How to fix an error when running tests?

Question

Django

Greetings, how to fix the error to delete the test database?

Creating test database for alias 'default'...
Got an error creating the test database: (1007, "Can't create database 'test_develop'; database exists")
Type 'yes' if you would like to try deleting the test database 'test_develop', or 'no' to cancel: yes
Destroying old test database for alias 'default'...
Traceback (most recent call last):
  File "manage.py", line 11, in <module>
    execute_from_command_line(sys.argv)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/__init__.py", line 353, in execute_from_command_line
    utility.execute()
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/__init__.py", line 345, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/commands/test.py", line 30, in run_from_argv
    super(Command, self).run_from_argv(argv)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/base.py", line 348, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/commands/test.py", line 74, in execute
    super(Command, self).execute(*args, **options)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/base.py", line 399, in execute
    output = self.handle(*args, **options)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/commands/test.py", line 90, in handle
    failures = test_runner.run_tests(test_labels)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/test/runner.py", line 532, in run_tests
    old_config = self.setup_databases()
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/test/runner.py", line 482, in setup_databases
    self.parallel, **kwargs
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/test/runner.py", line 726, in setup_databases
    serialize=connection.settings_dict.get("TEST", {}).get("SERIALIZE", True),
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/backends/base/creation.py", line 70, in create_test_db
    run_syncdb=True,
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/__init__.py", line 119, in call_command
    return command.execute(*args, **defaults)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/base.py", line 399, in execute
    output = self.handle(*args, **options)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/core/management/commands/migrate.py", line 200, in handle
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/migrations/executor.py", line 92, in migrate
    self._migrate_all_forwards(plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/migrations/executor.py", line 121, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/migrations/executor.py", line 198, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/migrations/migration.py", line 123, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/migrations/operations/fields.py", line 62, in database_forwards
    field,
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/backends/mysql/schema.py", line 50, in add_field
    super(DatabaseSchemaEditor, self).add_field(model, field)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 382, in add_field
    definition, params = self.column_sql(model, field, include_default=True)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 145, in column_sql
    default_value = self.effective_default(field)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 210, in effective_default
    default = field.get_db_prep_save(default, self.connection)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/models/fields/__init__.py", line 728, in get_db_prep_save
    prepared=False)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/models/fields/__init__.py", line 1461, in get_db_prep_value
    value = self.get_prep_value(value)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/models/fields/__init__.py", line 1440, in get_prep_value
    value = super(DateTimeField, self).get_prep_value(value)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/models/fields/__init__.py", line 1296, in get_prep_value
    return self.to_python(value)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/db/models/fields/__init__.py", line 1399, in to_python
    parsed = parse_datetime(value)
  File "/home/maxim/PycharmProjects/venv/alpha/lib/python3.5/site-packages/django/utils/dateparse.py", line 93, in parse_datetime
    match = datetime_re.match(value)
TypeError: expected string or bytes-like object

Answer 1

It seems to me that the problem does not arise when the database is deleted, but when a new one is created, when migrations are applied to one of the fields DateTimeField.

• If the project is educational and it is not a pity to delete the migrations, then delete and make new ones, check if the problem will be repeated.
  
• If it's a pity - do grep DateTimeField */migrations/*it for all migrations and see if there are any incorrect datetime values ​​\u200b\u200b(for example, as an argument default).
  
• And also check the same fields in all models.pyfor the same.