From 9b77b958e00a49b666a73555e779700a188409e2 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Fri, 30 May 2025 15:48:41 +0900
Subject: [PATCH] Add failing tests showing carousel incorrectly requesting
 start when traversing single items

---
 .../SongSelectV2/BeatmapCarouselTestScene.cs  | 20 +++++++
 .../TestSceneBeatmapCarouselNoGrouping.cs     | 52 +++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/osu.Game.Tests/Visual/SongSelectV2/BeatmapCarouselTestScene.cs b/osu.Game.Tests/Visual/SongSelectV2/BeatmapCarouselTestScene.cs
index f9f7f3e89c..9c109bc782 100644
--- a/osu.Game.Tests/Visual/SongSelectV2/BeatmapCarouselTestScene.cs
+++ b/osu.Game.Tests/Visual/SongSelectV2/BeatmapCarouselTestScene.cs
@@ -191,6 +191,12 @@ namespace osu.Game.Tests.Visual.SongSelectV2
         protected void CheckNoSelection() => AddAssert("has no selection", () => Carousel.CurrentSelection, () => Is.Null);
         protected void CheckHasSelection() => AddAssert("has selection", () => Carousel.CurrentSelection, () => Is.Not.Null);
 
+        protected void CheckRequestPresentCount(int expected) =>
+            AddAssert($"check present count is {expected}", () => Carousel.RequestPresentBeatmapCount, () => Is.EqualTo(expected));
+
+        protected void CheckActivationCount(int expected) =>
+            AddAssert($"check activation count is {expected}", () => Carousel.ActivationCount, () => Is.EqualTo(expected));
+
         protected void CheckDisplayedBeatmapsCount(int expected)
         {
             AddAssert($"{expected} diffs displayed", () => Carousel.MatchedBeatmapsCount, () => Is.EqualTo(expected));
@@ -375,6 +381,9 @@ namespace osu.Game.Tests.Visual.SongSelectV2
 
         public partial class TestBeatmapCarousel : BeatmapCarousel
         {
+            public int ActivationCount { get; private set; }
+            public int RequestPresentBeatmapCount { get; private set; }
+
             public int FilterDelay = 0;
 
             public IEnumerable<BeatmapInfo> PostFilterBeatmaps = null!;
@@ -385,6 +394,17 @@ namespace osu.Game.Tests.Visual.SongSelectV2
             public new BeatmapSetInfo? ExpandedBeatmapSet => base.ExpandedBeatmapSet;
             public new GroupDefinition? ExpandedGroup => base.ExpandedGroup;
 
+            public TestBeatmapCarousel()
+            {
+                RequestPresentBeatmap = _ => RequestPresentBeatmapCount++;
+            }
+
+            protected override void HandleItemActivated(CarouselItem item)
+            {
+                ActivationCount++;
+                base.HandleItemActivated(item);
+            }
+
             protected override async Task<IEnumerable<CarouselItem>> FilterAsync(bool clearExistingPanels = false)
             {
                 var items = await base.FilterAsync(clearExistingPanels);
diff --git a/osu.Game.Tests/Visual/SongSelectV2/TestSceneBeatmapCarouselNoGrouping.cs b/osu.Game.Tests/Visual/SongSelectV2/TestSceneBeatmapCarouselNoGrouping.cs
index e72a373d63..d0ecb2c05a 100644
--- a/osu.Game.Tests/Visual/SongSelectV2/TestSceneBeatmapCarouselNoGrouping.cs
+++ b/osu.Game.Tests/Visual/SongSelectV2/TestSceneBeatmapCarouselNoGrouping.cs
@@ -190,6 +190,58 @@ namespace osu.Game.Tests.Visual.SongSelectV2
             WaitForSelection(4, 0);
         }
 
+        [Test]
+        public void TestSingleItemTraversal()
+        {
+            CheckNoSelection();
+            AddBeatmaps(1, 3);
+
+            WaitForSelection(0, 0);
+            CheckActivationCount(0);
+
+            SelectNextGroup();
+            WaitForSelection(0, 0);
+
+            // In the case of a grouped beatmap set, the header gets activated and re-selects the recommended difficulty.
+            // This is probably fine.
+            CheckActivationCount(1);
+            // We don't want it to request present though, which would start gameplay.
+            CheckRequestPresentCount(0);
+
+            SelectPrevGroup();
+            WaitForSelection(0, 0);
+
+            CheckActivationCount(1);
+            CheckRequestPresentCount(0);
+        }
+
+        [Test]
+        public void TestSingleItemTraversal_DifficultySplit()
+        {
+            SortBy(SortMode.Difficulty);
+
+            CheckNoSelection();
+            AddBeatmaps(1, 1);
+
+            WaitForSelection(0, 0);
+            CheckActivationCount(0);
+
+            SelectNextGroup();
+            WaitForSelection(0, 0);
+
+            // In the case of a grouped beatmap set, the header gets activated and re-selects the recommended difficulty.
+            // This is probably fine.
+            CheckActivationCount(0);
+            // We don't want it to request present though, which would start gameplay.
+            CheckRequestPresentCount(0);
+
+            SelectPrevGroup();
+            WaitForSelection(0, 0);
+
+            CheckActivationCount(0);
+            CheckRequestPresentCount(0);
+        }
+
         [Test]
         public void TestEmptyTraversal()
         {