allow passing txn to loadMembers so we can do it as part of sync txn

to rewrite useridentities upon receiving new history visibility

src/matrix/e2ee/DeviceTracker.js

@@ -116,12 +116,13 @@ export class DeviceTracker {
         if (room.isTrackingMembers || !room.isEncrypted) {
             return;
         }
-        const memberList = await room.loadMemberList(log);
+        const txn = await this._storage.readWriteTxn([
+            this._storage.storeNames.roomSummary,
+            this._storage.storeNames.userIdentities,
+        ]);
+        let memberList;
         try {
-            const txn = await this._storage.readWriteTxn([
-                this._storage.storeNames.roomSummary,
-                this._storage.storeNames.userIdentities,
-            ]);
+            memberList = await room.loadMemberList(txn, log);
             let isTrackingChanges;
             try {
                 isTrackingChanges = room.writeIsTrackingMembers(true, txn);
@@ -139,7 +140,7 @@ export class DeviceTracker {
             await txn.complete();
             room.applyIsTrackingMembersChanges(isTrackingChanges);
         } finally {
-            memberList.release();
+            memberList?.release();
         }
     }
 

src/matrix/room/BaseRoom.js

@@ -243,7 +243,7 @@ export class BaseRoom extends EventEmitter {
 
 
     /** @public */
-    async loadMemberList(log = null) {
+    async loadMemberList(txn = undefined, log = null) {
         if (this._memberList) {
             // TODO: also await fetchOrLoadMembers promise here
             this._memberList.retain();
@@ -254,6 +254,9 @@ export class BaseRoom extends EventEmitter {
                 roomId: this._roomId,
                 hsApi: this._hsApi,
                 storage: this._storage,
+                // pass in a transaction if we know we won't need to fetch (which would abort the transaction)
+                // and we want to make this operation part of the larger transaction
+                txn,
                 syncToken: this._getSyncToken(),
                 // to handle race between /members and /sync
                 setChangedMembersMap: map => this._changedMembersDuringSync = map,

src/matrix/room/members/load.js

@@ -17,10 +17,12 @@ limitations under the License.
 
 import {RoomMember} from "./RoomMember.js";
 
-async function loadMembers({roomId, storage}) {
-    const txn = await storage.readTxn([
-        storage.storeNames.roomMembers,
-    ]);
+async function loadMembers({roomId, storage, txn}) {
+    if (!txn) {
+        txn = await storage.readTxn([
+            storage.storeNames.roomMembers,
+        ]);
+    }
     const memberDatas = await txn.roomMembers.getAll(roomId);
     return memberDatas.map(d => new RoomMember(d));
 }