Add tests

src/django_linear_migrations/apps.py

@@ -5,7 +5,7 @@
 from importlib import import_module, reload
 from pathlib import Path
 from types import ModuleType
-from typing import Generator, Iterable
+from typing import Generator, Iterable, cast
 
 from django.apps import AppConfig, apps
 from django.conf import settings
@@ -111,12 +111,8 @@ def names(self) -> set[str]:
     def plan(self) -> list[tuple[str, str]]:
         loader = MigrationLoader(connections[DEFAULT_DB_ALIAS])
         nodes = [key for key in loader.graph.leaf_nodes() if key[0] in self.app_label]
-        plan = []
-        for node in nodes:
-            for migration in loader.graph.forwards_plan(node):
-                if migration not in plan:
-                    plan.append(migration)
-        return plan
+        plan = loader.graph._generate_plan(nodes, at_end=True)
+        return cast(list[tuple[str, str]], plan)
 
 
 def check_max_migration_files(

tests/test_checks.py

@@ -2,14 +2,15 @@
 
 import sys
 import time
+from textwrap import dedent
 
 import pytest
-from django.test import SimpleTestCase, override_settings
+from django.test import TestCase, override_settings
 
 from django_linear_migrations.apps import check_max_migration_files
 
 
-class CheckMaxMigrationFilesTests(SimpleTestCase):
+class CheckMaxMigrationFilesTests(TestCase):
     @pytest.fixture(autouse=True)
     def tmp_path_fixture(self, tmp_path):
         migrations_module_name = "migrations" + str(time.time()).replace(".", "")
@@ -88,8 +89,24 @@ def test_dlm_E003(self):
 
     def test_dlm_E004(self):
         (self.migrations_dir / "__init__.py").touch()
-        (self.migrations_dir / "0001_initial.py").touch()
-        (self.migrations_dir / "0002_updates.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
+        (self.migrations_dir / "0002_updates.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
         (self.migrations_dir / "max_migration.txt").write_text("0001_initial\n")
 
         result = check_max_migration_files()
@@ -102,9 +119,16 @@ def test_dlm_E004(self):
         )
 
     def test_okay(self):
+        migrations_txt = dedent(
+            """
+            from django.db import migrations
+            class Migration(migrations.Migration):
+                pass
+            """
+        )
         (self.migrations_dir / "__init__.py").touch()
-        (self.migrations_dir / "0001_initial.py").touch()
-        (self.migrations_dir / "0002_updates.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(migrations_txt)
+        (self.migrations_dir / "0002_updates.py").write_text(migrations_txt)
         (self.migrations_dir / "max_migration.txt").write_text("0002_updates\n")
 
         result = check_max_migration_files()

tests/test_create_max_migration_files.py

@@ -3,6 +3,7 @@
 import sys
 import time
 from io import StringIO
+from textwrap import dedent
 
 import pytest
 from django.core.management import call_command
@@ -98,7 +99,15 @@ def test_success_dry_run(self):
 
     def test_success(self):
         (self.migrations_dir / "__init__.py").touch()
-        (self.migrations_dir / "0001_initial.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
 
         out, err, returncode = self.call_command()
 
@@ -121,7 +130,15 @@ def test_success_already_exists(self):
 
     def test_success_recreate(self):
         (self.migrations_dir / "__init__.py").touch()
-        (self.migrations_dir / "0001_initial.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
         (self.migrations_dir / "max_migration.txt").write_text("0001_initial\n")
 
         out, err, returncode = self.call_command("--recreate")
@@ -143,7 +160,15 @@ def test_success_recreate_dry_run(self):
 
     def test_success_specific_app_label(self):
         (self.migrations_dir / "__init__.py").touch()
-        (self.migrations_dir / "0001_initial.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
 
         out, err, returncode = self.call_command("testapp")
 
@@ -168,3 +193,41 @@ def test_success_ignored_app_label(self):
         assert out == "No max_migration.txt files need creating.\n"
         assert err == ""
         assert returncode == 0
+
+    def test_success_custom_migration_name(self):
+        (self.migrations_dir / "__init__.py").touch()
+        (self.migrations_dir / "0001_initial.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    pass
+                """
+            )
+        )
+        (self.migrations_dir / "custom_name.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    dependencies = [('testapp', '0001_initial')]
+                """
+            )
+        )
+        (self.migrations_dir / "0002_updates.py").write_text(
+            dedent(
+                """
+                from django.db import migrations
+                class Migration(migrations.Migration):
+                    dependencies = [('testapp', 'custom_name')]
+                """
+            )
+        )
+
+        out, err, returncode = self.call_command()
+
+        assert out == "Created max_migration.txt for testapp.\n"
+        assert err == ""
+        assert returncode == 0
+        max_migration_txt = self.migrations_dir / "max_migration.txt"
+        assert max_migration_txt.read_text() == "0002_updates\n"