events: Allow to add mentions automatically when generating reply

crates/ruma-common/CHANGELOG.md

@@ -37,7 +37,9 @@ Breaking changes:
   MSC2176 / MSC3821 / MSC3820, for the following types:
   - `RedactedRoomRedactionEventContent`,
   - `RedactedRoomPowerLevelsEventContent`,
-  - `RedactedRoomMemberEventContent` 
+  - `RedactedRoomMemberEventContent`
+- `RoomMessageEventContent::make_reply_to()` and `make_for_thread()` have an extra parameter to
+  support the recommended behavior for intentional mentions in replies according to Matrix 1.7
 
 Improvements:
 

crates/ruma-common/src/events/room/message.rs

@@ -150,6 +150,7 @@ impl RoomMessageEventContent {
         mut self,
         original_message: &OriginalRoomMessageEvent,
         forward_thread: ForwardThread,
+        add_mentions: AddMentions,
     ) -> Self {
         let empty_formatted_body = || FormattedBody::html(String::new());
 
@@ -205,6 +206,17 @@ impl RoomMessageEventContent {
         };
         self.relates_to = Some(relates_to);
 
+        if add_mentions == AddMentions::Yes {
+            // Copy the mentioned users.
+            let mut user_ids = match &original_message.content.mentions {
+                Some(m) => m.user_ids.clone(),
+                None => Default::default(),
+            };
+            // Add the sender.
+            user_ids.insert(original_message.sender.clone());
+            self.mentions = Some(Mentions { user_ids, ..Default::default() });
+        }
+
         self
     }
 
@@ -227,9 +239,10 @@ impl RoomMessageEventContent {
         mut self,
         previous_message: &OriginalRoomMessageEvent,
         is_reply: ReplyWithinThread,
+        add_mentions: AddMentions,
     ) -> Self {
         if is_reply == ReplyWithinThread::Yes {
-            self = self.make_reply_to(previous_message, ForwardThread::No);
+            self = self.make_reply_to(previous_message, ForwardThread::No, add_mentions);
         }
 
         let thread_root = if let Some(Relation::Thread(Thread { event_id, .. })) =
@@ -323,7 +336,7 @@ impl RoomMessageEventContent {
 
         // Add reply fallback if needed.
         if let Some(original_message) = replied_to_message {
-            self = self.make_reply_to(original_message, ForwardThread::No);
+            self = self.make_reply_to(original_message, ForwardThread::No, AddMentions::No);
         }
 
         self.relates_to = Some(relates_to);
@@ -473,6 +486,24 @@ pub enum ForwardThread {
     No,
 }
 
+/// Whether or not to add intentional [`Mentions`] when sending a reply.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[allow(clippy::exhaustive_enums)]
+pub enum AddMentions {
+    /// Add automatic intentional mentions to the reply.
+    ///
+    /// Set this if your client supports intentional mentions.
+    ///
+    /// The sender of the original event will be added to the mentions of this message, along with
+    /// every user mentioned in the original event.
+    Yes,
+
+    /// Do not add intentional mentions to the reply.
+    ///
+    /// Set this if your client does not support intentional mentions.
+    No,
+}
+
 /// Whether or not the message is a reply inside a thread.
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 #[allow(clippy::exhaustive_enums)]

crates/ruma-common/tests/events/room_message.rs

@@ -7,10 +7,11 @@ use ruma_common::{
         key::verification::VerificationMethod,
         room::{
             message::{
-                AudioMessageEventContent, EmoteMessageEventContent, FileMessageEventContent,
-                ForwardThread, ImageMessageEventContent, KeyVerificationRequestEventContent,
-                MessageType, OriginalRoomMessageEvent, OriginalSyncRoomMessageEvent, Relation,
-                RoomMessageEventContent, TextMessageEventContent, VideoMessageEventContent,
+                AddMentions, AudioMessageEventContent, EmoteMessageEventContent,
+                FileMessageEventContent, ForwardThread, ImageMessageEventContent,
+                KeyVerificationRequestEventContent, MessageType, OriginalRoomMessageEvent,
+                OriginalSyncRoomMessageEvent, Relation, RoomMessageEventContent,
+                TextMessageEventContent, VideoMessageEventContent,
             },
             EncryptedFileInit, JsonWebKeyInit, MediaSource,
         },
@@ -265,8 +266,11 @@ fn escape_tags_in_plain_reply_body() {
         sender: owned_user_id!("@user:example.org"),
         unsigned: MessageLikeUnsigned::default(),
     };
-    let second_message = RoomMessageEventContent::text_plain("Usage: rm <path>")
-        .make_reply_to(&first_message, ForwardThread::Yes);
+    let second_message = RoomMessageEventContent::text_plain("Usage: rm <path>").make_reply_to(
+        &first_message,
+        ForwardThread::Yes,
+        AddMentions::No,
+    );
 
     assert_matches!(
         first_message.content.msgtype,
@@ -324,7 +328,7 @@ fn reply_sanitize() {
             "This is the _second_ message",
             "This is the <em>second</em> message",
         )
-        .make_reply_to(&first_message, ForwardThread::Yes),
+        .make_reply_to(&first_message, ForwardThread::Yes, AddMentions::No),
         event_id: owned_event_id!("$143273582443PhrSn:example.org"),
         origin_server_ts: MilliSecondsSinceUnixEpoch(uint!(10_000)),
         room_id: owned_room_id!("!testroomid:example.org"),
@@ -335,7 +339,7 @@ fn reply_sanitize() {
         "This is **my** reply",
         "This is <strong>my</strong> reply",
     )
-    .make_reply_to(&second_message, ForwardThread::Yes);
+    .make_reply_to(&second_message, ForwardThread::Yes, AddMentions::No);
 
     assert_matches!(
         first_message.content.msgtype,
@@ -844,7 +848,7 @@ fn set_mentions() {
     let user_id = owned_user_id!("@you:localhost");
     content = content.set_mentions(Mentions::with_user_ids(vec![user_id.clone()]));
     let mentions = content.mentions.unwrap();
-    assert_eq!(mentions.user_ids.as_slice(), &[user_id]);
+    assert_eq!(mentions.user_ids, [user_id].into());
 }
 
 #[test]
@@ -878,14 +882,14 @@ fn make_replacement_set_mentions() {
     assert_matches!(content.mentions, None);
     assert_matches!(content.relates_to, Some(Relation::Replacement(replacement)));
     let mentions = replacement.new_content.mentions.unwrap();
-    assert_eq!(mentions.user_ids.as_slice(), &[alice.clone()]);
+    assert_eq!(mentions.user_ids, [alice.clone()].into());
 
     content = content_clone.set_mentions(Mentions::with_user_ids(vec![alice.clone(), bob.clone()]));
     let mentions = content.mentions.unwrap();
-    assert_eq!(mentions.user_ids.as_slice(), &[bob.clone()]);
+    assert_eq!(mentions.user_ids, [bob.clone()].into());
     assert_matches!(content.relates_to, Some(Relation::Replacement(replacement)));
     let mentions = replacement.new_content.mentions.unwrap();
-    assert_eq!(mentions.user_ids.as_slice(), &[alice, bob]);
+    assert_eq!(mentions.user_ids, [alice, bob].into());
 }
 
 #[test]