Signing in with a gaming account or with an SSH key could both bring a
user into existence. That makes an account only as recoverable as the
thing that created it, and gives one person as many accounts as they
have gaming logins — neither of which is what an account is supposed to
be now that verifying an address is what creates one.
Both are unwired rather than deleted. The provider implementations stay
where they are, because connecting a gaming account is still something
this product does; it just does it from the API, against a user who
already exists, which is a connection hanging off an identity rather
than an identity of its own.
The worker test followed: it exercised the two flows that are gone, and
now covers the one that is left plus an assertion that the other two are
not routed, so they cannot come back quietly.
Wires the pin-code provider, which existed and was never reachable, and makes
it the only branch that can create an account. Steam now resolves an existing
connection instead of minting a user from a persona, and refuses when there is
no account behind it — which is an answer the interface renders rather than an
implicit signup.
Delivery is a small provider-neutral POST rather than a vendor SDK: configure
an endpoint, a key and a from address. With none of them set it logs the code
outside production so a local sign-in works, and throws in production, because
a screen that says "check your email" when nothing was sent leaves someone
waiting instead of telling anybody.
A person who has only ever signed in by email has no connected account, and
the token says so with an empty value — the same one a server-to-server caller
has always carried.
