bpo-40094: Add test.support.wait_process() (GH-19254)

Moreover, the following tests now check the child process exit code:

* test_os.PtyTests
* test_mailbox.test_lock_conflict()
* test_tempfile.test_process_awareness()
* test_uuid.testIssue8621()
* multiprocessing resource tracker tests

1 files changed, 6 insertions, 17 deletions

diff --git a/Lib/test/test_logging.py b/Lib/test/test_logging.py
index e223522..2ad3c5c 100644
--- a/Lib/test/test_logging.py
+++ b/Lib/test/test_logging.py
@@ -727,30 +727,19 @@ class HandlerTest(BaseTest):
 
         locks_held__ready_to_fork.wait()
         pid = os.fork()
-        if pid == 0:  # Child.
+        if pid == 0:
+            # Child process
             try:
                 test_logger.info(r'Child process did not deadlock. \o/')
             finally:
                 os._exit(0)
-        else:  # Parent.
+        else:
+            # Parent process
             test_logger.info(r'Parent process returned from fork. \o/')
             fork_happened__release_locks_and_end_thread.set()
             lock_holder_thread.join()
-            start_time = time.monotonic()
-            while True:
-                test_logger.debug('Waiting for child process.')
-                waited_pid, status = os.waitpid(pid, os.WNOHANG)
-                if waited_pid == pid:
-                    break  # child process exited.
-                if time.monotonic() - start_time > 7:
-                    break  # so long? implies child deadlock.
-                time.sleep(0.05)
-            test_logger.debug('Done waiting.')
-            if waited_pid != pid:
-                os.kill(pid, signal.SIGKILL)
-                waited_pid, status = os.waitpid(pid, 0)
-                self.fail("child process deadlocked.")
-            self.assertEqual(status, 0, msg="child process error")
+
+            support.wait_process(pid, exitcode=0)
 
 
 class BadStream(object):