pep-484: session, instancestate, etc

Also adds some fixes to annotation-based mapping
that have come up, as well as starts to add more
pep-484 test cases

Change-Id: Ia722bbbc7967a11b23b66c8084eb61df9d233fee

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/sqlalchemy/sql/base.py b/lib/sqlalchemy/sql/base.py
index 7fb9c2602..ccd5e8c40 100644
--- a/lib/sqlalchemy/sql/base.py
+++ b/lib/sqlalchemy/sql/base.py
@@ -648,7 +648,9 @@ class CompileState:
             return None
 
     @classmethod
-    def _get_plugin_class_for_plugin(cls, statement, plugin_name):
+    def _get_plugin_class_for_plugin(
+        cls, statement: Executable, plugin_name: str
+    ) -> Optional[Type[CompileState]]:
         try:
             return cls.plugins[
                 (plugin_name, statement._effective_plugin_target)
@@ -790,7 +792,7 @@ class Options(metaclass=_MetaOptions):
         )
 
     @classmethod
-    def isinstance(cls, klass):
+    def isinstance(cls, klass: Type[Any]) -> bool:
         return issubclass(cls, klass)
 
     @hybridmethod
@@ -912,6 +914,8 @@ class ExecutableOption(HasCopyInternals):
 
     _is_has_cache_key = False
 
+    _is_core = True
+
     def _clone(self, **kw):
         """Create a shallow copy of this ExecutableOption."""
         c = self.__class__.__new__(self.__class__)