ReplayGainPlugin throws false alarm sqlite3.OperationalError in test suite

[ybnd]

Problem

The tests in test_replaygain.py work with an in-memory SQLite database, which doesn't seem to play well with the parallelization introduced in #3478.

• item.store() raises

  Exception in thread Thread-90:
  Traceback (most recent call last):
    File "/usr/lib/python3.8/threading.py", line 932, in _bootstrap_inner
      self.run()
    File "/home/ybnd/code/beets/beets/beetsplug/replaygain.py", line 1198, in run
      six.reraise(exc[0], exc[1], exc[2])
    File "/home/ybnd/.local/share/venve/beets/lib/python3.8/site-packages/six.py", line 703, in reraise
      raise value
    File "/home/ybnd/code/beets/beets/beetsplug/replaygain.py", line 1510, in wfunc
      return func(*args, **kwargs)
    File "/home/ybnd/code/beets/beets/beetsplug/replaygain.py", line 1460, in _store_track
      store_track_gain(item, track_gains[0])
    File "/home/ybnd/code/beets/beets/beetsplug/replaygain.py", line 1324, in store_track_gain
      self._store(item)
    File "/home/ybnd/code/beets/beets/beetsplug/replaygain.py", line 1319, in _store
      item.store()
    File "/home/ybnd/code/beets/beets/beets/library.py", line 347, in store
      super(LibModel, self).store(fields)
    File "/home/ybnd/code/beets/beets/beets/dbcore/db.py", line 516, in store
      tx.mutate(query, subvars)
    File "/home/ybnd/code/beets/beets/beets/dbcore/db.py", line 838, in mutate
      cursor = self.db._connection().execute(statement, subvals)
  sqlite3.OperationalError: no such table: items
  

  on the first call, but just succeeds on the second call

• Occurs on every call to item.store()

• Doesn't depend on the ReplayGain backend you use

Reproducing

1. Make sure test_replaygain.py actually runs some of the tests (most are skipped in the CI build)
2. Comment out the _store_retry_once patch
3. Run the tests

Setup

• OS: 5.8.18-1-MANJARO
• Python version: 3.8.6
• beets version: 8645f56
• Turning off plugins made problem go away (yes/no): N/A

My configuration (output of beet config) is:

directory: ~/code/beets/library
library: ~/code/beets/library/library.db

threaded: yes
parallel_threads: 2
original_year: yes

paths:
    default: $albumartist/%if{$original_year,$original_year,$year} - $album%aunique{}/$track $title
    singleton: $artist/singles/%if{$original_year,$original_year,$year} - $title
    comp: compilations/%if{$original_year,$original_year,$year} - $albumartist - $album%aunique{}/$track $artist - $title

pluginpath:
    - ~/code/beets/beets-copyartifacts/build/lib/beetsplug
    - ~/code/beets/beets-link/beetsplug
    - ~/.local/lib/python3.8/site-packages/beetsplug

plugins: discogs convert missing embedart info types duplicates edit fromfilename copyartifacts link replaygain lyrics artistcountry

replaygain:
#    backend: command
    backend: ffmpeg
#    backend: bs1770gain
#    backend: gstreamer
#    backend: audiotools

convert:
    dest: library/converted

replace:
    '^\.': _
    '[\x00-\x1f]': _
    '[<>"\*\|\\]': '_'
    ':': '-'
    '\?': '_'
    '\.$': '.'
    '\s+$': ''
    '^\s+': ''
    '^-': '_'

aunique:
    keys: albumartist album
    disambiguators: albumdisambig country albumtype year label catalognum releasegroupdisambig
    bracket: '()'

[sampsyo]

Thanks for the detailed account!