1 files changed, 50 insertions, 0 deletions
diff --git a/tests/null_fk/models.py b/tests/null_fk/models.py
new file mode 100644
index 0000000000..c86ee8a5a9
--- /dev/null
+++ b/tests/null_fk/models.py
@@ -0,0 +1,50 @@
+"""
+Regression tests for proper working of ForeignKey(null=True).
+"""
+
+from django.db import models
+from django.utils.encoding import python_2_unicode_compatible
+
+
+class SystemDetails(models.Model):
+    details = models.TextField()
+
+class SystemInfo(models.Model):
+    system_details = models.ForeignKey(SystemDetails)
+    system_name = models.CharField(max_length=32)
+
+class Forum(models.Model):
+    system_info = models.ForeignKey(SystemInfo)
+    forum_name = models.CharField(max_length=32)
+
+@python_2_unicode_compatible
+class Post(models.Model):
+    forum = models.ForeignKey(Forum, null=True)
+    title = models.CharField(max_length=32)
+
+    def __str__(self):
+        return self.title
+
+@python_2_unicode_compatible
+class Comment(models.Model):
+    post = models.ForeignKey(Post, null=True)
+    comment_text = models.CharField(max_length=250)
+
+    class Meta:
+        ordering = ('comment_text',)
+
+    def __str__(self):
+        return self.comment_text
+
+# Ticket 15823
+
+class Item(models.Model):
+    title = models.CharField(max_length=100)
+
+class PropertyValue(models.Model):
+    label = models.CharField(max_length=100)
+
+class Property(models.Model):
+    item = models.ForeignKey(Item, related_name='props')
+    key = models.CharField(max_length=100)
+    value = models.ForeignKey(PropertyValue, null=True)