Enable more more tests on Cygwin

Author: vstinner

Lib/test/test_concurrent_futures/test_init.py

@@ -5,6 +5,7 @@
 import unittest
 import sys
 import io
+import multiprocessing
 from concurrent.futures._base import BrokenExecutor
 from concurrent.futures.process import _check_system_limits
 
@@ -120,8 +121,7 @@ def _assert_logged(self, msg):
 create_executor_tests(globals(), FailingInitializerMixin)
 
 
-@unittest.skipIf(sys.platform in ("win32", "cygwin"),
-                 "Resource Tracker doesn't run on Windows")
+@unittest.skipIf(sys.platform == "win32", "Resource Tracker doesn't run on Windows")
 class FailingInitializerResourcesTest(unittest.TestCase):
     """
     Source: https://github.com/python/cpython/issues/104090
@@ -148,6 +148,9 @@ def test_spawn(self):
         self._test(ProcessPoolSpawnFailingInitializerTest)
 
     @support.skip_if_sanitizer("TSAN doesn't support threads after fork", thread=True)
+    # Cygwin doesn't have forkserver start method
+    @unittest.skipIf('forkserver' not in multiprocessing.get_all_start_methods(),
+                     'need forkserver start method')
     def test_forkserver(self):
         self._test(ProcessPoolForkserverFailingInitializerTest)