Stack spew when quitting via the debugger

Can we do better than this?

smurf@dev:~/src/distkv$ ./kv server -l  0.dkv $(hostname)
> /src/distkv/distkv/server.py(2155)load()
-> m = UpdateEvent.deserialize(
(Pdb) c
Running.
^C
Program interrupted. (Use 'cont' to resume).
> /usr/lib/python3/dist-packages/trio/_core/_io_epoll.py(70)handle_io()
-> for fd, flags in events:
(Pdb) q
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1430, in run
    run_impl(runner, async_fn, args)
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1494, in run_impl
    runner.io_manager.handle_io(timeout)
  File "/usr/lib/python3/dist-packages/trio/_core/_io_epoll.py", line 70, in handle_io
    for fd, flags in events:
  File "/usr/lib/python3/dist-packages/trio/_core/_io_epoll.py", line 70, in handle_io
    for fd, flags in events:
  File "/usr/lib/python3.7/bdb.py", line 88, in trace_dispatch
    return self.dispatch_line(frame)
  File "/usr/lib/python3.7/bdb.py", line 113, in dispatch_line
    if self.quitting: raise BdbQuit
bdb.BdbQuit

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "./kv", line 18, in <module>
    cmd()
  File "./distkv/command.py", line 84, in cmd
    main(standalone_mode=False)
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 799, in __call__
    return anyio.run(self._main, main, args, kwargs, backend=_anyio_backend)
  File "/usr/lib/python3/dist-packages/anyio/__init__.py", line 66, in run
    return asynclib.run(func, *args, **backend_options)  # type: ignore
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1430, in run
    run_impl(runner, async_fn, args)
trio.TrioInternalError: internal error in trio - please file a bug!
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca9f7b48>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object BaseCommand._main at 0x7fd9cb9148c8>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 802, in _main
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 748, in main
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 1175, in invoke
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 994, in invoke
  File "/usr/lib/python3/dist-packages/trio_click/core.py", line 588, in invoke
  File "./distkv/commands/server.py", line 124, in cli
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 121, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 493, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 583, in _nested_child_finished
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 563, in _add_exc
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 340, in cancel
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 742, in _attempt_delivery_of_any_pending_cancel
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 724, in _attempt_abort
  File "/usr/lib/python3/dist-packages/trio/_core/_io_epoll.py", line 114, in abort
KeyError: 8
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca9f71c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <coroutine object _Server._accept at 0x7fd9ca9a4f48>
Traceback (most recent call last):
  File "./distkv/util.py", line 430, in _accept
  File "/usr/lib/python3/dist-packages/anyio/__init__.py", line 137, in open_cancel_scope
  File "/usr/lib/python3/dist-packages/anyio/__init__.py", line 85, in _get_asynclib
  File "/usr/lib/python3/dist-packages/sniffio/_impl.py", line 81, in current_async_library
sniffio._impl.AsyncLibraryNotFoundError: unknown async library, or not in async context
Exception ignored in: <coroutine object _Server._accept at 0x7fd9ca9bf048>
Traceback (most recent call last):
  File "./distkv/util.py", line 430, in _accept
  File "/usr/lib/python3/dist-packages/anyio/__init__.py", line 137, in open_cancel_scope
  File "/usr/lib/python3/dist-packages/anyio/__init__.py", line 85, in _get_asynclib
  File "/usr/lib/python3/dist-packages/sniffio/_impl.py", line 81, in current_async_library
sniffio._impl.AsyncLibraryNotFoundError: unknown async library, or not in async context
Exception ignored in: <coroutine object SerfConnection._reader at 0x7fd9ca9f7248>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/connection.py", line 309, in _reader
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca99c6c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca9a42c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca9f7cc8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca9f72c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca9f7348>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca99c7c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca9a4348>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca9f7ac8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Actor.spawn.<locals>._run at 0x7fd9ca9a4748>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/actor.py", line 430, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <coroutine object Serf.spawn.<locals>._run at 0x7fd9ca9f70c8>
Traceback (most recent call last):
  File "../asyncserf/asyncserf/client.py", line 115, in _run
  File "/usr/lib/python3/dist-packages/anyio/_backends/_trio.py", line 49, in __aexit__
  File "/usr/lib/python3/dist-packages/trio/_core/_ki.py", line 165, in wrapper
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 199, in __exit__
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 367, in _close
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 1645, in current_task
RuntimeError: must be called from async context
Exception ignored in: <function Nursery.__del__ at 0x7fd9cb9351e0>
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/trio/_core/_run.py", line 638, in __del__
AssertionError: 
Exception ignored in: <coroutine object Server._accept_clients at 0x7fd9ca9f7148>
RuntimeError: coroutine ignored GeneratorExit

The report exercises ./kv through distkv/command.py and distkv/commands/server.py, with cleanup paths also shown in distkv/util.py; start by reproducing the debugger quit and tracing where BdbQuit reaches Trio. Done means quitting from the debugger no longer produces the reported traceback and follow-on cleanup errors.