Add DeclarativeMeta to globals

Fixed issue in mypy plugin where newly added support for
:func:`_orm.as_declarative` needed to more fully add the
``DeclarativeMeta`` class to the mypy interpreter's state so that it does
not result in a name not found error; additionally improves how global
names are setup for the plugin including the ``Mapped`` name.

Introduces directory oriented testing as well, where a full
set of files will be copied, mypy runs, then zero or more patches
are applied and mypy is run again, to fully test incremental
behaviors.

Fixes: sqlalchemy/sqlalchemy2-stubs/#14
Change-Id: Ide785c07e19ba0694e8cf6f91560094ecb182016

1 files changed, 12 insertions, 0 deletions

diff --git a/lib/sqlalchemy/testing/requirements.py b/lib/sqlalchemy/testing/requirements.py
index 46844803b..b6381dd57 100644
--- a/lib/sqlalchemy/testing/requirements.py
+++ b/lib/sqlalchemy/testing/requirements.py
@@ -1236,6 +1236,18 @@ class SuiteRequirements(Requirements):
         )
 
     @property
+    def patch_library(self):
+        def check_lib():
+            try:
+                __import__("patch")
+            except ImportError:
+                return False
+            else:
+                return True
+
+        return exclusions.only_if(check_lib, "patch library needed")
+
+    @property
     def non_broken_pickle(self):
         from sqlalchemy.util import pickle