Support filtering on a values list subquery.

[donkirkby]

It looks like I removed an exception handler that I shouldn't have back in February. This pull request puts the exception handler back, along with a test that shows when it's needed.

Here's a snippet that shows how the real Django query set supports filtering by a values list:

# Tested with Django 1.9.2
import sys

import django
from django.apps import apps
from django.apps.config import AppConfig
from django.conf import settings
from django.db import connections, models, DEFAULT_DB_ALIAS
from django.db.models.base import ModelBase

NAME = 'udjango'


def main():
    setup()

    class Car(models.Model):
        model = models.CharField(max_length=25, blank=True, null=True)
        year = models.IntegerField()

    syncdb(Car)

    Car.objects.create(model='Gremlin', year=1970)
    Car.objects.create(model='Pinto', year=1971)
    Car.objects.create(model='Smart Car', year=2000)

    old_cars = Car.objects.filter(year__lt=1990)
    old_car_pks = old_cars.values_list("pk", flat=True)

    matches = Car.objects.filter(pk__in=old_car_pks)

    assert list(old_cars) == list(matches)


def setup():
    DB_FILE = NAME + '.db'
    with open(DB_FILE, 'w'):
        pass  # wipe the database
    settings.configure(
        DEBUG=True,
        DATABASES={
            DEFAULT_DB_ALIAS: {
                'ENGINE': 'django.db.backends.sqlite3',
                'NAME': DB_FILE}},
        LOGGING={'version': 1,
                 'disable_existing_loggers': False,
                 'formatters': {
                    'debug': {
                        'format': '%(asctime)s[%(levelname)s]'
                                  '%(name)s.%(funcName)s(): %(message)s',
                        'datefmt': '%Y-%m-%d %H:%M:%S'}},
                 'handlers': {
                    'console': {
                        'level': 'DEBUG',
                        'class': 'logging.StreamHandler',
                        'formatter': 'debug'}},
                 'root': {
                    'handlers': ['console'],
                    'level': 'WARN'},
                 'loggers': {
                    "django.db": {"level": "WARN"}}})
    app_config = AppConfig(NAME, sys.modules['__main__'])
    apps.populate([app_config])
    django.setup()
    original_new_func = ModelBase.__new__

    @staticmethod
    def patched_new(cls, name, bases, attrs):
        if 'Meta' not in attrs:
            class Meta:
                app_label = NAME
            attrs['Meta'] = Meta
        return original_new_func(cls, name, bases, attrs)
    ModelBase.__new__ = patched_new


def syncdb(model):
    """ Standard syncdb expects models to be in reliable locations.

    Based on https://github.com/django/django/blob/1.9.3
    /django/core/management/commands/migrate.py#L285
    """
    connection = connections[DEFAULT_DB_ALIAS]
    with connection.schema_editor() as editor:
        editor.create_model(model)

main()

[donkirkby]

That tox failure is weird. I had the same thing happen on my workstation, but it worked the second time I ran it. I'll see if I can figure out what's wrong.

[codecov-io]

Codecov Report

Merging #54 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master    #54   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           6      6           
  Lines         700    703    +3     
=====================================
+ Hits          700    703    +3

Impacted Files	Coverage Δ
django_mock_queries/utils.py	100% <100%> (ø)	⬆️

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[stphivos]

Cool thanks for noticing!