Remove the default karaoke skin.

Because need to read the config from the karaoke skin.
So use tricky way to fix the test case broken.
Technically, should be better to use the skin transformer ;_;

osu.Game.Rulesets.Karaoke.Tests/Editor/TestSceneLayoutToolTip.cs

@@ -3,11 +3,15 @@
 
 using System;
 using System.Collections.Generic;
+using JetBrains.Annotations;
 using NUnit.Framework;
 using osu.Framework.Graphics;
+using osu.Game.IO;
 using osu.Game.Rulesets.Karaoke.Edit.Components.Cursor;
+using osu.Game.Rulesets.Karaoke.Extensions;
 using osu.Game.Rulesets.Karaoke.Objects;
 using osu.Game.Rulesets.Karaoke.Skinning;
+using osu.Game.Rulesets.Karaoke.Skinning.Elements;
 using osu.Game.Skinning;
 using osu.Game.Tests.Visual;
 
@@ -16,7 +20,7 @@ namespace osu.Game.Rulesets.Karaoke.Tests.Editor
     [TestFixture]
     public class TestSceneLayoutToolTip : OsuTestScene
     {
-        private readonly ISkin skin = new DefaultKaraokeSkin(null);
+        private ISkin skin = new TestingSkin(null);
         private LayoutToolTip toolTip = null!;
 
         [SetUp]
@@ -62,5 +66,37 @@ private void setTooltip(string testName, Action<Lyric> callBack)
                 toolTip.SetContent(singer);
             });
         }
+
+        /// <summary>
+        /// todo: it's a tricky way to create ruleset's own skin class.
+        /// should use generic skin like <see cref="LegacySkin"/> eventually.
+        /// </summary>
+        public class TestingSkin : KaraokeSkin
+        {
+            internal static readonly Guid DEFAULT_SKIN = new("FEC5A291-5709-11EC-9F10-0800200C9A66");
+
+            public static SkinInfo CreateInfo() => new()
+            {
+                ID = DEFAULT_SKIN,
+                Name = "karaoke! (default skin)",
+                Creator = "team karaoke!",
+                Protected = true,
+                InstantiationInfo = typeof(TestingSkin).GetInvariantInstantiationInfo()
+            };
+
+            public TestingSkin(IStorageResourceProvider? resources)
+                : this(CreateInfo(), resources)
+            {
+            }
+
+            [UsedImplicitly(ImplicitUseKindFlags.InstantiatedWithFixedConstructorSignature)]
+            public TestingSkin(SkinInfo skin, IStorageResourceProvider? resources)
+                : base(skin, resources)
+            {
+                DefaultElement[ElementType.LyricConfig] = LyricConfig.CreateDefault();
+                DefaultElement[ElementType.LyricStyle] = LyricStyle.CreateDefault();
+                DefaultElement[ElementType.NoteStyle] = NoteStyle.CreateDefault();
+            }
+        }
     }
 }

osu.Game.Rulesets.Karaoke.Tests/Screens/TestSceneKaraokeSkinEditor.cs

@@ -1,11 +1,16 @@
 // Copyright (c) andy840119 <[email protected]>. Licensed under the GPL Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
+using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Game.Database;
+using osu.Game.IO;
 using osu.Game.Rulesets.Karaoke.Beatmaps;
+using osu.Game.Rulesets.Karaoke.Extensions;
 using osu.Game.Rulesets.Karaoke.Screens.Skin;
 using osu.Game.Rulesets.Karaoke.Skinning;
+using osu.Game.Rulesets.Karaoke.Skinning.Elements;
 using osu.Game.Screens.Edit;
 using osu.Game.Skinning;
 
@@ -28,11 +33,43 @@ public class TestSceneKaraokeSkinEditor : ScreenTestScene<KaraokeSkinEditor>
         [BackgroundDependencyLoader]
         private void load(SkinManager skinManager)
         {
-            skinManager.CurrentSkinInfo.Value = DefaultKaraokeSkin.CreateInfo().ToLiveUnmanaged();
+            skinManager.CurrentSkinInfo.Value = TestingSkin.CreateInfo().ToLiveUnmanaged();
 
             karaokeSkin = skinManager.CurrentSkin.Value as KaraokeSkin;
         }
 
         protected override KaraokeSkinEditor CreateScreen() => new(karaokeSkin);
+
+        /// <summary>
+        /// todo: it's a tricky way to create ruleset's own skin class.
+        /// should use generic skin like <see cref="LegacySkin"/> eventually.
+        /// </summary>
+        public class TestingSkin : KaraokeSkin
+        {
+            internal static readonly Guid DEFAULT_SKIN = new("FEC5A291-5709-11EC-9F10-0800200C9A66");
+
+            public static SkinInfo CreateInfo() => new()
+            {
+                ID = DEFAULT_SKIN,
+                Name = "karaoke! (default skin)",
+                Creator = "team karaoke!",
+                Protected = true,
+                InstantiationInfo = typeof(TestingSkin).GetInvariantInstantiationInfo()
+            };
+
+            public TestingSkin(IStorageResourceProvider? resources)
+                : this(CreateInfo(), resources)
+            {
+            }
+
+            [UsedImplicitly(ImplicitUseKindFlags.InstantiatedWithFixedConstructorSignature)]
+            public TestingSkin(SkinInfo skin, IStorageResourceProvider? resources)
+                : base(skin, resources)
+            {
+                DefaultElement[ElementType.LyricConfig] = LyricConfig.CreateDefault();
+                DefaultElement[ElementType.LyricStyle] = LyricStyle.CreateDefault();
+                DefaultElement[ElementType.NoteStyle] = NoteStyle.CreateDefault();
+            }
+        }
     }
 }

osu.Game.Rulesets.Karaoke/Edit/Lyrics/LyricEditorSkin.cs

@@ -31,7 +31,7 @@ public class LyricEditorSkin : KaraokeSkin
             Name = "karaoke! (default editor skin)",
             Creator = "team karaoke!",
             Protected = true,
-            InstantiationInfo = typeof(DefaultKaraokeSkin).GetInvariantInstantiationInfo(),
+            InstantiationInfo = typeof(LyricEditorSkin).GetInvariantInstantiationInfo(),
         };
 
         public LyricEditorSkin(IStorageResourceProvider? resources)