diff --git a/tests/test_string_management.py b/tests/test_string_management.py
index be1e83f..aa0a4fc 100644
--- a/tests/test_string_management.py
+++ b/tests/test_string_management.py
@@ -67,6 +67,7 @@ def test_strip_encapsulated(s, encaps, expected):
     # Expected nones
     ('NaN', None),
     ('NONE', None),
+    (-9999, None),  # integer case
     ('-9999', None),
     ('-9999.0', None),
     (-9999.0, None),