Respect tombstones in locally known rooms for Space children

src/components/structures/SpaceHierarchy.tsx

@@ -15,17 +15,17 @@ limitations under the License.
 */
 
 import React, {
+    Dispatch,
+    KeyboardEvent,
+    KeyboardEventHandler,
     ReactNode,
+    SetStateAction,
     useCallback,
+    useContext,
     useEffect,
     useMemo,
     useRef,
     useState,
-    KeyboardEvent,
-    KeyboardEventHandler,
-    useContext,
-    SetStateAction,
-    Dispatch,
 } from "react";
 import { Room } from "matrix-js-sdk/src/models/room";
 import { RoomHierarchy } from "matrix-js-sdk/src/room-hierarchy";
@@ -33,7 +33,8 @@ import { EventType, RoomType } from "matrix-js-sdk/src/@types/event";
 import { IHierarchyRelation, IHierarchyRoom } from "matrix-js-sdk/src/@types/spaces";
 import { MatrixClient } from "matrix-js-sdk/src/matrix";
 import classNames from "classnames";
-import { sortBy } from "lodash";
+import { sortBy, uniqBy } from "lodash";
+import { GuestAccess, HistoryVisibility } from "matrix-js-sdk/src/@types/partials";
 
 import dis from "../../dispatcher/dispatcher";
 import defaultDispatcher from "../../dispatcher/dispatcher";
@@ -48,7 +49,7 @@ import { mediaFromMxc } from "../../customisations/Media";
 import InfoTooltip from "../views/elements/InfoTooltip";
 import TextWithTooltip from "../views/elements/TextWithTooltip";
 import { useStateToggle } from "../../hooks/useStateToggle";
-import { getChildOrder } from "../../stores/SpaceStore";
+import SpaceStore, { getChildOrder } from "../../stores/SpaceStore";
 import AccessibleTooltipButton from "../views/elements/AccessibleTooltipButton";
 import { linkifyElement } from "../../HtmlUtils";
 import { useDispatcher } from "../../hooks/useDispatcher";
@@ -333,6 +334,29 @@ interface IHierarchyLevelProps {
     onToggleClick?(parentId: string, childId: string): void;
 }
 
+const toLocalRoom = (cli: MatrixClient, room: IHierarchyRoom, upgradedRoomMap: Map<string, string>): IHierarchyRoom => {
+    const cliRoom = cli.getRoom(SpaceStore.instance.findMostUpgradedVersion(room.room_id, upgradedRoomMap));
+    if (cliRoom) {
+        return {
+            ...room,
+            room_id: cliRoom.roomId,
+            room_type: cliRoom.getType(),
+            name: cliRoom.name,
+            topic: cliRoom.currentState.getStateEvents(EventType.RoomTopic, "")?.getContent().topic,
+            avatar_url: cliRoom.getMxcAvatarUrl(),
+            canonical_alias: cliRoom.getCanonicalAlias(),
+            aliases: cliRoom.getAltAliases(),
+            world_readable: cliRoom.currentState.getStateEvents(EventType.RoomHistoryVisibility, "")?.getContent()
+                .history_visibility === HistoryVisibility.WorldReadable,
+            guest_can_join: cliRoom.currentState.getStateEvents(EventType.RoomGuestAccess, "")?.getContent()
+                .guest_access === GuestAccess.CanJoin,
+            num_joined_members: cliRoom.getJoinedMemberCount(),
+        };
+    }
+
+    return room;
+};
+
 export const HierarchyLevel = ({
     root,
     roomSet,
@@ -350,10 +374,11 @@ export const HierarchyLevel = ({
         return getChildOrder(ev.content.order, ev.origin_server_ts, ev.state_key);
     });
 
+    const upgradedRoomMap = new Map<string, string>();
     const [subspaces, childRooms] = sortedChildren.reduce((result, ev: IHierarchyRelation) => {
         const room = hierarchy.roomMap.get(ev.state_key);
         if (room && roomSet.has(room)) {
-            result[room.room_type === RoomType.Space ? 0 : 1].push(room);
+            result[room.room_type === RoomType.Space ? 0 : 1].push(toLocalRoom(cli, room, upgradedRoomMap));
         }
         return result;
     }, [[] as IHierarchyRoom[], [] as IHierarchyRoom[]]);
@@ -361,7 +386,7 @@ export const HierarchyLevel = ({
     const newParents = new Set(parents).add(root.room_id);
     return <React.Fragment>
         {
-            childRooms.map(room => (
+            uniqBy(childRooms, "room_id").map(room => (
                 <Tile
                     key={room.room_id}
                     room={room}

src/stores/SpaceStore.ts

@@ -283,7 +283,7 @@ export class SpaceStoreClass extends AsyncStoreWithClient<IState> {
             const createTs = childRoom?.currentState.getStateEvents(EventType.RoomCreate, "")?.getTs();
             return getChildOrder(ev.getContent().order, createTs, roomId);
         }).map(ev => {
-            return this.matrixClient.getRoom(ev.getStateKey());
+            return this.matrixClient.getRoom(this.findMostUpgradedVersion(ev.getStateKey()));
         }).filter(room => {
             return room?.getMyMembership() === "join" || room?.getMyMembership() === "invite";
         }) || [];
@@ -452,6 +452,28 @@ export class SpaceStoreClass extends AsyncStoreWithClient<IState> {
         this.onRoomsUpdate();
     };
 
+    // Utility to walk tombstones and find the most updated variant of the given room,
+    // takes a Map to enable caching of the responses given the recursive nature of the function.
+    public findMostUpgradedVersion(
+        roomId: string,
+        upgradedRoomMap?: Map<string, string>,
+        seen= new Set<string>(),
+    ): string {
+        if (seen.has(roomId)) return roomId;
+        if (upgradedRoomMap?.has(roomId)) return upgradedRoomMap.get(roomId);
+        const room = this.matrixClient.getRoom(roomId);
+        const tombstone = room?.currentState.getStateEvents(EventType.RoomTombstone, "");
+        const replacementRoom = tombstone?.getContent().replacement_room;
+        if (replacementRoom && this.matrixClient.getRoom(replacementRoom)?.getMyMembership() === "join") {
+            seen.add(roomId);
+            const result = this.findMostUpgradedVersion(replacementRoom, upgradedRoomMap);
+            upgradedRoomMap?.set(roomId, result);
+            return result;
+        }
+        upgradedRoomMap?.set(roomId, roomId);
+        return roomId;
+    }
+
     private onRoomsUpdate = throttle(() => {
         // TODO resolve some updates as deltas
         const visibleRooms = this.matrixClient.getVisibleRooms();
@@ -479,6 +501,7 @@ export class SpaceStoreClass extends AsyncStoreWithClient<IState> {
             });
         });
 
+        const upgradedRoomMap = new Map<string, string>();
         this.rootSpaces.forEach(s => {
             // traverse each space tree in DFS to build up the supersets as you go up,
             // reusing results from like subtrees.
@@ -491,7 +514,7 @@ export class SpaceStoreClass extends AsyncStoreWithClient<IState> {
                 }
 
                 const [childSpaces, childRooms] = partitionSpacesAndRooms(this.getChildren(spaceId));
-                const roomIds = new Set(childRooms.map(r => r.roomId));
+                const roomIds = new Set(childRooms.map(r => this.findMostUpgradedVersion(r.roomId, upgradedRoomMap)));
                 const space = this.matrixClient?.getRoom(spaceId);
 
                 // Add relevant DMs
@@ -505,11 +528,11 @@ export class SpaceStoreClass extends AsyncStoreWithClient<IState> {
                 const newPath = new Set(parentPath).add(spaceId);
                 childSpaces.forEach(childSpace => {
                     fn(childSpace.roomId, newPath)?.forEach(roomId => {
-                        roomIds.add(roomId);
+                        roomIds.add(this.findMostUpgradedVersion(roomId, upgradedRoomMap));
                     });
                 });
                 hiddenChildren.get(spaceId)?.forEach(roomId => {
-                    roomIds.add(roomId);
+                    roomIds.add(this.findMostUpgradedVersion(roomId, upgradedRoomMap));
                 });
                 this.spaceFilteredRooms.set(spaceId, roomIds);
                 return roomIds;