Refactor star "DifficultyRangeFilterControl" into generic range slider class

osu.Game.Tests/Visual/UserInterface/TestSceneRangeSlider.cs

@@ -0,0 +1,60 @@
+// 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 NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Game.Graphics.UserInterface;
+using osu.Game.Overlays;
+using osuTK;
+
+namespace osu.Game.Tests.Visual.UserInterface
+{
+    public class TestSceneRangeSlider : OsuTestScene
+    {
+        [Cached]
+        private OverlayColourProvider colourProvider = new OverlayColourProvider(OverlayColourScheme.Purple);
+
+        private readonly BindableNumber<double> customStart = new BindableNumber<double>
+        {
+            MinValue = 0,
+            MaxValue = 100,
+            Precision = 0.001f
+        };
+
+        private readonly BindableNumber<double> customEnd = new BindableNumber<double>(100)
+        {
+            MinValue = 0,
+            MaxValue = 100,
+            Precision = 0.1f
+        };
+
+        [Test]
+        public void TestBasic()
+        {
+            AddStep("create Control", () => Child = new RangeSlider
+            {
+                Width = 200,
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+                Scale = new Vector2(3),
+                LowerBound = customStart,
+                UpperBound = customEnd,
+                TooltipSuffix = "suffix",
+                NubWidth = Nub.HEIGHT * 2,
+                DefaultStringLowerBound = "Start",
+                DefaultStringUpperBound = "End"
+            });
+            AddStep("Test Range", () =>
+            {
+                customStart.Value = 50;
+                customEnd.Value = 75;
+            });
+            AddStep("Test nub pushing", () =>
+            {
+                customStart.Value = 90;
+            });
+        }
+    }
+}