From 6155772bb1f85fbaf71cfd38ba16f5c8e166ca1d Mon Sep 17 00:00:00 2001
From: Ivan Enderlin <ivan@mnt.io>
Date: Wed, 27 Aug 2025 15:51:24 +0200
Subject: [PATCH] feat(base): Add `RoomInfo::new_latest_event`.

This patch adds the new `new_latest_event: LatestEventValue` field in
`RoomInfo`. The `latest_event` is kept for the moment, but it will be
removed once the new API has landed entirely.
---
 crates/matrix-sdk-base/src/room/room_info.rs    | 17 +++++++++++++++--
 .../src/store/migration_helpers.rs              |  3 ++-
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/crates/matrix-sdk-base/src/room/room_info.rs b/crates/matrix-sdk-base/src/room/room_info.rs
index 46961fbc3..3a24e46dc 100644
--- a/crates/matrix-sdk-base/src/room/room_info.rs
+++ b/crates/matrix-sdk-base/src/room/room_info.rs
@@ -62,7 +62,7 @@ use super::{
 use crate::{
     MinimalStateEvent, OriginalMinimalStateEvent,
     deserialized_responses::RawSyncOrStrippedState,
-    latest_event::LatestEvent,
+    latest_event::{LatestEvent, LatestEventValue},
     notification_settings::RoomNotificationMode,
     read_receipts::RoomReadReceipts,
     store::{DynStateStore, StateStoreExt},
@@ -453,8 +453,16 @@ pub struct RoomInfo {
     pub(crate) encryption_state_synced: bool,
 
     /// The last event send by sliding sync
+    ///
+    /// TODO(@hywan): Remove.
     pub(crate) latest_event: Option<Box<LatestEvent>>,
 
+    /// The latest event value of this room.
+    ///
+    /// TODO(@hywan): Rename to `latest_event`.
+    #[serde(default)]
+    pub(crate) new_latest_event: LatestEventValue,
+
     /// Information about read receipts for this room.
     #[serde(default)]
     pub(crate) read_receipts: RoomReadReceipts,
@@ -512,6 +520,7 @@ impl RoomInfo {
             sync_info: SyncInfo::NoState,
             encryption_state_synced: false,
             latest_event: None,
+            new_latest_event: LatestEventValue::default(),
             read_receipts: Default::default(),
             base_info: Box::new(BaseRoomInfo::new()),
             warned_about_unknown_room_version_rules: Arc::new(false.into()),
@@ -1239,6 +1248,7 @@ impl Default for RoomInfoNotableUpdateReasons {
 mod tests {
     use std::sync::Arc;
 
+    use assert_matches::assert_matches;
     use matrix_sdk_common::deserialized_responses::TimelineEvent;
     use matrix_sdk_test::{
         async_test,
@@ -1251,7 +1261,7 @@ mod tests {
     use serde_json::json;
     use similar_asserts::assert_eq;
 
-    use super::{BaseRoomInfo, RoomInfo, SyncInfo};
+    use super::{BaseRoomInfo, LatestEventValue, RoomInfo, SyncInfo};
     use crate::{
         RoomDisplayName, RoomHero, RoomState, StateChanges,
         latest_event::LatestEvent,
@@ -1290,6 +1300,7 @@ mod tests {
             latest_event: Some(Box::new(LatestEvent::new(TimelineEvent::from_plaintext(
                 Raw::from_json_string(json!({"sender": "@u:i.uk"}).to_string()).unwrap(),
             )))),
+            new_latest_event: LatestEventValue::None,
             base_info: Box::new(
                 assign!(BaseRoomInfo::new(), { pinned_events: Some(RoomPinnedEventsEventContent::new(vec![owned_event_id!("$a")])) }),
             ),
@@ -1328,6 +1339,7 @@ mod tests {
                     "thread_summary": "None"
                 },
             },
+            "new_latest_event": "None",
             "base_info": {
                 "avatar": null,
                 "canonical_alias": null,
@@ -1523,6 +1535,7 @@ mod tests {
         assert_eq!(info.sync_info, SyncInfo::FullySynced);
         assert!(info.encryption_state_synced);
         assert!(info.latest_event.is_none());
+        assert_matches!(info.new_latest_event, LatestEventValue::None);
         assert!(info.base_info.avatar.is_none());
         assert!(info.base_info.canonical_alias.is_none());
         assert!(info.base_info.create.is_none());
diff --git a/crates/matrix-sdk-base/src/store/migration_helpers.rs b/crates/matrix-sdk-base/src/store/migration_helpers.rs
index df188cced..681a360a8 100644
--- a/crates/matrix-sdk-base/src/store/migration_helpers.rs
+++ b/crates/matrix-sdk-base/src/store/migration_helpers.rs
@@ -45,7 +45,7 @@ use serde::{Deserialize, Serialize};
 use crate::{
     MinimalStateEvent, OriginalMinimalStateEvent, RoomInfo, RoomState,
     deserialized_responses::SyncOrStrippedState,
-    latest_event::LatestEvent,
+    latest_event::{LatestEvent, LatestEventValue},
     room::{BaseRoomInfo, RoomSummary, SyncInfo},
     sync::UnreadNotificationsCount,
 };
@@ -116,6 +116,7 @@ impl RoomInfoV1 {
             sync_info,
             encryption_state_synced,
             latest_event: latest_event.map(|ev| Box::new(LatestEvent::new(ev))),
+            new_latest_event: LatestEventValue::None,
             read_receipts: Default::default(),
             base_info: base_info.migrate(create),
             warned_about_unknown_room_version_rules: Arc::new(false.into()),