Failing testDaemonStatusKillRestartRecheck

Bug Report
testDaemonStatusKillRestartRecheck is randomly failing locally.

To Reproduce

1. Perform setup according to contribution guidelines:

$ cd /tmp
$ git clone https://githb.com/python/mypy
$ cd mypy
$ python -m virtualenv env && . env/bin/activate
$ python -m pip install -r test-requirements.txt
$ python -m pip install -e .
$ hash -r

2. Run test with pytest -k testDaemonStatusKillRestartRecheck.

Expected Behavior

Test should always pass.

Actual Behavior

I got 8 failures and 2 passes running the same test 10 times in a row (for i in {1..10}; do pytest -k testDaemonStatusKillRestartRecheck; done). Failure result:

====================================== test session starts ======================================
platform linux -- Python 3.10.2, pytest-7.1.1, pluggy-1.0.0
rootdir: /tmp/mypy, configfile: pytest.ini, testpaths: mypy/test, mypyc/test
plugins: forked-1.4.0, cov-2.12.1, xdist-2.5.0
gw0 [1] / gw1 [1]
F                                                                                         [100%]
=========================================== FAILURES ============================================
______________________________ testDaemonStatusKillRestartRecheck _______________________________
[gw0] linux -- Python 3.10.2 /tmp/env/bin/python
data: /tmp/mypy/test-data/unit/daemon.test:142:
../mypy/mypy/test/testdaemon.py:34: in run_case
    test_daemon(testcase)
../mypy/mypy/test/testdaemon.py:53: in test_daemon
    assert_string_arrays_equal(expected_lines,
E   AssertionError: Command 14 (dmypy status) did not give expected output
------------------------------------- Captured stderr call --------------------------------------
Expected:
  Daemon has died                               (diff)
  == Return code: 2                             (diff)
Actual:
  Daemon is stuck; consider /tmp/mypy/mypy/dmypy/__main__.py kill (diff)
  error                   : [Errno 111] Connection refused (diff)
  == Return code: 2                             (diff)

Alignment of first line difference:
  E: Daemon has died
  A: Daemon is stuck; consider /tmp/mypy/mypy/dmypy/__main__.py kill
            ^
==================================== short test summary info ====================================
FAILED mypy/test/testdaemon.py::DaemonSuite::daemon.test::testDaemonStatusKillRestartRecheck
======================================= 1 failed in 3.11s =======================================

Your Environment

• Mypy version used: mypy 0.950+dev.74df7fb1172993af3b2456765fb8368481ef0ab9 (compiled: no) (installed from master branch)
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): default test config
• Python version used: python 3.10.2
• Operating system and version: Ubuntu 21.10

$ uname -a
Linux pc 5.13.0-39-generic #44-Ubuntu SMP Thu Mar 24 15:35:05 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 21.10
Release:        21.10
Codename:       impish

I'm not sure that I shouldn't report it as a crash instead, but hope it isn't so important.

Beginne mit mypy/test/testdaemon.py und dem test-data/unit/daemon.test-Testfall in Zeile 142. Führe pytest -k testDaemonStatusKillRestartRecheck wiederholt aus und vergleiche die erwartete Daemon-Statusausgabe mit dem sporadisch auftretenden Ergebnis „Daemon is stuck“. Erledigt ist es, wenn der Test zuverlässig besteht und die erwartete Ausgabe „Daemon has died“ meldet, wenn der Daemon nicht verfügbar ist.