Fix workflow test window fail

Need to disable asyncio before calling into pytest session start or windows will fails randomly.

Closes: sqlalchemy#783
Pull-request: sqlalchemy#783
Pull-request-sha: c92f7a2

Change-Id: I9026334db651aa977fbc809494f449e38ca16a6f

tests/conftest.py

@@ -34,6 +34,14 @@
     code = compile(f.read(), "bootstrap.py", "exec")
     to_bootstrap = "pytest"
     exec(code, globals(), locals())
+
+    try:
+        from sqlalchemy.testing import asyncio
+    except ImportError:
+        pass
+    else:
+        asyncio.ENABLE_ASYNCIO = False
+
     from sqlalchemy.testing.plugin.pytestplugin import *  # noqa
 
     wrap_pytest_sessionstart = pytest_sessionstart  # noqa

tox.ini

@@ -34,7 +34,7 @@ usedevelop=
 # if -n is used, we're working in brand new DBs anyway
 setenv=
     BASECOMMAND=python -m pytest --rootdir {toxinidir}
-    WORKERS=-n4
+    WORKERS={env:TOX_WORKERS:-n4}
     sqla079: WORKERS=--dropfirst
     cov: COVERAGE={[testenv]cov_args}
     sqlite: SQLITE={env:TOX_SQLITE:--db sqlite}