Allow correspondents to be deleted without deleting their documents

Fixes #235

src/documents/tests/factories.py

@@ -0,0 +1,17 @@
+import factory
+
+from ..models import Document, Correspondent
+
+
+class CorrespondentFactory(factory.DjangoModelFactory):
+
+    class Meta:
+        model = Correspondent
+
+    name = factory.Faker("name")
+
+
+class DocumentFactory(factory.DjangoModelFactory):
+
+    class Meta:
+        model = Document

src/documents/tests/test_models.py

@@ -0,0 +1,31 @@
+from django.test import TestCase
+
+from ..models import Document, Correspondent
+from .factories import DocumentFactory, CorrespondentFactory
+
+
+class CorrespondentTestCase(TestCase):
+
+    def test___str__(self):
+        for s in ("test", "οχι", "test with fun_charÅc'\"terß"):
+            correspondent = CorrespondentFactory.create(name=s)
+            self.assertEqual(str(correspondent), s)
+
+
+class DocumentTestCase(TestCase):
+
+    def test_correspondent_deletion_does_not_cascade(self):
+
+        self.assertEqual(Correspondent.objects.all().count(), 0)
+        correspondent = CorrespondentFactory.create()
+        self.assertEqual(Correspondent.objects.all().count(), 1)
+
+        self.assertEqual(Document.objects.all().count(), 0)
+        DocumentFactory.create(correspondent=correspondent)
+        self.assertEqual(Document.objects.all().count(), 1)
+        self.assertIsNotNone(Document.objects.all().first().correspondent)
+
+        correspondent.delete()
+        self.assertEqual(Correspondent.objects.all().count(), 0)
+        self.assertEqual(Document.objects.all().count(), 1)
+        self.assertIsNone(Document.objects.all().first().correspondent)