[nexus] migrate test_radio_filter.py to nexus (#13010)

This commit migrates the functionality covered by
`tests/scripts/thread-cert/test_radio_filter.py` to a new Nexus test
`tests/nexus/test_radio_filter.cpp`.

The new test covers:
- Initial state of radio filter (disabled).
- Enabling radio filter on Router blocks pings.
- Disabling radio filter on Router restores pings.
- Enabling radio filter on SED causes it to detach.
- Disabling radio filter on SED allows it to reattach.

To make the test pass in Nexus, the following fixes were applied:
- Set external poll period to 40ms for SED to receive ping replies.
- Forced parent search on SED using `BecomeChild()` to avoid long
  backoff interval.

The energy scan portion of the original test is skipped because
`otPlatRadioEnergyScan` is not implemented in the Nexus platform.

The original Python test file is removed.

tests/scripts/thread-cert/test_radio_filter.py

@@ -1,151 +0,0 @@
-#!/usr/bin/env python3
-#
-#  Copyright (c) 2021, The OpenThread Authors.
-#  All rights reserved.
-#
-#  Redistribution and use in source and binary forms, with or without
-#  modification, are permitted provided that the following conditions are met:
-#  1. Redistributions of source code must retain the above copyright
-#     notice, this list of conditions and the following disclaimer.
-#  2. Redistributions in binary form must reproduce the above copyright
-#     notice, this list of conditions and the following disclaimer in the
-#     documentation and/or other materials provided with the distribution.
-#  3. Neither the name of the copyright holder nor the
-#     names of its contributors may be used to endorse or promote products
-#     derived from this software without specific prior written permission.
-#
-#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
-#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-#  POSSIBILITY OF SUCH DAMAGE.
-#
-
-import ipaddress
-import unittest
-
-import config
-import command
-import thread_cert
-
-# Test description:
-#
-# This test verifies the radio filter mechanism.
-#
-# Topology:
-#
-#   Leader -- Router
-#     |
-#     |
-#   Child
-#
-#
-
-LEADER = 1
-ROUTER = 2
-SED = 3
-
-WAIT_TIME = 5
-
-
-class RadioFilter(thread_cert.TestCase):
-    USE_MESSAGE_FACTORY = False
-    SUPPORT_NCP = False
-
-    TOPOLOGY = {
-        LEADER: {
-            'mode': 'rdn',
-            'allowlist': [ROUTER, SED]
-        },
-        ROUTER: {
-            'mode': 'rdn',
-            'allowlist': [LEADER]
-        },
-        SED: {
-            'is_mtd': True,
-            'mode': '-',
-            'timeout': config.DEFAULT_CHILD_TIMEOUT,
-            'allowlist': [LEADER]
-        },
-    }
-
-    def test(self):
-        leader = self.nodes[LEADER]
-        router = self.nodes[ROUTER]
-        sed = self.nodes[SED]
-
-        nodes = [leader, router, sed]
-
-        leader.start()
-        self.simulator.go(config.LEADER_STARTUP_DELAY)
-        self.assertEqual(leader.get_state(), 'leader')
-
-        router.start()
-        self.simulator.go(WAIT_TIME)
-        self.assertEqual(router.get_state(), 'router')
-
-        sed.start()
-        sed.set_pollperiod(40)
-        self.simulator.go(WAIT_TIME)
-        self.assertEqual(sed.get_state(), 'child')
-
-        # Validate initial state of `radiofilter` upon start
-        for node in nodes:
-            self.assertFalse(node.radiofilter_is_enabled())
-
-        leader_mleid = leader.get_mleid()
-        router_mleid = router.get_mleid()
-        sed_mleid = sed.get_mleid()
-
-        # Validate connections by pinging from leader, SED, and router
-        self.assertTrue(leader.ping(router_mleid))
-        self.assertTrue(sed.ping(leader_mleid))
-        self.assertTrue(router.ping(leader_mleid))
-
-        # Validate behavior when `radiofilter` is enabled on router
-        router.radiofilter_enable()
-        self.assertTrue(router.radiofilter_is_enabled())
-        self.assertFalse(leader.ping(router_mleid))
-        self.assertFalse(router.ping(leader_mleid))
-
-        # Validate behavior when `radiofilter` is disabled on router
-        router.radiofilter_disable()
-        self.assertFalse(router.radiofilter_is_enabled())
-        self.assertTrue(leader.ping(router_mleid))
-        self.assertTrue(router.ping(leader_mleid))
-
-        # Validate `radiofilter` behavior on sed.
-        self.assertTrue(sed.ping(leader_mleid))
-
-        sed.radiofilter_enable()
-        self.assertTrue(sed.radiofilter_is_enabled())
-        self.assertFalse(sed.ping(leader_mleid))
-
-        self.assertTrue(sed.radiofilter_is_enabled())
-        self.assertEqual(sed.get_state(), 'detached')
-
-        sed.radiofilter_disable()
-        self.assertFalse(sed.radiofilter_is_enabled())
-
-        self.simulator.go(WAIT_TIME)
-        self.assertEqual(sed.get_state(), 'child')
-        self.assertTrue(leader.ping(sed_mleid))
-        self.assertTrue(sed.ping(leader_mleid))
-
-        # Validate energy scan when `radiofilter` is enabled
-        scan_result = leader.scan_energy()
-        self.assertTrue(len(scan_result) > 0)
-        leader.radiofilter_enable()
-        self.assertTrue(leader.radiofilter_is_enabled())
-        scan_result = leader.scan_energy()
-        self.assertTrue(len(scan_result) == 0)
-
-
-if __name__ == '__main__':
-    unittest.main()