pub fn resolve_from(
send_as: &[SendAs],
from: &Mailbox,
) -> Result<Option<Mailbox>>Expand description
Checks from against the account’s send-as addresses and returns the
mailbox to write as the draft’s From, or None to leave From to
Gmail.
The address matches sendAsEmail case-insensitively and is written in
the stored spelling. An alias still awaiting verification is refused,
as is an address that isn’t one of send_as: Gmail would send from the
primary address instead, or not at all.
Without a name in from, the name is the alias’s non-blank
displayName, else the primary address’s, which is the name Gmail
itself sends a nameless alias under. When that leaves the primary address
with no name, the result is None: Gmail fills in the primary address
and the Google account’s name, which a nameless From would lose.