Convert BusState to enum when read with configparser (#1957)

* Convert BusState to enum when read with configparser (#1956)

* Move BusState conversion to util.py (#1956)

* Check state argument type before attempting conversion (#1956)

* Add tests (#1956)

* Fix formatting (#1956)

* Compare enums by identity (#1956)

---------

Co-authored-by: Greg Brooks <[email protected]>

Author: Gregox273

can/util.py

@@ -249,6 +249,12 @@ def _create_bus_config(config: dict[str, Any]) -> typechecking.BusConfig:
     if "fd" in config:
         config["fd"] = config["fd"] not in (0, False)
 
+    if "state" in config and not isinstance(config["state"], can.BusState):
+        try:
+            config["state"] = can.BusState[config["state"]]
+        except KeyError as e:
+            raise ValueError("State config not valid!") from e
+
     return cast("typechecking.BusConfig", config)
 
 

doc/interfaces/pcan.rst

@@ -15,7 +15,7 @@ Here is an example configuration file for using `PCAN-USB <https://www.peak-syst
     [default]
     interface = pcan
     channel = PCAN_USBBUS1
-    state = can.bus.BusState.PASSIVE
+    state = PASSIVE
     bitrate = 500000
 
 ``channel`` (default ``"PCAN_USBBUS1"``)

test/test_util.py

@@ -209,6 +209,29 @@ def test_bit_timing_fd_cfg(self):
         assert timing.data_tseg2 == 10
         assert timing.data_sjw == 10
 
+    def test_state_with_str(self):
+        can_cfg = _create_bus_config(
+            {
+                **self.base_config,
+                "state": "PASSIVE",
+            }
+        )
+        state = can_cfg["state"]
+        assert isinstance(state, can.BusState)
+        assert state is can.BusState.PASSIVE
+
+    def test_state_with_enum(self):
+        expected_state = can.BusState.PASSIVE
+        can_cfg = _create_bus_config(
+            {
+                **self.base_config,
+                "state": expected_state,
+            }
+        )
+        state = can_cfg["state"]
+        assert isinstance(state, can.BusState)
+        assert state is expected_state
+
 
 class TestChannel2Int(unittest.TestCase):
     def test_channel2int(self) -> None: