From 0b571753a89f2a7a34c76dea5ee81f821b980779 Mon Sep 17 00:00:00 2001 From: Andrew Godwin Date: Mon, 23 Jun 2014 20:39:17 -0700 Subject: [PATCH] Fixed #22889: Unneeded to_field in fk.deconstruct causing swap issues --- django/db/models/fields/related.py | 3 ++- tests/field_deconstruction/tests.py | 9 +++++++++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py index 9452b06dbd..ac53515c1b 100644 --- a/django/db/models/fields/related.py +++ b/django/db/models/fields/related.py @@ -1673,7 +1673,8 @@ class ForeignKey(ForeignObject): if self.rel.on_delete is not CASCADE: kwargs['on_delete'] = self.rel.on_delete # Rel needs more work. - if self.rel.field_name: + to_meta = getattr(self.rel.to, "_meta", None) + if self.rel.field_name and (not to_meta or (to_meta.pk and self.rel.field_name != to_meta.pk.name)): kwargs['to_field'] = self.rel.field_name return name, path, args, kwargs diff --git a/tests/field_deconstruction/tests.py b/tests/field_deconstruction/tests.py index 0e75388747..04d4c6a6ad 100644 --- a/tests/field_deconstruction/tests.py +++ b/tests/field_deconstruction/tests.py @@ -169,7 +169,10 @@ class FieldDeconstructionTests(TestCase): def test_foreign_key(self): # Test basic pointing + from django.contrib.auth.models import Permission field = models.ForeignKey("auth.Permission") + field.rel.to = Permission + field.rel.field_name = "id" name, path, args, kwargs = field.deconstruct() self.assertEqual(path, "django.db.models.ForeignKey") self.assertEqual(args, []) @@ -194,6 +197,12 @@ class FieldDeconstructionTests(TestCase): self.assertEqual(path, "django.db.models.ForeignKey") self.assertEqual(args, []) self.assertEqual(kwargs, {"to": "auth.User", "on_delete": models.SET_NULL}) + # Test to_field preservation + field = models.ForeignKey("auth.Permission", to_field="foobar") + name, path, args, kwargs = field.deconstruct() + self.assertEqual(path, "django.db.models.ForeignKey") + self.assertEqual(args, []) + self.assertEqual(kwargs, {"to": "auth.Permission", "to_field": "foobar"}) @override_settings(AUTH_USER_MODEL="auth.Permission") def test_foreign_key_swapped(self):