From ca92ad715a9a11bd772b2f53d04f3cb5a8e13431 Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Mon, 22 Feb 2021 13:32:54 +0900
Subject: [PATCH] Add test

---
 osu.Game.Rulesets.Osu/Mods/OsuModTraceable.cs |  2 +-
 .../TestSceneMultiplayerMatchSongSelect.cs    | 28 +++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/osu.Game.Rulesets.Osu/Mods/OsuModTraceable.cs b/osu.Game.Rulesets.Osu/Mods/OsuModTraceable.cs
index df0a41455f..4b0939db16 100644
--- a/osu.Game.Rulesets.Osu/Mods/OsuModTraceable.cs
+++ b/osu.Game.Rulesets.Osu/Mods/OsuModTraceable.cs
@@ -11,7 +11,7 @@ using osu.Game.Rulesets.Osu.Skinning.Default;
 
 namespace osu.Game.Rulesets.Osu.Mods
 {
-    internal class OsuModTraceable : ModWithVisibilityAdjustment
+    public class OsuModTraceable : ModWithVisibilityAdjustment
     {
         public override string Name => "Traceable";
         public override string Acronym => "TC";
diff --git a/osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.cs b/osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.cs
index 95c333e9f4..faa5d9e6fc 100644
--- a/osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.cs
+++ b/osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayerMatchSongSelect.cs
@@ -7,17 +7,23 @@ using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
+using osu.Framework.Bindables;
 using osu.Framework.Extensions;
+using osu.Framework.Extensions.TypeExtensions;
 using osu.Framework.Platform;
 using osu.Framework.Screens;
+using osu.Framework.Testing;
 using osu.Framework.Utils;
 using osu.Game.Beatmaps;
+using osu.Game.Overlays.Mods;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Catch;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.Taiko;
 using osu.Game.Rulesets.Taiko.Mods;
+using osu.Game.Screens.OnlinePlay;
 using osu.Game.Screens.OnlinePlay.Multiplayer;
 using osu.Game.Screens.Select;
 
@@ -137,8 +143,30 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddAssert("mods not changed", () => SelectedMods.Value.Single() is TaikoModDoubleTime);
         }
 
+        [TestCase(typeof(OsuModHidden), typeof(OsuModHidden))] // Same mod.
+        [TestCase(typeof(OsuModHidden), typeof(OsuModTraceable))] // Incompatible.
+        public void TestAllowedModDeselectedWhenRequired(Type allowedMod, Type requiredMod)
+        {
+            AddStep($"select {allowedMod.ReadableName()} as allowed", () => songSelect.FreeMods.Value = new[] { (Mod)Activator.CreateInstance(allowedMod) });
+            AddStep($"select {requiredMod.ReadableName()} as required", () => songSelect.Mods.Value = new[] { (Mod)Activator.CreateInstance(requiredMod) });
+
+            AddAssert("freemods empty", () => songSelect.FreeMods.Value.Count == 0);
+            assertHasFreeModButton(allowedMod, false);
+            assertHasFreeModButton(requiredMod, false);
+        }
+
+        private void assertHasFreeModButton(Type type, bool hasButton = true)
+        {
+            AddAssert($"{type.ReadableName()} {(hasButton ? "displayed" : "not displayed")} in freemod overlay",
+                () => songSelect.ChildrenOfType<FreeModSelectOverlay>().Single().ChildrenOfType<ModButton>().All(b => b.Mod.GetType() != type));
+        }
+
         private class TestMultiplayerMatchSongSelect : MultiplayerMatchSongSelect
         {
+            public new Bindable<IReadOnlyList<Mod>> Mods => base.Mods;
+
+            public new Bindable<IReadOnlyList<Mod>> FreeMods => base.FreeMods;
+
             public new BeatmapCarousel Carousel => base.Carousel;
         }
     }