Some invalid proofs would be nice

I’ve been implementing the proofs for OpenKeychain, and I’ve had to put in a bunch of tedious work hard-wiring mocks of this kind and that with failing proofs, just to test (a) that I catch them and (b) that I report them sanely.

It’d be nice for 3rd-party implementors like me if there were bogus Keybase account or two all of whose proofs were invalid in one way or another.

Start by locating the existing proof-validation tests and test-account fixtures used by OpenKeychain. Check how invalid Keybase proofs are represented and whether a reusable bogus account can be added. Done means third-party implementors can exercise invalid-proof handling without hard-wiring mocks, with sane error reporting covered by tests.

Written by the indexing model from the issue text.