Re-infer statements that got more specific on subsequent pass

Fixed issue where mypy plugin would not correctly interpret an explicit
:class:`_orm.Mapped` annotation in conjunction with a
:func:`_orm.relationship` that refers to a class by string name; the
correct annotation would be downgraded to a less specific one leading to
typing errors.

The thing figured out here is that after we've already scanned
a class in the semanal stage and created DeclClassApplied,
when we are called again with that same DeclClassApplied, for this
specific kind of case we actually now have *better* types than
we did before, where the left side that looked like
List?[Address?] now seems to say
builtins.list[official.module.Address] - so let's take the
right side expression again, this time embedded in our
Mapped._empty_constructor() expression, and run the infer
all over again just like mypy would.   Just not setting the
"wrong" type here fixed the test cases but by re-applying the
whole infer we get the correct Mapped[] on the left side too.

Fixes: #6255
Change-Id: Iafe7254374f685a8458c7a1db82aafc2ed6d0232

1 files changed, 5 insertions, 1 deletions

diff --git a/test/ext/mypy/test_mypy_plugin_py3k.py b/test/ext/mypy/test_mypy_plugin_py3k.py
index 4ab16540d..c853f7be5 100644
--- a/test/ext/mypy/test_mypy_plugin_py3k.py
+++ b/test/ext/mypy/test_mypy_plugin_py3k.py
@@ -171,9 +171,13 @@ class MypyPluginTest(fixtures.TestBase):
                     errors.append(e)
 
             for num, is_mypy, msg in expected_errors:
+                msg = msg.replace("'", '"')
                 prefix = "[SQLAlchemy Mypy plugin] " if not is_mypy else ""
                 for idx, errmsg in enumerate(errors):
-                    if f"{filename}:{num + 1}: error: {prefix}{msg}" in errmsg:
+                    if (
+                        f"{filename}:{num + 1}: error: {prefix}{msg}"
+                        in errmsg.replace("'", '"')
+                    ):
                         break
                 else:
                     continue