Merge pull request #1801 from matrix-org/gsouquet/localecompare-perf

Improve calculateRoomName performances by using Intl.Collator

src/models/room.ts

@@ -2053,7 +2053,7 @@ export class Room extends EventEmitter {
                     (m.membership === "invite" || m.membership === "join");
             });
             // make sure members have stable order
-            otherMembers.sort((a, b) => a.userId.localeCompare(b.userId));
+            otherMembers.sort((a, b) => utils.compare(a.userId, b.userId));
             // only 5 first members, immitate summaryHeroes
             otherMembers = otherMembers.slice(0, 5);
             otherNames = otherMembers.map((m) => m.name);

src/utils.ts

@@ -683,3 +683,13 @@ export function lexicographicCompare(a: string, b: string): number {
     // hidden the operation in this function.
     return (a < b) ? -1 : ((a === b) ? 0 : 1);
 }
+
+const collator = new Intl.Collator();
+/**
+ * Performant language-sensitive string comparison
+ * @param a the first string to compare
+ * @param b the second string to compare
+ */
+export function compare(a: string, b: string): number {
+    return collator.compare(a, b);
+}