Add typing and cover CI test failure

Author: MattWoodhead

can/interfaces/ixxat/canlib.py

@@ -1,4 +1,4 @@
-from typing import Callable, Optional, Sequence, Union
+from typing import Callable, Optional, Sequence, Union, List
 
 import can.interfaces.ixxat.canlib_vcinpl as vcinpl
 import can.interfaces.ixxat.canlib_vcinpl2 as vcinpl2
@@ -8,6 +8,7 @@
     CyclicSendTaskABC,
     Message,
 )
+from can.typechecking import AutoDetectedConfig
 
 
 class IXXATBus(BusABC):
@@ -170,5 +171,5 @@ def state(self) -> BusState:
         return self.bus.state
 
     @staticmethod
-    def _detect_available_configs():
+    def _detect_available_configs() -> List[AutoDetectedConfig]:
         return vcinpl._detect_available_configs()

can/interfaces/ixxat/canlib_vcinpl.py

@@ -14,7 +14,7 @@
 import logging
 import sys
 import warnings
-from typing import Callable, Optional, Sequence, Tuple, Union
+from typing import Callable, Optional, Sequence, Tuple, Union, List
 
 from can import (
     BusABC,
@@ -29,6 +29,7 @@
 from can.ctypesutil import HRESULT as ctypes_HRESULT
 from can.exceptions import CanInitializationError, CanInterfaceNotImplementedError
 from can.util import deprecated_args_alias
+from can.typechecking import AutoDetectedConfig
 
 from . import constants, structures
 from .exceptions import *
@@ -944,7 +945,7 @@ def get_ixxat_hwids():
     return hwids
 
 
-def _detect_available_configs():
+def _detect_available_configs() -> List[AutoDetectedConfig]:
 
     config_list = []  # list in wich to store the resulting bus kwargs
 
@@ -956,33 +957,36 @@ def _detect_available_configs():
     channel_handle = HANDLE()
     device_handle2 = HANDLE()
 
-    _canlib.vciEnumDeviceOpen(ctypes.byref(device_handle))
-    while True:
-        try:
-            _canlib.vciEnumDeviceNext(device_handle, ctypes.byref(device_info))
-        except StopIteration:
-            break
-        else:
-            hwid = device_info.UniqueHardwareId.AsChar.decode("ascii")
-            _canlib.vciDeviceOpen(
-                ctypes.byref(device_info.VciObjectId),
-                ctypes.byref(device_handle2),
-            )
-            for channel in range(4):
-                try:
-                    _canlib.canChannelOpen(
-                        device_handle2,
-                        channel,
-                        constants.FALSE,
-                        ctypes.byref(channel_handle),
-                    )
-                except Exception:
-                    # Array outside of bounds error == accessing a channel not in the hardware
-                    break
-                else:
-                    _canlib.canChannelClose(channel_handle)
-                    config_list.append({"interface": "ixxat", "channel": channel, "unique_hardware_id": hwid})
-            _canlib.vciDeviceClose(device_handle2)
-    _canlib.vciEnumDeviceClose(device_handle)
+    try:
+        _canlib.vciEnumDeviceOpen(ctypes.byref(device_handle))
+        while True:
+            try:
+                _canlib.vciEnumDeviceNext(device_handle, ctypes.byref(device_info))
+            except StopIteration:
+                break
+            else:
+                hwid = device_info.UniqueHardwareId.AsChar.decode("ascii")
+                _canlib.vciDeviceOpen(
+                    ctypes.byref(device_info.VciObjectId),
+                    ctypes.byref(device_handle2),
+                )
+                for channel in range(4):
+                    try:
+                        _canlib.canChannelOpen(
+                            device_handle2,
+                            channel,
+                            constants.FALSE,
+                            ctypes.byref(channel_handle),
+                        )
+                    except Exception:
+                        # Array outside of bounds error == accessing a channel not in the hardware
+                        break
+                    else:
+                        _canlib.canChannelClose(channel_handle)
+                        config_list.append({"interface": "ixxat", "channel": channel, "unique_hardware_id": hwid})
+                _canlib.vciDeviceClose(device_handle2)
+        _canlib.vciEnumDeviceClose(device_handle)
+    except AttributeError:
+        pass  # _canlib is None in the CI tests -> return a blank list
 
     return config_list