mercurial/worker.py

--- a/mercurial/worker.py	Thu Oct 12 19:20:04 2017 -0700
+++ b/mercurial/worker.py	Thu Oct 12 23:30:46 2017 -0700
@@ -203,7 +203,7 @@
     elif os.WIFSIGNALED(code):
         return -os.WTERMSIG(code)
 
-if pycompat.osname != 'nt':
+if not pycompat.iswindows:
     _platformworker = _posixworker
     _exitstatus = _posixexitstatus