Fix: fix broken migration in 3.0.1 (#13242)

src/paperless_mail/tests/test_migrations.py

@@ -0,0 +1,37 @@
+import importlib
+
+from django.db import migrations
+
+
+def test_optimize_integer_fields_preserves_released_migration_history():
+    migration_module = importlib.import_module(
+        "paperless_mail.migrations.0002_optimize_integer_field_sizes",
+    )
+
+    assert migration_module.Migration.dependencies == [
+        ("paperless_mail", "0001_squashed"),
+    ]
+
+
+def test_mailrule_maximum_age_is_clamped_before_non_atomic_alter():
+    migration_module = importlib.import_module(
+        "paperless_mail.migrations.0002_optimize_integer_field_sizes",
+    )
+    migration = migration_module.Migration
+
+    clamp_index = next(
+        index
+        for index, operation in enumerate(migration.operations)
+        if isinstance(operation, migrations.RunPython)
+        and operation.code is migration_module.clamp_mailrule_maximum_age
+    )
+    alter_index = next(
+        index
+        for index, operation in enumerate(migration.operations)
+        if isinstance(operation, migrations.AlterField)
+        and operation.model_name == "mailrule"
+        and operation.name == "maximum_age"
+    )
+
+    assert migration.atomic is False
+    assert clamp_index < alter_index