Fixed #29500 -- Fixed SQLite function crashes on null values.

Co-authored-by: Srinivas Reddy Thatiparthy <thatiparthysreenivas@gmail.com>
Co-authored-by: Nick Pope <nick.pope@flightdataservices.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/backends/sqlite/tests.py b/tests/backends/sqlite/tests.py
index c82ed1667d..86723a72d2 100644
--- a/tests/backends/sqlite/tests.py
+++ b/tests/backends/sqlite/tests.py
@@ -59,6 +59,22 @@ class Tests(TestCase):
         creation = DatabaseWrapper(settings_dict).creation
         self.assertEqual(creation._get_test_db_name(), creation.connection.settings_dict['TEST']['NAME'])
 
+    def test_regexp_function(self):
+        tests = (
+            ('test', r'[0-9]+', False),
+            ('test', r'[a-z]+', True),
+            ('test', None, None),
+            (None, r'[a-z]+', None),
+            (None, None, None),
+        )
+        for string, pattern, expected in tests:
+            with self.subTest((string, pattern)):
+                with connection.cursor() as cursor:
+                    cursor.execute('SELECT %s REGEXP %s', [string, pattern])
+                    value = cursor.fetchone()[0]
+                value = bool(value) if value in {0, 1} else value
+                self.assertIs(value, expected)
+
 
 @unittest.skipUnless(connection.vendor == 'sqlite', 'SQLite tests')
 @isolate_apps('backends')