For every Project instance, create an Org instance

[iaindillingham]

#4505 ensures that if a template is missing a variable, and if that template's SimpleTemplateResponse is rendered in a test (.render() or .rendered_content), then the test will fail 💥

There are, undoubtedly, cases where a template is really missing a variable (true positives). However, there are also cases where a template is missing a variable simply because the test context doesn't reflect the production context (false positives). Many of these cases involve the relationship between Project and Org through Project.org:

job-server/jobserver/models/project.py

Lines 201 to 203 in 8656ca1

	@functional.cached_property
	def org(self):
	return self.orgs.filter(collaborations__is_lead=True).first()

Yes, that's correct: the relationship isn't a ForeignKey on Project. Consequently, factory_boy, which we use to create the test context, doesn't instantiate an Org when it instantiates a Project. Brace yourself:

job-server/tests/factories/project.py

Line 33 in 8656ca1

org = factory.PostGeneration(_project_collaboration_factory)

job-server/tests/factories/project.py

Lines 8 to 19 in 8656ca1

	def _project_collaboration_factory(obj, create, extracted, **kwargs):
	from . import ProjectCollaborationFactory
	if not create or not extracted:
	# Simple build, or nothing to add, do nothing.
	return
	extracted = extracted if isinstance(extracted, abc.Iterable) else [extracted]
	# Add the iterable of groups using bulk addition
	for org in extracted:
	ProjectCollaborationFactory(org=org, project=obj, is_lead=True)

This means that to cajole factory_boy into instantiating an Org and a Project, we have to do something like ProjectFactory(org=OrgFactory()) or ProjectFactory(orgs=[OrgFactory()]). And this is both easy to forget and, when the tests fail, hard to interpret.

It would be much cleaner 🪥 if every time a Project was instantiated, then an Org was instantiated too.