prop140: What to do when a diff fails to apply?

Right now, we treat failures to apply a consensus diff as if the consensus download had failed. Is this what we should be doing?

(Formerly part of #22148 (moved))

changed milestone to %Tor: 0.3.1.x-final

added component::core tor/tor milestone::Tor: 0.3.1.x-final owner::nickm priority::medium resolution::worksforme severity::normal sponsor::4 status::closed type::defect labels

Trac:
Status: new to accepted
Owner: N/A to nickm

I think we can treat a non-applying diff as if we had downloaded a bogus consensus. Rationale: we provided the source SHA3 digest that the diff is supposed to apply to; if it doesn't apply, then the cache is deeply confused, or we are.

Putting this into needs_information. I want to keep an eye on this as we try it in practice, but I think that the current approach will likely turn out to be okay.

Trac:
Status: accepted to needs_information

Trac:
Parent: #13339 (moved) to N/A

Trac:
Resolution: N/A to worksforme
Status: needs_information to closed

closed

moved to tpo/core/tor#22172 (closed)