Add test case

salt/modules/win_lgpo.py

@@ -4987,6 +4987,8 @@ def _load_policy_definitions(path='c:\\Windows\\PolicyDefinitions',
         if root == path:
             for t_admx_file in files:
                 admx_file_name, admx_file_ext = os.path.splitext(t_admx_file)
+                # Only process ADMX files, any other file will cause a
+                # stacktrace later on
                 if not admx_file_ext == '.admx':
                     log.debug('{0} is not an ADMX file'.format(t_admx_file))
                     continue
@@ -5005,9 +5007,6 @@ def _load_policy_definitions(path='c:\\Windows\\PolicyDefinitions',
                     namespaces['None'] = namespaces[None]
                     namespaces.pop(None)
                     namespace_string = 'None:'
-                this_prefix = xml_tree.xpath(
-                        '/{0}policyDefinitions/{0}policyNamespaces/{0}target/@prefix'.format(namespace_string),
-                        namespaces=namespaces)[0]
                 this_namespace = xml_tree.xpath(
                         '/{0}policyDefinitions/{0}policyNamespaces/{0}target/@namespace'.format(namespace_string),
                         namespaces=namespaces)[0]

tests/unit/modules/test_win_lgpo.py

@@ -5,6 +5,7 @@
 
 # Import Python Libs
 from __future__ import absolute_import, unicode_literals, print_function
+import glob
 import os
 
 # Import Salt Testing Libs
@@ -332,6 +333,38 @@ class WinLGPOGetPolicyADMXTestCase(TestCase, LoaderModuleMockMixin):
                             'Allow Telemetry': 'Not Configured'}}}}}
         self.assertDictEqual(result, expected)
 
+    def test__load_policy_definitions(self):
+        '''
+        Test that unexpected files in the PolicyDefinitions directory won't
+        cause the _load_policy_definitions function to explode
+        https://gitlab.com/saltstack/enterprise/lock/issues/3826
+        '''
+        # The PolicyDefinitions directory should only contain ADMX files. We
+        # want to make sure the `_load_policy_definitions` function skips non
+        # ADMX files in this directory.
+        # Create a bogus ADML file in PolicyDefinitions directory
+        bogus_fle = os.path.join(
+            'c:\\Windows\\PolicyDefinitions',
+            '_bogus.adml')
+        cache_dir = os.path.join(
+            win_lgpo.__opts__['cachedir'],
+            'lgpo',
+            'policy_defs')
+        try:
+            with open(bogus_fle, 'w+') as fh:
+                fh.write('<junk></junk>')
+            # This function doesn't return anything (None), it just loads
+            # the XPath structures into __context__. We're just making sure it
+            # doesn't stack trace here
+            self.assertIsNone(win_lgpo._load_policy_definitions())
+        finally:
+            # Remove source file
+            os.remove(bogus_fle)
+            # Remove cached file
+            search_string = '{0}\\_bogus*.adml'.format(cache_dir)
+            for file_name in glob.glob(search_string):
+                os.remove(file_name)
+
 
 @skipIf(not salt.utils.platform.is_windows(), 'System is not Windows')
 class WinLGPOGetPolicyFromPolicyInfoTestCase(TestCase, LoaderModuleMockMixin):