1 files changed, 36 insertions, 0 deletions
diff --git a/tests/model_forms/tests.py b/tests/model_forms/tests.py
index 8acc88b33f..f6e9a886a2 100644
--- a/tests/model_forms/tests.py
+++ b/tests/model_forms/tests.py
@@ -1802,3 +1802,39 @@ class M2mHelpTextTest(TestCase):
         html = form.as_p()
         self.assertInHTML('<ul id="id_status">', html)
         self.assertInHTML(dreaded_help_text, html, count=0)
+
+
+class ModelFormInheritanceTests(TestCase):
+    def test_form_subclass_inheritance(self):
+        class Form(forms.Form):
+            age = forms.IntegerField()
+
+        class ModelForm(forms.ModelForm, Form):
+            class Meta:
+                model = Writer
+                fields = '__all__'
+
+        self.assertEqual(list(ModelForm().fields.keys()), ['name', 'age'])
+
+    def test_field_shadowing(self):
+        class ModelForm(forms.ModelForm):
+            class Meta:
+                model = Writer
+                fields = '__all__'
+
+        class Mixin(object):
+            age = None
+
+        class Form(forms.Form):
+            age = forms.IntegerField()
+
+        class Form2(forms.Form):
+            foo = forms.IntegerField()
+
+        self.assertEqual(list(ModelForm().fields.keys()), ['name'])
+        self.assertEqual(list(type(str('NewForm'), (Mixin, Form), {})().fields.keys()), [])
+        self.assertEqual(list(type(str('NewForm'), (Form2, Mixin, Form), {})().fields.keys()), ['foo'])
+        self.assertEqual(list(type(str('NewForm'), (Mixin, ModelForm, Form), {})().fields.keys()), ['name'])
+        self.assertEqual(list(type(str('NewForm'), (ModelForm, Mixin, Form), {})().fields.keys()), ['name'])
+        self.assertEqual(list(type(str('NewForm'), (ModelForm, Form, Mixin), {})().fields.keys()), ['name', 'age'])
+        self.assertEqual(list(type(str('NewForm'), (ModelForm, Form), {'age': None})().fields.keys()), ['name'])