From 3a23e8ed29180e914883a263ec83373ecbd02efa Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Mon, 10 Jan 2022 16:48:05 -0500 Subject: remove internal use of metaclasses All but one metaclass used internally can now be replaced using __init_subclass__(). Within this patch we remove: * events._EventMeta * sql.visitors.TraversibleType * sql.visitors.InternalTraversibleType * testing.fixtures.FindFixture * testing.fixtures.FindFixtureDeclarative * langhelpers.EnsureKWArgType * sql.functions._GenericMeta * sql.type_api.VisitableCheckKWArg (was a mixture of TraversibleType and EnsureKWArgType) The remaining internal class is MetaOptions used by the sql.Options object which is in turn currently mostly for ORM internal use, as this type implements class level overrides for the ``+`` operator. For declarative, removing DeclarativeMeta in place of an `__init_subclass__()` class would not be fully feasible as it would break backwards compatibility with applications that refer to this class explicitly, but also DeclarativeMeta intercepts class-level attribute set and delete operations which is a widely used pattern. An option for declarative base to use `__init_subclass__()` should be provided but this is out of scope for this particular change. Change-Id: I8aa898c7ab59d887739037d34b1cbab36521ab78 References: #6810 --- lib/sqlalchemy/sql/expression.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/sqlalchemy/sql/expression.py') diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 2a3cd07d0..54f67b930 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -94,6 +94,7 @@ from .base import _from_objects from .base import _select_iterables from .base import ColumnCollection from .base import Executable +from .cache_key import CacheKey from .dml import Delete from .dml import Insert from .dml import Update @@ -173,7 +174,6 @@ from .selectable import TableValuedAlias from .selectable import TextAsFrom from .selectable import TextualSelect from .selectable import Values -from .traversals import CacheKey from .visitors import Visitable from ..util.langhelpers import public_factory -- cgit v1.2.1