     ):
@@ -71,20 +76,20 @@ def test_get_observation(follower):
     follower.connect()
     obs = follower.get_observation()
 
-    expected_keys = {f"{m}.pos" for m in _MOTORS}
+    expected_keys = {f"{m}.pos" for m in follower.bus.motors}
     assert set(obs.keys()) == expected_keys
 
-    for idx, motor in enumerate(_MOTORS, 1):
+    for idx, motor in enumerate(follower.bus.motors, 1):
         assert obs[f"{motor}.pos"] == idx
 
 
 def test_send_action(follower):
     follower.connect()
 
-    action = {f"{m}.pos": i * 10 for i, m in enumerate(_MOTORS, 1)}
+    action = {f"{m}.pos": i * 10 for i, m in enumerate(follower.bus.motors, 1)}
     returned = follower.send_action(action)
 
     assert returned == action
 
-    goal_pos = {m: (i + 1) * 10 for i, m in enumerate(_MOTORS)}
+    goal_pos = {m: (i + 1) * 10 for i, m in enumerate(follower.bus.motors)}
     follower.bus.sync_write.assert_called_once_with("Goal_Position", goal_pos)