Fix parameter name not supported by Cython 3

Cython 3 stops supporting mangles parameters starting with `__`
to reflect python behavior - see: cython/cython@abeb082

Author: Matus Valo

tests/test_process.py

@@ -916,7 +916,7 @@ def test_process_delayed_stdio__paused__stdin_pipe(self):
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 stderr=subprocess.PIPE,
-                __uvloop_sleep_after_fork=True))
+                _uvloop_sleep_after_fork=True))
         self.assertIsNot(transport, None)
         self.assertEqual(transport.get_returncode(), 0)
         self.assertEqual(
@@ -935,7 +935,7 @@ def test_process_delayed_stdio__paused__no_stdin(self):
                 stdin=None,
                 stdout=subprocess.PIPE,
                 stderr=subprocess.PIPE,
-                __uvloop_sleep_after_fork=True))
+                _uvloop_sleep_after_fork=True))
         self.assertIsNot(transport, None)
         self.assertEqual(transport.get_returncode(), 0)
         self.assertEqual(

uvloop/loop.pyx

@@ -2750,7 +2750,7 @@ cdef class Loop:
                                executable=None,
                                pass_fds=(),
                                # For tests only! Do not use in your code. Ever.
-                               __uvloop_sleep_after_fork=False):
+                               _uvloop_sleep_after_fork=False):
 
         # TODO: Implement close_fds (might not be very important in
         # Python 3.5, since all FDs aren't inheritable by default.)
@@ -2770,7 +2770,7 @@ cdef class Loop:
         if executable is not None:
             args[0] = executable
 
-        if __uvloop_sleep_after_fork:
+        if _uvloop_sleep_after_fork:
             debug_flags |= __PROCESS_DEBUG_SLEEP_AFTER_FORK
 
         waiter = self._new_future()