Implement XEP-0463: MUC Affiliations Versioning

parsers/src/muc/mav.rs

@@ -0,0 +1,69 @@
+// Copyright (c) 2026 Link Mauve <linkmauve@linkmauve.fr>
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+use xso::{AsXml, FromXml};
+
+use crate::ns;
+
+generate_id!(
+    /// Unique and opaque string, indicating the last affiliation version sent by the server that
+    /// the client has seen, and cached.
+    Version
+);
+
+/// A `<mav/>` element sent by the client on join, if it wants to keep track of the affiliations in
+/// the room.
+#[derive(FromXml, AsXml, Debug, Clone, PartialEq)]
+#[xml(namespace = ns::MAV, name = "mav")]
+pub struct AffiliationsVersioning {
+    /// Unique and opaque string, indicating the last affiliation version sent by the server that
+    /// the client has seen, and cached.  Sending the mav element without a since attribute is a
+    /// called bootstrap request, which asks the server for a full response.
+    #[xml(attribute(default))]
+    since: Option<Version>,
+
+    /// The latest version the server has.
+    #[xml(attribute(default))]
+    until: Option<Version>,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use minidom::Element;
+
+    #[cfg(target_pointer_width = "32")]
+    #[test]
+    fn test_size() {
+        assert_size!(Version, 12);
+        assert_size!(AffiliationsVersioning, 24);
+    }
+
+    #[cfg(target_pointer_width = "64")]
+    #[test]
+    fn test_size() {
+        assert_size!(Version, 24);
+        assert_size!(AffiliationsVersioning, 48);
+    }
+
+    #[test]
+    fn test_simple() {
+        let elem: Element = "<mav xmlns='urn:xmpp:muc:affiliations:1'/>"
+            .parse()
+            .unwrap();
+        let ver = AffiliationsVersioning::try_from(elem).unwrap();
+        assert!(ver.since.is_none());
+        assert!(ver.until.is_none());
+
+        let elem: Element =
+            "<mav xmlns='urn:xmpp:muc:affiliations:1' since='9pacabr2q1' until='ruz41312vw'/>"
+                .parse()
+                .unwrap();
+        let ver = AffiliationsVersioning::try_from(elem).unwrap();
+        assert_eq!(ver.since.unwrap().0, "9pacabr2q1");
+        assert_eq!(ver.until.unwrap().0, "ruz41312vw");
+    }
+}

parsers/src/muc/mod.rs

@@ -11,5 +11,8 @@ pub mod muc;
 /// The `http://jabber.org/protocol/muc#user` protocol.
 pub mod user;
 
+/// The `urn:xmpp:muc:affiliations:1` protocol.
+pub mod mav;
+
 pub use self::muc::Muc;
 pub use self::user::MucUser;

parsers/src/muc/user.rs

@@ -8,6 +8,7 @@
 use xso::{AsXml, FromXml};
 
 use crate::message::MessagePayload;
+use crate::muc::mav::AffiliationsVersioning;
 use crate::ns;
 use crate::presence::PresencePayload;
 
@@ -302,6 +303,10 @@ pub struct MucUser {
     /// A mediated invite rejection
     #[xml(child(default))]
     pub decline: Option<Decline>,
+
+    /// From XEP-0463: MUC Affiliations Versioning
+    #[xml(child(default))]
+    pub affiliations: Option<AffiliationsVersioning>,
 }
 
 impl MucUser {
@@ -347,7 +352,7 @@ mod tests {
         assert_size!(Item, 84);
         assert_size!(Invite, 44);
         assert_size!(Decline, 44);
-        assert_size!(MucUser, 112);
+        assert_size!(MucUser, 136);
     }
 
     #[cfg(target_pointer_width = "64")]
@@ -362,7 +367,7 @@ mod tests {
         assert_size!(Item, 168);
         assert_size!(Invite, 88);
         assert_size!(Decline, 88);
-        assert_size!(MucUser, 224);
+        assert_size!(MucUser, 272);
     }
 
     #[test]