diff --git a/tests/testutil.py b/tests/testutil.py
index 8dd7e1b8687d07cffc866d428d2a13e94ccb7830..9963f75ed7d5fe5fde361683b6cdce7ff42defe7 100644
--- a/tests/testutil.py
+++ b/tests/testutil.py
@@ -77,6 +77,18 @@ def Posting(account, number,
         meta,
     )
 
+LINK_METADATA_STRINGS = {
+    'Invoices/304321.pdf',
+    'rt:123/456',
+    'rt://ticket/234',
+}
+
+NON_LINK_METADATA_STRINGS = {
+    '',
+    ' ',
+    '     ',
+}
+
 NON_STRING_METADATA_VALUES = [
     Decimal(5),
     FY_MID_DATE,