Enable SocketCAN interface tests in GitHub CI (#1484)

* Update CI to set up vcan and run SocketCAN tests

* Add test to document PyPy raw CAN socket implementation status

* Update test for restarting of SocketCAN SendTask

Previously, it was not permitted to restart an already started period
send task for SocketCAN. This behavior was changed in PR #1440. This
commit adjusts the test to reflect this change.

* Update PyPy raw CAN socket test failure into warning

Author: lumagi

.github/workflows/ci.yml

@@ -38,10 +38,18 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install tox
+    - name: Setup SocketCAN
+      if: ${{ matrix.os == 'ubuntu-latest' }}
+      run: |
+        sudo apt-get -y install linux-modules-extra-$(uname -r)
+        sudo ./test/open_vcan.sh
     - name: Test with pytest via tox
       run: |
         tox -e gh
-
+      env:
+        # SocketCAN tests currently fail with PyPy because it does not support raw CAN sockets
+        # See: https://foss.heptapod.net/pypy/pypy/-/issues/3809
+        TEST_SOCKETCAN: "${{ matrix.os == 'ubuntu-latest' && ! startsWith(matrix.python-version, 'pypy' ) }}"
     - name: Coveralls Parallel
       uses: coverallsapp/github-action@master
       with:

test/test_cyclic_socketcan.py

@@ -256,14 +256,8 @@ def test_start_already_started_task(self):
         task_a = self._send_bus.send_periodic(messages_a, self.PERIOD)
         time.sleep(0.1)
 
-        # Try to start it again, task_id is not incremented in this case
-        with self.assertRaises(can.CanOperationError) as ctx:
-            task_a.start()
-        self.assertEqual(
-            "A periodic task for task ID 1 is already in progress by the SocketCAN Linux layer",
-            str(ctx.exception),
-        )
-
+        # Task restarting is permitted as of #1440
+        task_a.start()
         task_a.stop()
 
     def test_create_same_id(self):

test/test_socketcan.py

@@ -6,8 +6,17 @@
 import ctypes
 import struct
 import unittest
+import warnings
 from unittest.mock import patch
+import can
 
+from can.interfaces.socketcan.constants import (
+    CAN_BCM_TX_DELETE,
+    CAN_BCM_TX_SETUP,
+    SETTIMER,
+    STARTTIMER,
+    TX_COUNTEVT,
+)
 from can.interfaces.socketcan.socketcan import (
     bcm_header_factory,
     build_bcm_header,
@@ -16,13 +25,7 @@
     build_bcm_update_header,
     BcmMsgHead,
 )
-from can.interfaces.socketcan.constants import (
-    CAN_BCM_TX_DELETE,
-    CAN_BCM_TX_SETUP,
-    SETTIMER,
-    STARTTIMER,
-    TX_COUNTEVT,
-)
+from .config import IS_LINUX, IS_PYPY
 
 
 class SocketCANTest(unittest.TestCase):
@@ -353,6 +356,24 @@ def test_build_bcm_update_header(self):
         self.assertEqual(can_id, result.can_id)
         self.assertEqual(1, result.nframes)
 
+    @unittest.skipUnless(IS_LINUX and IS_PYPY, "Only test when run on Linux with PyPy")
+    def test_pypy_socketcan_support(self):
+        """Wait for PyPy raw CAN socket support
+
+        This test shall document raw CAN socket support under PyPy. Once this test fails, it is likely that PyPy
+        either implemented raw CAN socket support or at least changed the error that is thrown.
+        https://foss.heptapod.net/pypy/pypy/-/issues/3809
+        https://github.com/hardbyte/python-can/issues/1479
+        """
+        try:
+            can.Bus(interface="socketcan", channel="vcan0", bitrate=500000)
+        except OSError as e:
+            if "unknown address family" not in str(e):
+                warnings.warn(
+                    "Please check if PyPy has implemented raw CAN socket support! "
+                    "See: https://foss.heptapod.net/pypy/pypy/-/issues/3809"
+                )
+
 
 if __name__ == "__main__":
     unittest.main()

tox.ini

@@ -26,6 +26,7 @@ passenv =
     GITHUB_*
     COVERALLS_*
     PY_COLORS
+    TEST_SOCKETCAN
 
 [testenv:travis]
 passenv =