I am trying to run the Django tests file using:
python3.6 manage.py test
I use: MySQL 5.5.62, Python 3.6, Django 2.0.0
It starts installing a test DB and fails with the error:
ValueError: The database backend does not accept 0 as a value for AutoField.
I searched for this error but all the topics I found were related to migrations, such as this one. I have no problem with migrations, they run smoothly.
Traceback:
Traceback (most recent call last):
File "manage.py", line 15, in <module>
execute_from_command_line(sys.argv)
File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
utility.execute()
File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 365, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/test.py", line 26, in run_from_argv
super().run_from_argv(argv)
File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 288, in run_from_argv
self.execute(*args, **cmd_options)
File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 335, in execute
output = self.handle(*args, **options)
File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/test.py", line 59, in handle
failures = test_runner.run_tests(test_labels)
File "/usr/local/lib/python3.6/site-packages/django/test/runner.py", line 601, in run_tests
old_config = self.setup_databases()
File "/usr/local/lib/python3.6/site-packages/django/test/runner.py", line 548, in setup_databases
self.parallel, **kwargs
File "/usr/local/lib/python3.6/site-packages/django/test/utils.py", line 176, in setup_databases
serialize=connection.settings_dict.get('TEST', {}).get('SERIALIZE', True),
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/creation.py", line 68, in create_test_db
run_syncdb=True,
File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 141, in call_command
return command.execute(*args, **defaults)
File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 335, in execute
output = self.handle(*args, **options)
File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 200, in handle
fake_initial=fake_initial,
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 117, in migrate
state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 244, in apply_migration
state = migration.apply(state, schema_editor)
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/migration.py", line 122, in apply
operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/operations/fields.py", line 216, in database_forwards
schema_editor.alter_field(from_model, from_field, to_field)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 509, in alter_field
old_db_params, new_db_params, strict)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 613, in _alter_field
old_default = self.effective_default(old_field)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/schema.py", line 224, in effective_default
default = field.get_db_prep_save(default, self.connection)
File "/usr/local/lib/python3.6/site-packages/django/db/models/fields/related.py", line 936, in get_db_prep_save
return self.target_field.get_db_prep_save(value, connection=connection)
File "/usr/local/lib/python3.6/site-packages/django/db/models/fields/__init__.py", line 767, in get_db_prep_save
return self.get_db_prep_value(value, connection=connection, prepared=False)
File "/usr/local/lib/python3.6/site-packages/django/db/models/fields/__init__.py", line 940, in get_db_prep_value
value = connection.ops.validate_autopk_value(value)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/mysql/operations.py", line 163, in validate_autopk_value
raise ValueError('The database backend does not accept 0 as a '
ValueError: The database backend does not accept 0 as a value for AutoField.
How can I fix this error and run the tests?
OK it seems it was indeed migrations as @Willem Van Onsem suggested. I ended up deleting the migrations and that cleared the issue.
It might be worth pointing out the the mess was caused by switching from Django models to Django MTPP models and using 0 as a default value for the newly added MTPP fields to avoid another issue in that process.