Keep address migration identifiers PostgreSQL-safe

tests/test_migrations.py

@@ -7,11 +7,22 @@ from pathlib import Path
 from alembic.runtime.migration import MigrationContext
 from sqlalchemy import create_engine, inspect
 
+from govoplan_addresses.backend.db.models import Base
 from govoplan_addresses.backend.manifest import get_manifest
 from govoplan_core.db.migrations import migrate_database
 
 
 class AddressesMigrationTests(unittest.TestCase):
+    def test_schema_identifiers_fit_postgresql_limit(self) -> None:
+        overlong_indexes = sorted(
+            index.name
+            for table in Base.metadata.tables.values()
+            if table.name.startswith("addresses_")
+            for index in table.indexes
+            if index.name and len(index.name) > 63
+        )
+        self.assertEqual([], overlong_indexes)
+
     def test_fresh_database_reaches_import_profile_head(self) -> None:
         with tempfile.TemporaryDirectory(prefix="govoplan-addresses-migration-") as directory:
             url = f"sqlite:///{Path(directory) / 'addresses.db'}"