mock _NONE_NAME for < 1.3.24

Fixed regression where Alembic would not run with older SQLAlchemy 1.3
versions prior to 1.3.24 due to a missing symbol. Workarounds have been
applied for older 1.3 versions.

Change-Id: Ie7b5f6295e55276f0e912bf2b10b8c96dad171b9
Fixes: #1196

1 files changed, 5 insertions, 1 deletions

diff --git a/alembic/util/sqla_compat.py b/alembic/util/sqla_compat.py
index 2cc070b..a767e7d 100644
--- a/alembic/util/sqla_compat.py
+++ b/alembic/util/sqla_compat.py
@@ -27,7 +27,6 @@ from sqlalchemy.sql.elements import ColumnClause
 from sqlalchemy.sql.elements import quoted_name
 from sqlalchemy.sql.elements import TextClause
 from sqlalchemy.sql.elements import UnaryExpression
-from sqlalchemy.sql.naming import _NONE_NAME as _NONE_NAME
 from sqlalchemy.sql.visitors import traverse
 from typing_extensions import TypeGuard
 
@@ -66,6 +65,11 @@ sqla_14_26 = _vers >= (1, 4, 26)
 sqla_2 = _vers >= (2,)
 sqlalchemy_version = __version__
 
+try:
+    from sqlalchemy.sql.naming import _NONE_NAME as _NONE_NAME
+except ImportError:
+    from sqlalchemy.sql.elements import _NONE_NAME as _NONE_NAME  # type: ignore  # noqa: E501
+
 
 if sqla_14:
     # when future engine merges, this can be again based on version string