Refs #22875 -- Fixed an optimizer test to use a valid scenario.

An explicit intermediary many-to-many relationship must declare forward and
reverse foreign keys. The original issue was in the autodetector as these
operations shouldn't have been generated in this order in the first place
which is tested by AutodetectorTests.test_create_with_through_model.

1 files changed, 9 insertions, 5 deletions

diff --git a/tests/migrations/test_optimizer.py b/tests/migrations/test_optimizer.py
index 0a13ef290f..7a1876a508 100644
--- a/tests/migrations/test_optimizer.py
+++ b/tests/migrations/test_optimizer.py
@@ -318,14 +318,18 @@ class OptimizerTests(SimpleTestCase):
         AddField should NOT optimize into CreateModel if it's an M2M using a
         through that's created between them.
         """
-        # Note: The middle model is not actually a valid through model,
-        # but that doesn't matter, as we never render it.
         self.assertDoesNotOptimize(
             [
-                migrations.CreateModel("Foo", [("name", models.CharField(max_length=255))]),
-                migrations.CreateModel("LinkThrough", []),
+                migrations.CreateModel('Employee', []),
+                migrations.CreateModel('Employer', []),
+                migrations.CreateModel('Employment', [
+                    ('employee', models.ForeignKey('migrations.Employee', models.CASCADE)),
+                    ('employment', models.ForeignKey('migrations.Employer', models.CASCADE)),
+                ]),
                 migrations.AddField(
-                    "Foo", "link", models.ManyToManyField("migrations.Link", through="migrations.LinkThrough")
+                    'Employer', 'employees', models.ManyToManyField(
+                        'migrations.Employee', through='migrations.Employment',
+                    )
                 ),
             ],
         )