Add standalone orm.close_all method and deprecate SessionMaker.close_all

Added a new function :func:`.close_all_sessions` which takes
over the task of the :meth:`.Session.close_all` method, which
is now deprecated as this is confusing as a classmethod.
Pull request courtesy Augustin Trancart.

Fixes: #4412

Closes: #4438
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/4438
Pull-request-sha: 7833d12a9898c82d50716427144bf3276c22ab3f

Change-Id: Ib35eaa520ae886f3f8f550f9712fc3b139e00b60

3 files changed, 6 insertions, 3 deletions

diff --git a/test/ext/declarative/test_basic.py b/test/ext/declarative/test_basic.py
index 990262f2c..0f0035019 100644
--- a/test/ext/declarative/test_basic.py
+++ b/test/ext/declarative/test_basic.py
@@ -19,6 +19,7 @@ from sqlalchemy.ext.hybrid import hybrid_property
 from sqlalchemy.orm import backref
 from sqlalchemy.orm import class_mapper
 from sqlalchemy.orm import clear_mappers
+from sqlalchemy.orm import close_all_sessions
 from sqlalchemy.orm import column_property
 from sqlalchemy.orm import composite
 from sqlalchemy.orm import configure_mappers
@@ -60,7 +61,7 @@ class DeclarativeTestBase(
         Base = decl.declarative_base(testing.db)
 
     def teardown(self):
-        Session.close_all()
+        close_all_sessions()
         clear_mappers()
         Base.metadata.drop_all()
 
diff --git a/test/ext/declarative/test_inheritance.py b/test/ext/declarative/test_inheritance.py
index 97c7dcd7c..17b915da0 100644
--- a/test/ext/declarative/test_inheritance.py
+++ b/test/ext/declarative/test_inheritance.py
@@ -10,6 +10,7 @@ from sqlalchemy.ext.declarative import declared_attr
 from sqlalchemy.ext.declarative import has_inherited_table
 from sqlalchemy.orm import class_mapper
 from sqlalchemy.orm import clear_mappers
+from sqlalchemy.orm import close_all_sessions
 from sqlalchemy.orm import configure_mappers
 from sqlalchemy.orm import create_session
 from sqlalchemy.orm import deferred
@@ -39,7 +40,7 @@ class DeclarativeTestBase(fixtures.TestBase, testing.AssertsExecutionResults):
         Base = decl.declarative_base(testing.db)
 
     def teardown(self):
-        Session.close_all()
+        close_all_sessions()
         clear_mappers()
         Base.metadata.drop_all()
 
diff --git a/test/ext/declarative/test_mixin.py b/test/ext/declarative/test_mixin.py
index 7fec77270..ef9bbd354 100644
--- a/test/ext/declarative/test_mixin.py
+++ b/test/ext/declarative/test_mixin.py
@@ -11,6 +11,7 @@ from sqlalchemy.ext.declarative import declared_attr
 from sqlalchemy.orm import base as orm_base
 from sqlalchemy.orm import class_mapper
 from sqlalchemy.orm import clear_mappers
+from sqlalchemy.orm import close_all_sessions
 from sqlalchemy.orm import column_property
 from sqlalchemy.orm import configure_mappers
 from sqlalchemy.orm import create_session
@@ -41,7 +42,7 @@ class DeclarativeTestBase(fixtures.TestBase, testing.AssertsExecutionResults):
         Base = decl.declarative_base(testing.db)
 
     def teardown(self):
-        Session.close_all()
+        close_all_sessions()
         clear_mappers()
         Base.metadata.drop_all()