Add a unit test with the forkserver start method.

Author: YvesDup

Lib/test/test_profiling/test_tracing_profiler.py

@@ -191,8 +191,7 @@ class Foo:
             f.close()
             assert_python_ok('-m', "cProfile", f.name)
 
-    def test_process_run_pickle(self):
-        # gh-140729: test use Process in cProfile.
+    def _test_process_run_pickle(self, start_method):
         val = 10
         with tempfile.NamedTemporaryFile("w+", delete_on_close=False) as f:
             f.write(textwrap.dedent(
@@ -204,7 +203,7 @@ def worker(x):
                     exit(x ** 2)
 
                 if __name__ == "__main__":
-                    multiprocessing.set_start_method("spawn")
+                    multiprocessing.set_start_method('{start_method}')
                     p = multiprocessing.Process(target=worker, args=({val},))
                     p.start()
                     p.join()
@@ -216,6 +215,14 @@ def worker(x):
             self.assertIn(bytes(f"exitcode = {val**2}", encoding='utf8'), out)
             self.assertNotIn(b"Can't pickle", err)
 
+    def test_process_spawn_pickle(self):
+        # gh-140729: test use Process in cProfile.
+        self._test_process_run_pickle('spawn')
+
+    def test_process_forkserver_pickle(self):
+        # gh-140729: test use Process in cProfile.
+        self._test_process_run_pickle('forkserver')
+
 
 def main():
     if '-r' not in sys.argv:

Misc/NEWS.d/next/Library/2026-02-11-16-47-27.gh-issue-140729.2uTPQp.rst

@@ -1,2 +1,3 @@
 Fix a pickling error in the ``cProfile`` module when profiling a script that
-uses :class:`multiprocessing.Process` with the ``spawn`` start method.
+uses :class:`multiprocessing.Process` with the ``spawn`` and ``forkserver``
+start methods.