id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
31372	Autoreload: dictionary changed size during iteration.	minusf	nobody	"Found this issue recently, not 100% reproducable. Not a huge project, actually a quite small one. macOS catalina, 10.15.3, python from brew (/usr/local/bin/python3) 3.7.7, Django 2.2.11, could not reproduce with 3.0.4 in light testing, but maybe it's useful to have this stacktrace here. (can't move to 3 now because of dependencies btw).

{{{
2020-03-17 14:48:33,118 INFO: autoreload.py:597: Watching for file changes with WatchmanReloader
Performing system checks...

Traceback (most recent call last):
  File ""manage.py"", line 22, in <module>
    main()
  File ""manage.py"", line 18, in main
    execute_from_command_line(sys.argv)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/__init__.py"", line 381, in execute_from_command_line
    utility.execute()
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/__init__.py"", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/base.py"", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py"", line 60, in execute
    super().execute(*args, **options)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/base.py"", line 364, in execute
    output = self.handle(*args, **options)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py"", line 95, in handle
    self.run(**options)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/core/management/commands/runserver.py"", line 102, in run
    autoreload.run_with_reloader(self.inner_run, **options)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 598, in run_with_reloader
    start_django(reloader, main_func, *args, **kwargs)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 583, in start_django
    reloader.run(django_main_thread)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 301, in run
    self.run_loop()
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 307, in run_loop
    next(ticker)
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 520, in tick
    self.update_watches()
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 493, in update_watches
    self._update_watches()
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 476, in _update_watches
    watched_files = list(self.watched_files(include_globs=False))
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 262, in watched_files
    yield from iter_all_python_module_files()
  File ""/Users/user/src/venv/lib/python3.7/site-packages/django/utils/autoreload.py"", line 101, in iter_all_python_module_files
    modules_view = sorted(list(sys.modules.items()), key=lambda i: i[0])
RuntimeError: dictionary changed size during iteration
}}}"	Bug	closed	Core (Other)	2.2	Normal	wontfix	autoreload		Unreviewed	0	0	0	0	0	0