test: use dynamic ports and add coverage in feature_bind_port_discover

diff --git a/test/functional/feature_bind_port_discover.py b/test/functional/feature_bind_port_discover.py
index f3fe3454..613b111b 100755
--- a/test/functional/feature_bind_port_discover.py
+++ b/test/functional/feature_bind_port_discover.py
@@ -10,31 +10,46 @@ from test_framework.test_framework import BitcoinTestFramework, SkipTest
 from test_framework.util import (
     assert_equal,
     assert_not_equal,
+    p2p_port,
+    tor_port,
 )
 
-# We need to bind to a routable address for this test to exercise the relevant code
-# and also must have another routable address on another interface which must not
-# be named "lo" or "lo0".
-# To set these routable addresses on the machine, use:
+# We need to bind to routable addresses for this test. Both addresses must be on an
+# interface that is UP and not a loopback interface (IFF_LOOPBACK). To set these
+# routable addresses on the machine, use:
 # Linux:
-# ifconfig lo:0 1.1.1.1/32 up && ifconfig lo:1 2.2.2.2/32 up  # to set up
-# ifconfig lo:0 down && ifconfig lo:1 down  # to remove it, after the test
+# First find your interfaces: ip addr show
+# Then use your actual interface names (replace INTERFACE_NAME with yours):
+# ip addr add 1.1.1.1/32 dev INTERFACE_NAME && ip addr add 2.2.2.2/32 dev INTERFACE_NAME  # to set up
+# ip addr del 1.1.1.1/32 dev INTERFACE_NAME && ip addr del 2.2.2.2/32 dev INTERFACE_NAME  # to remove it
+#
+# macOS:
+# ifconfig en0 alias 1.1.1.1 && ifconfig en0 alias 2.2.2.2  # to set up
+# ifconfig en0 1.1.1.1 -alias && ifconfig en0 2.2.2.2 -alias  # to remove it, after the test
+#
 # FreeBSD:
 # ifconfig em0 1.1.1.1/32 alias && ifconfig wlan0 2.2.2.2/32 alias  # to set up
 # ifconfig em0 1.1.1.1 -alias && ifconfig wlan0 2.2.2.2 -alias  # to remove it, after the test
 ADDR1 = '1.1.1.1'
 ADDR2 = '2.2.2.2'
 
-BIND_PORT = 31001
-
 class BindPortDiscoverTest(BitcoinTestFramework):
     def set_test_params(self):
         # Avoid any -bind= on the command line. Force the framework to avoid adding -bind=127.0.0.1.
-        self.setup_clean_chain = True
         self.bind_to_localhost_only = False
+        # Get dynamic ports for each node from the test framework
+        self.bind_ports = [
+            p2p_port(0),
+            p2p_port(2), # node0 will use their port + 1 for onion listen, which is the same as p2p_port(1), so avoid collision
+            p2p_port(3),
+            p2p_port(4),
+        ]
         self.extra_args = [
-            ['-discover', f'-port={BIND_PORT}'], # bind on any
-            ['-discover', f'-bind={ADDR1}:{BIND_PORT}'],
+            ['-discover', f'-port={self.bind_ports[0]}', '-listen=1'], # Without any -bind
+            ['-discover', f'-bind=0.0.0.0:{self.bind_ports[1]}'], # Explicit -bind=0.0.0.0
+            # Explicit -whitebind=0.0.0.0, add onion bind to avoid port conflict
+            ['-discover', f'-whitebind=0.0.0.0:{self.bind_ports[2]}', f'-bind=127.0.0.1:{tor_port(3)}=onion'],
+            ['-discover', f'-bind={ADDR1}:{self.bind_ports[3]}'], # Explicit -bind=routable_addr
         ]
         self.num_nodes = len(self.extra_args)
 
@@ -70,28 +85,35 @@ class BindPortDiscoverTest(BitcoinTestFramework):
 
     def run_test(self):
         self.log.info(
-                "Test that if -bind= is not passed then all addresses are "
+                "Test that if -bind= is not passed or -bind=0.0.0.0 is used then all addresses are "
                 "added to localaddresses")
-        found_addr1 = False
-        found_addr2 = False
-        for local in self.nodes[0].getnetworkinfo()['localaddresses']:
-            if local['address'] == ADDR1:
-                found_addr1 = True
-                assert_equal(local['port'], BIND_PORT)
-            if local['address'] == ADDR2:
-                found_addr2 = True
-                assert_equal(local['port'], BIND_PORT)
-        assert found_addr1
-        assert found_addr2
+        for i in [0, 1, 2]:
+            found_addr1 = False
+            found_addr2 = False
+            localaddresses = self.nodes[i].getnetworkinfo()['localaddresses']
+            for local in localaddresses:
+                if local['address'] == ADDR1:
+                    found_addr1 = True
+                    assert_equal(local['port'], self.bind_ports[i])
+                if local['address'] == ADDR2:
+                    found_addr2 = True
+                    assert_equal(local['port'], self.bind_ports[i])
+            if not found_addr1:
+                self.log.error(f"Address {ADDR1} not found in node{i}'s local addresses: {localaddresses}")
+                assert False
+            if not found_addr2:
+                self.log.error(f"Address {ADDR2} not found in node{i}'s local addresses: {localaddresses}")
+                assert False
 
         self.log.info(
-                "Test that if -bind= is passed then only that address is "
+                "Test that if -bind=routable_addr is passed then only that address is "
                 "added to localaddresses")
         found_addr1 = False
-        for local in self.nodes[1].getnetworkinfo()['localaddresses']:
+        i = 3
+        for local in self.nodes[i].getnetworkinfo()['localaddresses']:
             if local['address'] == ADDR1:
                 found_addr1 = True
-                assert_equal(local['port'], BIND_PORT)
+                assert_equal(local['port'], self.bind_ports[i])
             assert_not_equal(local['address'], ADDR2)
         assert found_addr1