GMime.RfcComplianceMode.LOOSE does not allow square bracets in email address

[bellegarde-c]

See [geary#1385](https://gitlab.gnome.org/GNOME/geary/-/issues/1385)

Geary is using GMime.InternetAddressList.parse() to validate email addresses but it returns NULL when having square bracets.

[jstedfast]

The name is not allowed to contain raw []'s. From rfc5322:

   address         =   mailbox / group

   mailbox         =   name-addr / addr-spec

   name-addr       =   [display-name] angle-addr

   angle-addr      =   [CFWS] "<" addr-spec ">" [CFWS] /
                       obs-angle-addr

   group           =   display-name ":" [group-list] ";" [CFWS]

   display-name    =   phrase

   word            =   atom / quoted-string

   phrase          =   1*word / obs-phrase

   atext           =   ALPHA / DIGIT /    ; Printable US-ASCII
                       "!" / "#" /        ;  characters not including
                       "$" / "%" /        ;  specials.  Used for atoms.
                       "&" / "'" /
                       "*" / "+" /
                       "-" / "/" /
                       "=" / "?" /
                       "^" / "_" /
                       "`" / "{" /
                       "|" / "}" /
                       "~"

   atom            =   [CFWS] 1*atext [CFWS]

   specials        =   "(" / ")" /        ; Special characters that do
                       "<" / ">" /        ;  not appear in atext
                       "[" / "]" /
                       ":" / ";" /
                       "@" / "\" /
                       "," / "." /
                       DQUOTE

As you can see here, a display-name needs to match the phrase syntax, which is 1-or-more word tokens where each word token is either a quoted-string or an atom. An atom must only consist of Alpha-Numeric characters or one of the allowed punctuation characters from the atext definition which does not include [ or ].

[bellegarde-c]

Yes I know but Thunderbird and Outlook allow them... :(

[jstedfast]

Is this something that the user is typing into the To text box in the message composer? Or what is the scenario?

[bellegarde-c]

Mail received from a Thunderbird/Outlook client from "user[compagny] user@compagny.com", you reply and geary just fails to validate sender.

[jstedfast]

Okay, but that sounds like Geary isn't properly quoting the name when it stuffs it into the text field though, right?

Because obviously gmime properly parsed it from the From header in order for the []'s to end up in the To textbox when hitting reply.

[bellegarde-c]

You reply and Geary just fails to validate the sender means "send button disabled" because of textbox content.

[jstedfast]

What I'm suggesting is that Geary needs to format the email address such that the []'s are inside a quoted-string when it adds the email address to an address field in your composer window.

If Geary is using internet_address_to_string() or internet_address_list_to_string(), there might be a bug there, but it's not a bug in the parser.

[bellegarde-c]

Ok, wil give a look! Thanks!

[jstedfast]

Did that solve the problem?

[bellegarde-c]

Sorry, did not find time to but will.