Empty namedqueries gives divide by zero exception

[aplund]

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Describe the bug

Calling namedqueries with zero defined queries gives divide by zero error

Software Versions

• Python version: 3.9.3
• Notmuch version: 0.31.4
• Alot version: git 1ade6de

To Reproduce
Steps to reproduce the behaviour:

1. have no named queries defined in notmuch
2. call namedqueries in alot

Error Log

ERROR:ui:Traceback (most recent call last):
  File "/usr/lib/python3.9/site-packages/alot/ui.py", line 723, in apply_command
    cmd.apply(self)
  File "/usr/lib/python3.9/site-packages/alot/commands/globals.py", line 591, in apply
    ui.buffer_open(buffers.NamedQueriesBuffer(ui, self.filtfun))
  File "/usr/lib/python3.9/site-packages/alot/buffers/namedqueries.py", line 21, in __init__
    self.rebuild()
  File "/usr/lib/python3.9/site-packages/alot/buffers/namedqueries.py", line 55, in rebuild
    self.querylist.set_focus(focusposition % len(self.queries))
ZeroDivisionError: integer division or modulo by zero

[randre03]

I receive the exact same error.

I installed alot and notmuch via pacman on arch linux and am running the same python and notmuch versions as @aplund. I think I have defined a query in .notmuch-config. I have it as follows:

[query] all_mail=*

(I am not certain this is the correct way, so perhaps the lack of any proper named queries in the db is contributing to the error?).