nmcli: fix empty list to replace / remove values (#6769)

changelogs/fragments/6769-nmcli-fix-empty-list.yml

@@ -0,0 +1,2 @@
+ bugfixes:
+  - nmcli - fix support for empty list (in compare and scrape) (https://github.com/ansible-collections/community.general/pull/6769).

plugins/modules/nmcli.py

@@ -2183,7 +2183,10 @@ class Nmcli(object):
             if key and len(pair) > 1:
                 raw_value = pair[1].lstrip()
                 if raw_value == '--':
-                    conn_info[key] = None
+                    if key_type == list:
+                        conn_info[key] = []
+                    else:
+                        conn_info[key] = None
                 elif key == 'bond.options':
                     # Aliases such as 'miimon', 'downdelay' are equivalent to the +bond.options 'option=value' syntax.
                     opts = raw_value.split(',')
@@ -2270,7 +2273,7 @@ class Nmcli(object):
             # We can't just do `if not value` because then if there's a value
             # of 0 specified as an integer it'll be interpreted as empty when
             # it actually isn't.
-            if value != 0 and not value:
+            if value not in (0, []) and not value:
                 continue
 
             if key in conn_info:

tests/unit/plugins/modules/test_nmcli.py

@@ -262,6 +262,25 @@ ipv4.routes:                            { ip = 192.168.200.0/24, nh = 192.168.1.
 ipv4.route-metric:                      10
 """
 
+TESTCASE_ETHERNET_MOD_IPV4_INT_WITH_ROUTE_AND_METRIC_CLEAR = [
+    {
+        'type': 'ethernet',
+        'conn_name': 'non_existent_nw_device',
+        'routes4': [],
+        'state': 'present',
+        '_ansible_check_mode': False,
+        '_ansible_diff': True,
+    },
+    {
+        'type': 'ethernet',
+        'conn_name': 'non_existent_nw_device',
+        'routes4_extended': [],
+        'state': 'present',
+        '_ansible_check_mode': False,
+        '_ansible_diff': True,
+    },
+]
+
 TESTCASE_ETHERNET_MOD_IPV6_INT_WITH_ROUTE_AND_METRIC = [
     {
         'type': 'ethernet',
@@ -1672,6 +1691,17 @@ def mocked_ethernet_connection_with_ipv4_static_address_static_route_metric_modi
                ))
 
 
+@pytest.fixture
+def mocked_ethernet_connection_with_ipv4_static_address_static_route_metric_clear(mocker):
+    mocker_set(mocker,
+               connection_exists=True,
+               execute_return=None,
+               execute_side_effect=(
+                   (0, TESTCASE_ETHERNET_MOD_IPV4_INT_WITH_ROUTE_AND_METRIC_SHOW_OUTPUT, ""),
+                   (0, "", ""),
+               ))
+
+
 @pytest.fixture
 def mocked_ethernet_connection_with_ipv6_static_address_static_route_metric_modify(mocker):
     mocker_set(mocker,
@@ -2992,6 +3022,38 @@ def test_ethernet_connection_static_ipv4_address_static_route_with_metric_modify
     assert not results.get('failed')
 
 
+@pytest.mark.parametrize('patch_ansible_module', TESTCASE_ETHERNET_MOD_IPV4_INT_WITH_ROUTE_AND_METRIC_CLEAR, indirect=['patch_ansible_module'])
+def test_ethernet_connection_static_ipv4_address_static_route_with_metric_clear(
+        mocked_ethernet_connection_with_ipv4_static_address_static_route_metric_clear, capfd):
+    """
+    Test : Modify ethernet connection with static IPv4 address and static route
+    """
+    with pytest.raises(SystemExit):
+        nmcli.main()
+
+    arg_list = nmcli.Nmcli.execute_command.call_args_list
+    add_args, add_kw = arg_list[1]
+
+    assert add_args[0][0] == '/usr/bin/nmcli'
+    assert add_args[0][1] == 'con'
+    assert add_args[0][2] == 'modify'
+    assert add_args[0][3] == 'non_existent_nw_device'
+
+    add_args_text = list(map(to_text, add_args[0]))
+
+    for param in ['ipv4.routes', '']:
+        assert param in add_args_text
+
+    out, err = capfd.readouterr()
+    results = json.loads(out)
+
+    assert 'ipv4.routes' in results['diff']['before']
+    assert 'ipv4.routes' in results['diff']['after']
+
+    assert results.get('changed') is True
+    assert not results.get('failed')
+
+
 @pytest.mark.parametrize('patch_ansible_module', TESTCASE_ETHERNET_ADD_IPV6_INT_WITH_ROUTE, indirect=['patch_ansible_module'])
 def test_ethernet_connection_static_ipv6_address_static_route_create(mocked_ethernet_connection_with_ipv6_static_address_static_route_create, capfd):
     """