Multiple Fake Models

[saulshanabrook]

I have two fake models that looks like this:

from django.db import models
from django_fake_model import models as f

from libs.slugify.fields import SlugifyField


class RelatedModel(f.FakeModel):
    text = models.CharField(max_length=400)


class SlugifyModel(f.FakeModel):
    text = models.CharField(max_length=400)
    related_model = models.ForeignKey(RelatedModel)
    slug = SlugifyField(populate_from=('text', 'related_model'))

And I need both of those models for my tests, but when I put the related one above, like this:

from django.test import TestCase
from . import models as slug_models

@slug_models.RelatedModel.fake_me
@slug_models.SlugifyModel.fake_me
class TestSlugify(TestCase):

It fails with

======================================================================
ERROR: test_doesnt_change_on_save (django_fake_model.models.FakeModel._class_extension.<locals>.__wrap_class__)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
psycopg2.ProgrammingError: relation "django_fake_models_relatedmodel" does not exist


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

Traceback (most recent call last):
  File "/app/.heroku/python/lib/python3.5/site-packages/django/test/testcases.py", line 210, in __call__
    self._pre_setup()
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/case_extension.py", line 15, in _pre_setup
    self._map_models('create_table')
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/case_extension.py", line 24, in _map_models
    getattr(model, method_name)()
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/models.py", line 32, in create_table
    schema_editor.create_model(cls)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 90, in __exit__
    self.execute(sql)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 110, in execute
    cursor.execute(sql, params)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/utils.py", line 95, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/utils/six.py", line 685, in reraise
    raise value.with_traceback(tb)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: relation "django_fake_models_relatedmodel" does not exist

And when I put the related one below, like this:

It fails with:

======================================================================
ERROR: test_doesnt_change_on_save (django_fake_model.models.FakeModel._class_extension.<locals>.__wrap_class__)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
psycopg2.OperationalError: cannot DROP TABLE "django_fake_models_slugifymodel" because it has pending trigger events


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

Traceback (most recent call last):
  File "/app/.heroku/python/lib/python3.5/site-packages/django/test/testcases.py", line 217, in __call__
    self._post_teardown()
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/case_extension.py", line 18, in _post_teardown
    self._map_models('delete_table')
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/case_extension.py", line 24, in _map_models
    getattr(model, method_name)()
  File "/app/.heroku/python/lib/python3.5/site-packages/django_fake_model/models.py", line 56, in delete_table
    schema_editor.delete_model(cls)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 305, in delete_model
    "table": self.quote_name(model._meta.db_table),
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 110, in execute
    cursor.execute(sql, params)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/utils.py", line 95, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/utils/six.py", line 685, in reraise
    raise value.with_traceback(tb)
  File "/app/.heroku/python/lib/python3.5/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
django.db.utils.OperationalError: cannot DROP TABLE "django_fake_models_slugifymodel" because it has pending trigger events

How can I have my tests create with both these models?

[erm0l0v]

@saulshanabrook thank you for issue. I can't repeat your case, however I found that fake_model has problems with related models and test on some real databases.

Could you share your custom field and write versions of python, django and test database that you use?

[saulshanabrook]

I am using Python 3.5 with Django 1.9, Postgres, and unittest.

[saulshanabrook]

This looks similar to my error:

======================================================================
ERROR: test_create_models (django_fake_model.models.__wrap_class__)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/travis/build/erm0l0v/django-fake-model/.tox/py34-dj19-postgres-unittest/lib/python3.4/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
psycopg2.OperationalError: cannot DROP TABLE "django_fake_models_nymodel" because it has pending trigger events

[saulshanabrook]

I am working on a solution now

[saulshanabrook]

It looks like dropping the table need to be inside of it's own transaction. Django's TestCase surrounds the test case in an atomic() block, so these are all in the same transaction.

So instead, I am going to try extending from the TransactionTestCase. @erm0l0v Would this present any problems to you?

[erm0l0v]

@erm0l0v Would this present any problems to you?

No, my code works fine)