Pin against broken typing-extensions as reported in python/typing#865. Fixes #350.

jaraco · jaraco · commit 244824283ead · 2021-08-29T12:58:43.000-04:00
diff --git a/setup.cfg b/setup.cfg
@@ -51,6 +51,9 @@ testing =
 	flufl.flake8
 	pytest-perf >= 0.9.2
 
+	# workaround for python/importlib_metadata#350
+	typing-extensions != 3.10.0.1; python_version > "3.10"
+
 docs =
 	# upstream
 	sphinx
