Use SlidingSyncUntilMembership for subscription test

tests-e2e/membership_transitions_test.go

@@ -5,10 +5,9 @@ import (
 	"testing"
 	"time"
 
-	"github.com/tidwall/gjson"
-
 	"github.com/matrix-org/sliding-sync/sync3"
 	"github.com/matrix-org/sliding-sync/testutils/m"
+	"github.com/tidwall/gjson"
 )
 
 func TestRoomStateTransitions(t *testing.T) {
@@ -627,32 +626,7 @@ func TestHeroesOnMembershipChanges(t *testing.T) {
 		subRoomID := alice.CreateRoom(t, map[string]interface{}{"preset": "public_chat"})
 		bob.JoinRoom(t, subRoomID, []string{})
 
-		res := alice.SlidingSyncUntil(t, "", sync3.Request{
-			RoomSubscriptions: map[string]sync3.RoomSubscription{
-				subRoomID: {
-					TimelineLimit: 10,
-					Heroes:        &boolTrue,
-				},
-			},
-		}, func(response *sync3.Response) error {
-			r, ok := response.Rooms[subRoomID]
-			if !ok {
-				return fmt.Errorf("room %q not in response", subRoomID)
-			}
-			// wait for bob to be joined
-			for _, ev := range r.Timeline {
-				if gjson.GetBytes(ev, "type").Str != "m.room.member" {
-					continue
-				}
-				if gjson.GetBytes(ev, "state_key").Str != bob.UserID {
-					continue
-				}
-				if gjson.GetBytes(ev, "content.membership").Str == "join" {
-					return nil
-				}
-			}
-			return fmt.Errorf("%s is not joined to room %q", bob.UserID, subRoomID)
-		})
+		res := alice.SlidingSyncUntilMembership(t, "", subRoomID, bob, "join")
 		if c := len(res.Rooms[subRoomID].Heroes); c > 1 {
 			t.Errorf("expected 1 room hero, got %d", c)
 		}