Adding tests for check_migrations.

tests/migrations/test_checks.py

@@ -0,0 +1,43 @@
+# encoding: utf8
+from django.core import checks
+from django.core.checks.migrations import check_migrations
+from django.test import TestCase, override_settings
+
+from .test_base import MigrationTestBase
+
+
+class CheckMigrationTests(MigrationTestBase):
+    """
+    Test checks for unapplied migrations.
+    """
+
+    @override_settings(MIGRATION_MODULES={"migrations": "migrations.test_migrations"})
+    def test_unapplied(self):
+        """
+        check_migrations should return a warning when there are unapplied migrations.
+        """
+        expected = [
+            checks.Warning(
+                "You have unapplied migrations; "
+                "your app may not work properly until they are applied.",
+                hint="Run 'python manage.py migrate' to apply them.",
+            )
+        ]
+        errors = check_migrations()
+        self.assertEqual(errors, expected)
+
+    @override_settings(MIGRATION_MODULES={"migrations": "migrations.test_migrations"}, DATABASES={})
+    def test_no_databases(self):
+        """
+        Migration checks should not consider unapplied migrations if there is
+        no database configured.
+        """
+        errors = check_migrations()
+        self.assertEqual(errors, [])
+
+    def test_no_unapplied(self):
+        """
+        No warning should be issued if all migrations have been applied.
+        """
+        errors = check_migrations()
+        self.assertEqual(errors, [])