proxmox_subnet: add unit tests and fix doc

Author: JanaHoch

plugins/modules/proxmox_subnet.py

@@ -33,6 +33,16 @@
       - If O(state=present) then it will update the subnet if needed.
     type: bool
     default: True
+  dhcp_range_update_mode:
+    description:
+      - Only applicable for O(state=present) and it will honor and only make changes when O(update=true)
+      - If set to append and new dhcp_range passed it will just append to existing ranges.
+      - And If no dhcp_range passed and there are existing ranges it will just ignore existing ranges and only update other params if needed
+      - If set to overwrite and new dhcp_range passed it will overwrite existing ranges.
+      - If no dhcp_range passed and there are existing ranges it will delete all dhcp_ranges
+    type: str
+    default: append
+    choices: ['append', 'overwrite']
   subnet:
     description:
       - subnet CIDR.
@@ -190,10 +200,12 @@ def get_ansible_module():
 def get_dhcp_range(dhcp_range=None):
     if not dhcp_range:
         return None
+
     def extract(item):
         start = item.get('start-address') or item.get('start')
         end = item.get('end-address') or item.get('end')
         return f"start-address={start},end-address={end}"
+
     return [extract(x) for x in dhcp_range]
 
 
@@ -267,7 +279,7 @@ def update_subnet(self, **subnet_params):
         existing_subnets = self.get_subnets(vnet_name)
 
         # Check for subnet params other than dhcp-range
-        _, subnet_update = compare_list_of_dicts(
+        x, subnet_update = compare_list_of_dicts(
             existing_list=existing_subnets,
             new_list=[new_subnet],
             uid='id',
@@ -291,7 +303,7 @@ def update_subnet(self, **subnet_params):
             if dhcp_range_update_mode == 'append':
                 if partial_overlap:
                     self.module.fail_json(
-                        msg=f"There are partially overlapping DHCP ranges. this is not allowed."
+                        msg="There are partially overlapping DHCP ranges. this is not allowed."
                     )
 
                 if len(new_dhcp) > 0:

tests/unit/plugins/modules/test_proxmox_subnet.py

@@ -0,0 +1,169 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (c) 2025, Jana Hoch <[email protected]>
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+from __future__ import absolute_import, division, print_function
+
+__metaclass__ = type
+
+from unittest.mock import patch, Mock
+
+import pytest
+
+proxmoxer = pytest.importorskip("proxmoxer")
+
+from ansible_collections.community.proxmox.plugins.modules import proxmox_subnet
+from ansible_collections.community.internal_test_tools.tests.unit.plugins.modules.utils import (
+    ModuleTestCase,
+    set_module_args,
+)
+import ansible_collections.community.proxmox.plugins.module_utils.proxmox as proxmox_utils
+
+RAW_SUBNETS = [
+    {
+        "type": "subnet",
+        "subnet": "ans1-10.10.2.0-24",
+        "zone": "ans1",
+        "snat": 0,
+        "cidr": "10.10.2.0/24",
+        "id": "ans1-10.10.2.0-24",
+        "mask": "24",
+        "dhcp-range": [
+            {
+                "start-address": "10.10.2.5",
+                "end-address": "10.10.2.25"
+            },
+            {
+                "start-address": "10.10.2.50",
+                "end-address": "10.10.2.100"
+            }
+        ],
+        "digest": "c870dc42a3b5356b6037590e9552cbd5d2334963",
+        "vnet": "test",
+        "network": "10.10.2.0"
+    }
+]
+
+
+def exit_json(*args, **kwargs):
+    """function to patch over exit_json; package return data into an exception"""
+    if 'changed' not in kwargs:
+        kwargs['changed'] = False
+    raise SystemExit(kwargs)
+
+
+def fail_json(*args, **kwargs):
+    """function to patch over fail_json; package return data into an exception"""
+    kwargs['failed'] = True
+    raise SystemExit(kwargs)
+
+
+def get_module_args(vnet, subnet, zone, state='present', dhcp_range=None, snat=0, dhcp_range_update_mode='append'):
+    return {
+        'api_host': 'host',
+        'api_user': 'user',
+        'api_password': 'password',
+        'vnet': vnet,
+        'subnet': subnet,
+        'zone': zone,
+        'state': state,
+        'dhcp_range': dhcp_range,
+        'snat': snat,
+        'dhcp_range_update_mode': dhcp_range_update_mode
+    }
+
+
+class TestProxmoxSubnetModule(ModuleTestCase):
+    def setUp(self):
+        super(TestProxmoxSubnetModule, self).setUp()
+        proxmox_utils.HAS_PROXMOXER = True
+        self.module = proxmox_subnet
+        self.fail_json_patcher = patch('ansible.module_utils.basic.AnsibleModule.fail_json',
+                                       new=Mock(side_effect=fail_json))
+        self.exit_json_patcher = patch('ansible.module_utils.basic.AnsibleModule.exit_json', new=exit_json)
+
+        self.fail_json_mock = self.fail_json_patcher.start()
+        self.exit_json_patcher.start()
+        self.connect_mock = patch(
+            "ansible_collections.community.proxmox.plugins.module_utils.proxmox.ProxmoxAnsible._connect",
+        ).start()
+        self.connect_mock.return_value.cluster.return_value.sdn.return_value.vnets.return_value.subnets.return_value.get.return_value = RAW_SUBNETS
+
+    def tearDown(self):
+        self.connect_mock.stop()
+        self.exit_json_patcher.stop()
+        self.fail_json_patcher.stop()
+        super(TestProxmoxSubnetModule, self).tearDown()
+
+    def test_subnet_create(self):
+        # Create new Zone
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='new_vnet',
+                                                 subnet='10.10.10.0/24',
+                                                 zone='test_zone')):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert result["changed"] is True
+        assert result["msg"] == "Created new subnet 10.10.10.0/24"
+        assert result['subnet'] == 'test_zone-10.10.10.0-24'
+
+    def test_subnet_update(self):
+        # Normal subnet param (snat) differ
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='test',
+                                                 subnet='10.10.2.0/24',
+                                                 zone='ans1',
+                                                 snat=1)):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert result["changed"] is True
+        assert result["msg"] == "Updated subnet ans1-10.10.2.0-24"
+        assert result['subnet'] == 'ans1-10.10.2.0-24'
+
+        # No update needed
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='test',
+                                                 subnet='10.10.2.0/24',
+                                                 zone='ans1')):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert result["changed"] is False
+        assert result["msg"] == "subnet ans1-10.10.2.0-24 is already present with correct parameters."
+        assert result['subnet'] == 'ans1-10.10.2.0-24'
+
+        # New dhcp_range
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='test',
+                                                 subnet='10.10.2.0/24',
+                                                 zone='ans1',
+                                                 dhcp_range=[{'start': '10.10.2.150', 'end': '10.10.2.200'}])):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert result["changed"] is True
+        assert result["msg"] == "Updated subnet ans1-10.10.2.0-24"
+        assert result['subnet'] == 'ans1-10.10.2.0-24'
+
+        # dhcp_range is partially overlapping and mode is append
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='test',
+                                                 subnet='10.10.2.0/24',
+                                                 zone='ans1',
+                                                 dhcp_range=[{'start': '10.10.2.10', 'end': '10.10.2.20'}])):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert self.fail_json_mock.called
+        assert result["failed"] is True
+        assert result["msg"] == "There are partially overlapping DHCP ranges. this is not allowed."
+
+    def test_subnet_absent(self):
+        with pytest.raises(SystemExit) as exc_info:
+            with set_module_args(get_module_args(vnet='test',
+                                                 subnet='10.10.2.0/24',
+                                                 zone='ans1', state='absent')):
+                self.module.main()
+        result = exc_info.value.args[0]
+        assert result["changed"] is True
+        assert result["msg"] == "Deleted subnet ans1-10.10.2.0-24"
+        assert result['subnet'] == 'ans1-10.10.2.0-24'