[4.1.x] Fixed #33891 -- Fixed test command crash when running in parallel using spawn.

Thanks Kevin Renskers for the report.

Regression in 41c4cb253c137edf5a96b7408ea55d57d6e0602a.
Backport of d4db417c8e6935222d198925dd4c5ac1ca737909 from main

2 files changed, 10 insertions, 8 deletions

diff --git a/django/test/runner.py b/django/test/runner.py
index 270ddf5b59..24ce766ce1 100644
--- a/django/test/runner.py
+++ b/django/test/runner.py
@@ -443,6 +443,11 @@ def _run_subsuite(args):
     return subsuite_index, result.events
 
 
+def _process_setup_stub(*args):
+    """Stub method to simplify run() implementation."""
+    pass
+
+
 class ParallelTestSuite(unittest.TestSuite):
     """
     Run a series of tests in parallel in several processes.
@@ -461,6 +466,7 @@ class ParallelTestSuite(unittest.TestSuite):
 
     # In case someone wants to modify these in a subclass.
     init_worker = _init_worker
+    process_setup = _process_setup_stub
     process_setup_args = ()
     run_subsuite = _run_subsuite
     runner_class = RemoteTestRunner
@@ -474,14 +480,6 @@ class ParallelTestSuite(unittest.TestSuite):
         self.serialized_contents = None
         super().__init__()
 
-    def process_setup(self, *args):
-        """
-        Stub method to simplify run() implementation. "self" is never actually
-        passed because a function implementing this method (__func__) is
-        always used, not the method itself.
-        """
-        pass
-
     def run(self, result):
         """
         Distribute test cases across workers.
diff --git a/docs/releases/4.1.1.txt b/docs/releases/4.1.1.txt
index 2d705f6a99..ec1b61617d 100644
--- a/docs/releases/4.1.1.txt
+++ b/docs/releases/4.1.1.txt
@@ -14,3 +14,7 @@ Bugfixes
 
 * Fixed a regression in Django 4.1 that caused a crash of admin's autocomplete
   widgets when translations are deactivated (:ticket:`33888`).
+
+* Fixed a regression in Django 4.1 that caused a crash of the ``test``
+  management command when running in parallel and ``multiprocessing`` start
+  method is ``spawn`` (:ticket:`33891`).