Fixed a bug where simple-history can't handle foreign keys pointing to

one to one fields.

Author: daniell

.gitignore

@@ -9,3 +9,6 @@ MANIFEST
 .tox/
 htmlcov/
 test_files/
+/.ve
+/.project
+/.pydevproject

AUTHORS.rst

@@ -4,6 +4,7 @@ Authors
 - Aleksey Kladov
 - Corey Bertram
 - Damien Nozay
+- Daniel Levy
 - George Vilches
 - Joao Pedro Francese
 - Jonathan Sanchez

CHANGES.rst

@@ -3,6 +3,7 @@ Changes
 
 tip (unreleased)
 ----------------
+- Fixed error that occurs when models have a foreign key pointing to a one to one field.
 
 1.3.0 (2013-05-17)
 ------------------

simple_history/models.py

@@ -179,13 +179,25 @@ class CustomForeignKey(parent_type):
 
         def get_attname(self):
             return self.name
-
-        def do_related_class(self, other, cls):
+        
+        def get_field(self, other, cls):
             # this hooks into contribute_to_class() and this is
             # called specifically after the class_prepared signal
             to_field = copy.copy(self.rel.to._meta.pk)
             field = self
-            if isinstance(to_field, models.AutoField):
+            if isinstance(to_field, models.OneToOneField):
+                #HACK This creates a new custom foreign key based on to_field,
+                # and calls itself with that, effectively making the calls
+                # recursive
+                temp_field = self.__class__(to_field.rel.to._meta.object_name)
+                for key, val in to_field.__dict__.items():
+                    if (isinstance(key, basestring)
+                            and not key.startswith('_')):
+                        setattr(temp_field, key, val)
+                field = self.__class__.get_field(
+                         temp_field, other, to_field.rel.to)
+                
+            elif isinstance(to_field, models.AutoField):
                 field.__class__ = models.IntegerField
             else:
                 field.__class__ = to_field.__class__
@@ -216,6 +228,11 @@ def do_related_class(self, other, cls):
                             and not key.startswith(excluded_prefixes)
                             and not key in excluded_attributes):
                         setattr(field, key, val)
+            return field
+        
+        def do_related_class(self, other, cls):
+            field = self.get_field(other, cls)
+            
             transform_field(field)
             field.rel = None
 

simple_history/tests/models.py

@@ -61,7 +61,12 @@ class Document(models.Model):
     def _history_user(self):
         return self.changed_by
 
+class Profile(User):
+    date_of_birth = models.DateField()
 
+class AdminProfile(models.Model):
+    profile = models.ForeignKey(Profile)
+    
 class State(models.Model):
     library = models.ForeignKey('Library', null=True)
     history = HistoricalRecords()
@@ -71,6 +76,11 @@ class Book(models.Model):
     isbn = models.CharField(max_length=15, primary_key=True)
     history = HistoricalRecords()
 
+class HardbackBook(Book):
+    price = models.FloatField()
+
+class Bookcase(models.Model):
+    books = models.ForeignKey(HardbackBook)
 
 class Library(models.Model):
     book = models.ForeignKey(Book, null=True)

simple_history/tests/tests.py

@@ -6,6 +6,9 @@
 from django_webtest import WebTest
 from django.core.files.base import ContentFile
 from django.core.urlresolvers import reverse
+from simple_history.tests.models import Profile, AdminProfile, Bookcase
+from django.db import models
+from simple_history.models import HistoricalRecords
 try:
     from django.contrib.auth import get_user_model
     User = get_user_model()
@@ -219,7 +222,6 @@ def test_raw_save(self):
             'history_type': "~",
         })
 
-
 class RegisterTest(TestCase):
     def test_register_no_args(self):
         self.assertEqual(len(Choice.history.all()), 0)
@@ -243,6 +245,25 @@ def test_reregister(self):
         self.assertTrue(hasattr(User, 'histories'))
         self.assertFalse(hasattr(User, 'again'))
 
+class CreateHistoryModelTests(TestCase):
+
+    def test_create_history_model_with_one_to_one_field_to_integer_field(self):
+        records = HistoricalRecords()
+        records.module = AdminProfile.__module__
+        try:
+            records.create_history_model(AdminProfile)
+        except:
+            self.fail("SimpleHistory should handle foreign keys to one to one"
+                      "fields to integer fields without throwing an exception.")
+    
+    def test_create_history_model_with_one_to_one_field_to_char_field(self):
+        records = HistoricalRecords()
+        records.module = Bookcase.__module__
+        try:
+            records.create_history_model(Bookcase)
+        except:
+            self.fail("SimpleHistory should handle foreign keys to one to one"
+                      "fields to char fields without throwing an exception.")
 
 class AppLabelTest(TestCase):
     def get_table_name(self, manager):