From 855fff1486477eb490ed851a33a26be57b96c095 Mon Sep 17 00:00:00 2001
From: Salman Ahmed <frenzibyte@gmail.com>
Date: Mon, 16 Aug 2021 12:47:56 +0300
Subject: [PATCH 1/2] Fix `DifficultyAdjustSettingsControl.SliderControl` not
 following up with the current pattern

This was causing any `ValueChanged` event bind (such as the one in
`SettingsItem` to invoke `SettingsChanged`) to be overwritten when
`Current` is set afterwards.
---
 osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs b/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
index 067657159b..186514e868 100644
--- a/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
+++ b/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
@@ -91,7 +91,13 @@ namespace osu.Game.Rulesets.Mods
         {
             // This is required as SettingsItem relies heavily on this bindable for internal use.
             // The actual update flow is done via the bindable provided in the constructor.
-            public Bindable<float?> Current { get; set; } = new Bindable<float?>();
+            private readonly BindableWithCurrent<float?> current = new BindableWithCurrent<float?>();
+
+            public Bindable<float?> Current
+            {
+                get => current.Current;
+                set => current.Current = value;
+            }
 
             public SliderControl(BindableNumber<float> currentNumber)
             {

From 6653a78e659774213635568d5fd2bdcc7d693170 Mon Sep 17 00:00:00 2001
From: Salman Ahmed <frenzibyte@gmail.com>
Date: Mon, 16 Aug 2021 12:48:49 +0300
Subject: [PATCH 2/2] Add test coverage

---
 .../TestSceneModDifficultyAdjustSettings.cs   | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/osu.Game.Tests/Visual/UserInterface/TestSceneModDifficultyAdjustSettings.cs b/osu.Game.Tests/Visual/UserInterface/TestSceneModDifficultyAdjustSettings.cs
index e0d76b3e4a..f8652573f4 100644
--- a/osu.Game.Tests/Visual/UserInterface/TestSceneModDifficultyAdjustSettings.cs
+++ b/osu.Game.Tests/Visual/UserInterface/TestSceneModDifficultyAdjustSettings.cs
@@ -1,8 +1,10 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
@@ -174,6 +176,60 @@ namespace osu.Game.Tests.Visual.UserInterface
             checkBindableAtValue("Circle Size", null);
         }
 
+        [Test]
+        public void TestModSettingChangeTracker()
+        {
+            ModSettingChangeTracker tracker = null;
+            Queue<Mod> settingsChangedQueue = null;
+
+            setBeatmapWithDifficultyParameters(5);
+
+            AddStep("add mod settings change tracker", () =>
+            {
+                settingsChangedQueue = new Queue<Mod>();
+
+                tracker = new ModSettingChangeTracker(modDifficultyAdjust.Yield())
+                {
+                    SettingChanged = settingsChangedQueue.Enqueue
+                };
+            });
+
+            AddAssert("no settings changed", () => settingsChangedQueue.Count == 0);
+
+            setSliderValue("Circle Size", 3);
+
+            settingsChangedFired();
+
+            setSliderValue("Circle Size", 5);
+            checkBindableAtValue("Circle Size", 5);
+
+            settingsChangedFired();
+
+            AddStep("reset mod settings", () => modDifficultyAdjust.CircleSize.SetDefault());
+            checkBindableAtValue("Circle Size", null);
+
+            settingsChangedFired();
+
+            setExtendedLimits(true);
+
+            settingsChangedFired();
+
+            AddStep("dispose tracker", () =>
+            {
+                tracker.Dispose();
+                tracker = null;
+            });
+
+            void settingsChangedFired()
+            {
+                AddAssert("setting changed event fired", () =>
+                {
+                    settingsChangedQueue.Dequeue();
+                    return settingsChangedQueue.Count == 0;
+                });
+            }
+        }
+
         private void resetToDefault(string name)
         {
             AddStep($"Reset {name} to default", () =>