tests: refactor virtual interface tests

Split virtual interface tests in VPP into smaller and modular
tests for testing various interface types and features.

Type: test

Change-Id: Ic38af88379f75eee3090679d411edbdc8fd5d2e5
Signed-off-by: Naveen Joy <najoy@cisco.com>

test/test_vm_af_packet_l2.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+import unittest
+from framework import VppTestCase
+from vm_vpp_interfaces import (
+    TestSelector,
+    TestVPPInterfacesQemu,
+    generate_vpp_interface_tests,
+)
+from asfframework import VppTestRunner
+from vm_test_config import test_config
+
+
+class TestVPPInterfacesQemuAfPacketL2(TestVPPInterfacesQemu, VppTestCase):
+    """Test af_packet interfaces in L2 mode for IPv4/v6."""
+
+    # Set test_id(s) to run from vm_test_config
+    # The expansion of these numbers are included in the test docstring
+    tests_to_run = "12,20"
+
+    @classmethod
+    def setUpClass(cls):
+        super(TestVPPInterfacesQemuAfPacketL2, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(TestVPPInterfacesQemuAfPacketL2, cls).tearDownClass()
+
+    def tearDown(self):
+        super(TestVPPInterfacesQemuAfPacketL2, self).tearDown()
+
+
+SELECTED_TESTS = TestVPPInterfacesQemuAfPacketL2.tests_to_run
+tests = filter(TestSelector(SELECTED_TESTS).filter_tests, test_config["tests"])
+generate_vpp_interface_tests(tests, TestVPPInterfacesQemuAfPacketL2)
+
+if __name__ == "__main__":
+    unittest.main(testRunner=VppTestRunner)