Made nested deconstruction support both forms of deconstruct()

Nested deconstruction should (silently) handle Field.deconstruct() as
well as other arbitrary deconstructable objects. This allows having a
field in the deconstruction of another field.

1 files changed, 12 insertions, 0 deletions

diff --git a/tests/migrations/test_autodetector.py b/tests/migrations/test_autodetector.py
index 54361f00ed..88b67d2c23 100644
--- a/tests/migrations/test_autodetector.py
+++ b/tests/migrations/test_autodetector.py
@@ -28,6 +28,8 @@ class AutodetectorTests(TestCase):
     author_name_default = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200, default='Ada Lovelace'))])
     author_name_deconstructable_1 = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200, default=DeconstructableObject()))])
     author_name_deconstructable_2 = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200, default=DeconstructableObject()))])
+    author_name_deconstructable_3 = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200, default=models.IntegerField()))])
+    author_name_deconstructable_4 = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200, default=models.IntegerField()))])
     author_with_book = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200)), ("book", models.ForeignKey("otherapp.Book"))])
     author_renamed_with_book = ModelState("testapp", "Writer", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200)), ("book", models.ForeignKey("otherapp.Book"))])
     author_with_publisher_string = ModelState("testapp", "Author", [("id", models.AutoField(primary_key=True)), ("name", models.CharField(max_length=200)), ("publisher_name", models.CharField(max_length=200))])
@@ -576,6 +578,16 @@ class AutodetectorTests(TestCase):
         changes = autodetector._detect_changes()
         self.assertEqual(changes, {})
 
+    def test_deconstruct_field_kwarg(self):
+        """
+        Field instances are handled correctly by nested deconstruction.
+        """
+        before = self.make_project_state([self.author_name_deconstructable_3])
+        after = self.make_project_state([self.author_name_deconstructable_4])
+        autodetector = MigrationAutodetector(before, after)
+        changes = autodetector._detect_changes()
+        self.assertEqual(changes, {})
+
     def test_replace_string_with_foreignkey(self):
         """
         Adding an FK in the same "spot" as a deleted CharField should work. (#22300).