Fixed #8134 -- Corrected serialization of m2m fields with intermediat…

…e models. Thanks to Rock Howard for the report, and kire for the test case.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8321 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/serializers/python.py

@@ -49,8 +49,9 @@ def handle_fk_field(self, obj, field):
         self._current[field.name] = smart_unicode(related, strings_only=True)
 
     def handle_m2m_field(self, obj, field):
-        self._current[field.name] = [smart_unicode(related._get_pk_val(), strings_only=True)
-                           for related in getattr(obj, field.name).iterator()]
+        if field.creates_table:
+            self._current[field.name] = [smart_unicode(related._get_pk_val(), strings_only=True)
+                               for related in getattr(obj, field.name).iterator()]
 
     def getvalue(self):
         return self.objects

django/core/serializers/xml_serializer.py

@@ -100,10 +100,11 @@ def handle_m2m_field(self, obj, field):
         serialized as references to the object's PK (i.e. the related *data*
         is not dumped, just the relation).
         """
-        self._start_relational_field(field)
-        for relobj in getattr(obj, field.name).iterator():
-            self.xml.addQuickElement("object", attrs={"pk" : smart_unicode(relobj._get_pk_val())})
-        self.xml.endElement("field")
+        if field.creates_table:
+            self._start_relational_field(field)
+            for relobj in getattr(obj, field.name).iterator():
+                self.xml.addQuickElement("object", attrs={"pk" : smart_unicode(relobj._get_pk_val())})
+            self.xml.endElement("field")
 
     def _start_relational_field(self, field):
         """

tests/regressiontests/m2m_through_regress/models.py

@@ -1,20 +1,21 @@
-from django.db import models
 from datetime import datetime
 from django.contrib.auth.models import User
+from django.core import management
+from django.db import models
 
 # Forward declared intermediate model
 class Membership(models.Model):
     person = models.ForeignKey('Person')
     group = models.ForeignKey('Group')
-    date_joined = models.DateTimeField(default=datetime.now)
+    price = models.IntegerField(default=100)
 
     def __unicode__(self):
         return "%s is a member of %s" % (self.person.name, self.group.name)
 
 class UserMembership(models.Model):
     user = models.ForeignKey(User)
     group = models.ForeignKey('Group')
-    date_joined = models.DateTimeField(default=datetime.now)
+    price = models.IntegerField(default=100)
 
     def __unicode__(self):
         return "%s is a user and member of %s" % (self.user.username, self.group.name)
@@ -99,4 +100,141 @@ def __unicode__(self):
 >>> roll.user_members.all()
 [<User: frank>]
 
+# Regression test for #8134 -- 
+# m2m-through models shouldn't be serialized as m2m fields on the model.
+# Dump the current contents of the database as a JSON fixture
+>>> management.call_command('dumpdata', 'm2m_through_regress', format='json', indent=2)
+[
+  {
+    "pk": 1, 
+    "model": "m2m_through_regress.membership", 
+    "fields": {
+      "person": 1, 
+      "price": 100, 
+      "group": 1
+    }
+  }, 
+  {
+    "pk": 2, 
+    "model": "m2m_through_regress.membership", 
+    "fields": {
+      "person": 1, 
+      "price": 100, 
+      "group": 2
+    }
+  }, 
+  {
+    "pk": 3, 
+    "model": "m2m_through_regress.membership", 
+    "fields": {
+      "person": 2, 
+      "price": 100, 
+      "group": 1
+    }
+  }, 
+  {
+    "pk": 1, 
+    "model": "m2m_through_regress.usermembership", 
+    "fields": {
+      "price": 100, 
+      "group": 1, 
+      "user": 1
+    }
+  }, 
+  {
+    "pk": 2, 
+    "model": "m2m_through_regress.usermembership", 
+    "fields": {
+      "price": 100, 
+      "group": 2, 
+      "user": 1
+    }
+  }, 
+  {
+    "pk": 3, 
+    "model": "m2m_through_regress.usermembership", 
+    "fields": {
+      "price": 100, 
+      "group": 1, 
+      "user": 2
+    }
+  }, 
+  {
+    "pk": 1, 
+    "model": "m2m_through_regress.person", 
+    "fields": {
+      "name": "Bob"
+    }
+  }, 
+  {
+    "pk": 2, 
+    "model": "m2m_through_regress.person", 
+    "fields": {
+      "name": "Jim"
+    }
+  }, 
+  {
+    "pk": 1, 
+    "model": "m2m_through_regress.group", 
+    "fields": {
+      "name": "Rock"
+    }
+  }, 
+  {
+    "pk": 2, 
+    "model": "m2m_through_regress.group", 
+    "fields": {
+      "name": "Roll"
+    }
+  }
+]
+
+# Check the XML serializer too, since it doesn't use the common implementation
+>>> management.call_command('dumpdata', 'm2m_through_regress', format='xml', indent=2)
+<?xml version="1.0" encoding="utf-8"?>
+<django-objects version="1.0">
+  <object pk="1" model="m2m_through_regress.membership">
+    <field to="m2m_through_regress.person" name="person" rel="ManyToOneRel">1</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">1</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="2" model="m2m_through_regress.membership">
+    <field to="m2m_through_regress.person" name="person" rel="ManyToOneRel">1</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">2</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="3" model="m2m_through_regress.membership">
+    <field to="m2m_through_regress.person" name="person" rel="ManyToOneRel">2</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">1</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="1" model="m2m_through_regress.usermembership">
+    <field to="auth.user" name="user" rel="ManyToOneRel">1</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">1</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="2" model="m2m_through_regress.usermembership">
+    <field to="auth.user" name="user" rel="ManyToOneRel">1</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">2</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="3" model="m2m_through_regress.usermembership">
+    <field to="auth.user" name="user" rel="ManyToOneRel">2</field>
+    <field to="m2m_through_regress.group" name="group" rel="ManyToOneRel">1</field>
+    <field type="IntegerField" name="price">100</field>
+  </object>
+  <object pk="1" model="m2m_through_regress.person">
+    <field type="CharField" name="name">Bob</field>
+  </object>
+  <object pk="2" model="m2m_through_regress.person">
+    <field type="CharField" name="name">Jim</field>
+  </object>
+  <object pk="1" model="m2m_through_regress.group">
+    <field type="CharField" name="name">Rock</field>
+  </object>
+  <object pk="2" model="m2m_through_regress.group">
+    <field type="CharField" name="name">Roll</field>
+  </object>
+</django-objects>
+
 """}

tests/regressiontests/serializers_regress/models.py

@@ -132,6 +132,14 @@ class FKDataToField(models.Model):
 class FKDataToO2O(models.Model):
     data = models.ForeignKey(O2OData, null=True)
 
+class M2MIntermediateData(models.Model):
+    data = models.ManyToManyField(Anchor, null=True, through='Intermediate')
+
+class Intermediate(models.Model):
+    left = models.ForeignKey(M2MIntermediateData)
+    right = models.ForeignKey(Anchor)
+    extra = models.CharField(max_length=30, blank=True, default="doesn't matter")
+
 # The following test classes are for validating the
 # deserialization of objects that use a user-defined
 # field as the primary key.
@@ -243,3 +251,4 @@ class InheritBaseModel(BaseModel):
 class ExplicitInheritBaseModel(BaseModel):
     parent = models.OneToOneField(BaseModel)
     child_data = models.IntegerField()
+

tests/regressiontests/serializers_regress/tests.py

@@ -54,6 +54,20 @@ def m2m_create(pk, klass, data):
     instance.data = data
     return [instance]
 
+def im2m_create(pk, klass, data):
+    instance = klass(id=pk)
+    models.Model.save_base(instance, raw=True)
+    return [instance]
+
+def im_create(pk, klass, data):
+    instance = klass(id=pk)
+    setattr(instance, 'right_id', data['right'])
+    setattr(instance, 'left_id', data['left'])
+    if 'extra' in data:
+        setattr(instance, 'extra', data['extra'])
+    models.Model.save_base(instance, raw=True)
+    return [instance]
+
 def o2o_create(pk, klass, data):
     instance = klass()
     instance.data_id = data
@@ -99,6 +113,19 @@ def m2m_compare(testcase, pk, klass, data):
     instance = klass.objects.get(id=pk)
     testcase.assertEqual(data, [obj.id for obj in instance.data.all()])
 
+def im2m_compare(testcase, pk, klass, data):
+    instance = klass.objects.get(id=pk)
+    #actually nothing else to check, the instance just should exist
+
+def im_compare(testcase, pk, klass, data):
+    instance = klass.objects.get(id=pk)
+    testcase.assertEqual(data['left'], instance.left_id)
+    testcase.assertEqual(data['right'], instance.right_id)
+    if 'extra' in data:
+        testcase.assertEqual(data['extra'], instance.extra)
+    else:
+        testcase.assertEqual("doesn't matter", instance.extra)
+
 def o2o_compare(testcase, pk, klass, data):
     instance = klass.objects.get(data=data)
     testcase.assertEqual(data, instance.data_id)
@@ -119,6 +146,8 @@ def inherited_compare(testcase, pk, klass, data):
 generic_obj = (generic_create, generic_compare)
 fk_obj = (fk_create, fk_compare)
 m2m_obj = (m2m_create, m2m_compare)
+im2m_obj = (im2m_create, im2m_compare)
+im_obj = (im_create, im_compare)
 o2o_obj = (o2o_create, o2o_compare)
 pk_obj = (pk_create, pk_compare)
 inherited_obj = (inherited_create, inherited_compare)
@@ -231,6 +260,20 @@ def inherited_compare(testcase, pk, klass, data):
     (fk_obj, 452, FKDataToField, None),
 
     (fk_obj, 460, FKDataToO2O, 300),
+
+    (im2m_obj, 470, M2MIntermediateData, None),
+
+    #testing post- and prereferences and extra fields
+    (im_obj, 480, Intermediate, {'right': 300, 'left': 470}),
+    (im_obj, 481, Intermediate, {'right': 300, 'left': 490}), 
+    (im_obj, 482, Intermediate, {'right': 500, 'left': 470}), 
+    (im_obj, 483, Intermediate, {'right': 500, 'left': 490}), 
+    (im_obj, 484, Intermediate, {'right': 300, 'left': 470, 'extra': "extra"}), 
+    (im_obj, 485, Intermediate, {'right': 300, 'left': 490, 'extra': "extra"}), 
+    (im_obj, 486, Intermediate, {'right': 500, 'left': 470, 'extra': "extra"}), 
+    (im_obj, 487, Intermediate, {'right': 500, 'left': 490, 'extra': "extra"}), 
+
+    (im2m_obj, 490, M2MIntermediateData, []),
 
     (data_obj, 500, Anchor, "Anchor 3"),
     (data_obj, 501, Anchor, "Anchor 4"),