Cannot have multiple test functions in the same class inheriting from MigratorTestCase #467
Description
The way MigratorTestCase is implemented it is only possible to setup test data in the prepare function which is called during setUp. Because of that there is no way to setup different data for different test functions.
In order to be able to support multiple test functions MigratorTestCase could be implemented this way:
@tag(MIGRATION_TEST_MARKER)
class MigratorTestCase(TransactionTestCase):
"""Used when using raw ``unitest`` library for test."""
database_name: ClassVar[Optional[str]] = None
old_state: ProjectState
new_state: ProjectState
#: Part of the end-user API. Used to tell what migrations we are using.
migrate_from: ClassVar[MigrationSpec]
migrate_to: ClassVar[MigrationSpec]
auto_migrate: bool = True # <-------------- Add an option to disable automatic migration
def setUp(self) -> None:
"""
Regular ``unittest`` styled setup case.
What it does?
- It starts with defining the initial migration state
- Then it allows to run custom method
to prepare some data before the migration will happen
- Then it applies the migration and saves all states
"""
super().setUp()
self._migrator = Migrator(self.database_name)
self.old_state = self._migrator.apply_initial_migration(
self.migrate_from,
)
self.prepare()
if self.auto_migrate: # <-------------- check if auto_migrate is activated
self.migrate() # <-------------- call the extracted the method
# v-------------- do the migration
def migrate(self) -> None:
assert not hasattr(self, "new_state"), "migrate must be called only once"
self.new_state = self._migrator.apply_tested_migration(self.migrate_to)it would allow to add multiple test scenarios like this:
class Test1234(MigratorTestCase):
migrate_from = ...
migrate_to = ...
auto_migrate = False
def prepare(self):
... # prepare common stuff here
def test_scenario_1(self):
... # instantiate stuff here using old state
self.migrate()
... # validate migration here using new state
def test_scenario_2(self):
... # instantiate stuff here using old state
self.migrate()
... # validate migration here using new state