1 files changed, 55 insertions, 0 deletions
diff --git a/tests/unit/test_module_utils_vyos.py b/tests/unit/test_module_utils_vyos.py
new file mode 100644
index 0000000..920e9a5
--- /dev/null
+++ b/tests/unit/test_module_utils_vyos.py
@@ -0,0 +1,55 @@
+# -*- coding: utf-8 -*-
+"""Unit tests for the shared functions in plugins/module_utils/vyos.py.
+
+Kept separate from any single module's test file since these tests
+shared, cross-module infrastructure (cast_by_spec, dict_op, autoclean,
+from_device) rather than any one module's own behavior -- a fix here
+should be verifiable, and shippable, independently of any module that
+happens to use it.
+"""
+from __future__ import absolute_import, division, print_function
+
+
+__metaclass__ = type
+
+import unittest
+
+from ansible_collections.vyos.rest.plugins.module_utils.vyos import cast_by_spec
+
+
+class TestCastBySpecIntCollapse(unittest.TestCase):
+    """Regression test for a confirmed defensive gap: cast_by_spec's
+    own docstring claims to handle VyOS's single-value collapse, and
+    the list branch already does, but the int branch previously called
+    int() directly with no such guard -- a genuinely collapsed list
+    for an int-typed leaf would have raised TypeError rather than
+    being handled. No module's own fields are known to hit this case
+    in live device output today (confirmed for vyos_static_routes:
+    distance/admin_distance are always plain scalars) -- this hardens
+    shared infrastructure against a case that could arise for a future
+    module's fields, matching what the docstring already promises.
+    """
+
+    def test_collapsed_single_value_list_for_int_field(self):
+        entry = {"distance": ["200"]}
+        cast_by_spec(entry, {"distance": {"type": "int"}})
+        self.assertEqual(entry["distance"], 200)
+
+    def test_plain_scalar_still_works(self):
+        entry = {"distance": "200"}
+        cast_by_spec(entry, {"distance": {"type": "int"}})
+        self.assertEqual(entry["distance"], 200)
+
+    def test_empty_list_becomes_none(self):
+        entry = {"distance": []}
+        cast_by_spec(entry, {"distance": {"type": "int"}})
+        self.assertIsNone(entry["distance"])
+
+    def test_none_value_untouched(self):
+        entry = {"distance": None}
+        cast_by_spec(entry, {"distance": {"type": "int"}})
+        self.assertIsNone(entry["distance"])
+
+
+if __name__ == "__main__":
+    unittest.main()