Fixed #29227 -- Allowed BooleanField to be null=True.

Thanks Lynn Cyrin for contributing to the patch, and Nick Pope for review.

2 files changed, 15 insertions, 1 deletions

diff --git a/tests/expressions_case/models.py b/tests/expressions_case/models.py
index 7c1a8d75b7..570b8c1849 100644
--- a/tests/expressions_case/models.py
+++ b/tests/expressions_case/models.py
@@ -25,7 +25,8 @@ class CaseTestModel(models.Model):
     if Image:
         image = models.ImageField(null=True)
     generic_ip_address = models.GenericIPAddressField(null=True)
-    null_boolean = models.NullBooleanField()
+    null_boolean = models.BooleanField(null=True)
+    null_boolean_old = models.NullBooleanField()
     positive_integer = models.PositiveIntegerField(null=True)
     positive_small_integer = models.PositiveSmallIntegerField(null=True)
     slug = models.SlugField(default='')
diff --git a/tests/expressions_case/tests.py b/tests/expressions_case/tests.py
index a688dc073d..94731491e0 100644
--- a/tests/expressions_case/tests.py
+++ b/tests/expressions_case/tests.py
@@ -820,6 +820,19 @@ class CaseExpressionTests(TestCase):
             transform=attrgetter('integer', 'null_boolean')
         )
 
+    def test_update_null_boolean_old(self):
+        CaseTestModel.objects.update(
+            null_boolean_old=Case(
+                When(integer=1, then=True),
+                When(integer=2, then=False),
+            ),
+        )
+        self.assertQuerysetEqual(
+            CaseTestModel.objects.all().order_by('pk'),
+            [(1, True), (2, False), (3, None), (2, False), (3, None), (3, None), (4, None)],
+            transform=attrgetter('integer', 'null_boolean_old')
+        )
+
     def test_update_positive_integer(self):
         CaseTestModel.objects.update(
             positive_integer=Case(