Restore createRoom.canEncryptToAllUsers behaviour

src/createRoom.ts

@@ -399,11 +399,9 @@ export async function canEncryptToAllUsers(client: MatrixClient, userIds: string
     try {
         const usersDeviceMap = await client.downloadKeys(userIds);
 
-        // There are no devices at all.
-        if (usersDeviceMap.size === 0) return false;
-
         for (const devices of usersDeviceMap.values()) {
             if (devices.size === 0) {
+                // This user does not have any encryption-capable devices.
                 return false;
             }
         }

test/createRoom-test.ts

@@ -161,10 +161,16 @@ describe("canEncryptToAllUsers", () => {
         client = mocked(stubClient());
     });
 
-    it("should return false if download keys does not return any user", async () => {
+    it("should return true if userIds is empty", async () => {
+        client.downloadKeys.mockResolvedValue(new Map());
+        const result = await canEncryptToAllUsers(client, []);
+        expect(result).toBe(true);
+    });
+
+    it("should return true if download keys does not return any user", async () => {
         client.downloadKeys.mockResolvedValue(new Map());
         const result = await canEncryptToAllUsers(client, [user1Id, user2Id]);
-        expect(result).toBe(false);
+        expect(result).toBe(true);
     });
 
     it("should return false if none of the users has a device", async () => {