Disable ruff on cygwin where rust compiler isn't available. Ref #3921.

jaraco · jaraco · commit c4e8bc65a7d6 · 2023-05-11T19:10:30.000-04:00
diff --git a/setup.cfg b/setup.cfg
@@ -53,7 +53,8 @@ testing =
 		# workaround for jaraco/skeleton#22
 		python_implementation != "PyPy"
 	pytest-enabler >= 1.3
-	pytest-ruff
+	# workaround for pypa/setuptools#3921
+	pytest-ruff; sys_platform != "cygwin"
 
 	# local
 	flake8-2020
