search for the sentbox in two passes:
- first check the folder attributes
- only if that fails, check for some known names
this way, the sent-attribute always has precedence
over the name; this was not the case before.
moreover, this fixes an possibly wrong early exist
when the attribute list is completely empty.
* First try making get_recipients use MailHeader (nice and functional)
* Get it to compile by using not-so-functional style
* Add "empty-from" test, drop unnecessary check for error; continue using addrparse_header() instead of addrparse()
* Try to use functional style, unfortunately, I can't get the compiler to accept it
* Do it imperative-style: Do not overwrite To with Cc and vice versa
* Use addrparse_header() once more
* Still addrparse_header()
* Clippy
* Fix compile errors in tests
* Fix typo
* Fix tests again ;-)
* Code style
* Code style; try a HashMap<addr: String, display_name: String> as an address list but I am not convinced
* Code style; Use Vec<SingleInfo> as address list
* Clippy
* Add tests
* Add another test
* Remove stale comments
If error is ignored, the message will never be fetched again, even if
there was a database write error.
dc_receive_imf itself is modified to ignore unrecoverable errors, to
prevent endless refetching of incorrect messages.
If precheck_imf fails to check if message with the same rfc724_mid
already exists, the same message may be downloaded twice. Instead,
abort the whole operation and retry later.
Now 0 means "never delete", 1 means "delete at once" and other values
indicate the number of seconds after which them message should be
deleted from the server.
Configuration value interpretation is moved into
Context.get_config_delete_server_after() function.
Mutable UID reference is removed. Instead, ImapActionResult is
returned immediately.
If message has changed and UID does not correspond to expected
message, ImapActionResult::Failed is returned. Temprorary IMAP errors
result in ImapActionResult::RetryLater.
On the job side, ImapActionResult::RetryLater does not result in
immediate job retry anymore. Instead, job is retried with a backoff.
Envelope has the same Message-ID, but using other fields from the
envelope, such as From field, is error-prone. They may contain values
different from the message body. As we don't parse the envelope later on,
it is better not to fetch it during prefetch too.
