Replace usages of is null with == null

osu.Game.Rulesets.Osu.Tests/Editor/TestSceneObjectMerging.cs

@@ -68,7 +68,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider created", () =>
             {
-                if (circle1 is null || circle2 is null || slider is null)
+                if (circle1 == null || circle2 == null || slider == null)
                     return false;
 
                 var controlPoints = slider.Path.ControlPoints;
@@ -111,7 +111,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider created", () =>
             {
-                if (slider1 is null || slider2 is null || slider1Path is null)
+                if (slider1 == null || slider2 == null || slider1Path == null)
                     return false;
 
                 var controlPoints1 = slider1Path.ControlPoints;
@@ -143,7 +143,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider end is at same completion for last slider", () =>
             {
-                if (slider1Path is null || slider2 is null)
+                if (slider1Path == null || slider2 == null)
                     return false;
 
                 var mergedSlider = (Slider)EditorBeatmap.SelectedHitObjects.First();
@@ -256,7 +256,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider created", () =>
             {
-                if (slider1 is null || slider2 is null || slider1Path is null)
+                if (slider1 == null || slider2 == null || slider1Path == null)
                     return false;
 
                 var controlPoints1 = slider1Path.ControlPoints;
@@ -288,7 +288,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider end is at same completion for last slider", () =>
             {
-                if (slider1Path is null || slider2 is null)
+                if (slider1Path == null || slider2 == null)
                     return false;
 
                 var mergedSlider = (Slider)EditorBeatmap.SelectedHitObjects.First();
@@ -322,7 +322,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider created", () =>
             {
-                if (slider1 is null || slider2 is null || slider1Path is null)
+                if (slider1 == null || slider2 == null || slider1Path == null)
                     return false;
 
                 var controlPoints1 = slider1Path.ControlPoints;
@@ -354,7 +354,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddAssert("slider end is at same completion for last slider", () =>
             {
-                if (slider1Path is null || slider2 is null)
+                if (slider1Path == null || slider2 == null)
                     return false;
 
                 var mergedSlider = (Slider)EditorBeatmap.SelectedHitObjects.First();

osu.Game.Rulesets.Osu.Tests/Editor/TestSceneSliderSplitting.cs

@@ -178,7 +178,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
 
             AddStep("add hitsounds", () =>
             {
-                if (slider is null) return;
+                if (slider == null) return;
 
                 sample = new HitSampleInfo("hitwhistle", HitSampleInfo.BANK_SOFT, volume: 70);
                 slider.Samples.Add(sample.With());
@@ -228,7 +228,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
         {
             AddStep($"move mouse to control point {index}", () =>
             {
-                if (slider is null || visualiser is null) return;
+                if (slider == null || visualiser == null) return;
 
                 Vector2 position = slider.Path.ControlPoints[index].Position + slider.Position;
                 InputManager.MoveMouseTo(visualiser.Pieces[0].Parent!.ToScreenSpace(position));
@@ -239,7 +239,7 @@ namespace osu.Game.Rulesets.Osu.Tests.Editor
         {
             AddStep($"click context menu item \"{contextMenuText}\"", () =>
             {
-                if (visualiser is null) return;
+                if (visualiser == null) return;
 
                 MenuItem? item = visualiser.ContextMenuItems?.FirstOrDefault(menuItem => menuItem.Text.Value == contextMenuText);
 

osu.Game.Rulesets.Osu/Edit/Blueprints/Sliders/SliderSelectionBlueprint.cs

@@ -311,7 +311,7 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders
 
             foreach (var splitPoint in controlPointsToSplitAt)
             {
-                if (splitPoint == controlPoints[0] || splitPoint == controlPoints[^1] || splitPoint.Type is null)
+                if (splitPoint == controlPoints[0] || splitPoint == controlPoints[^1] || splitPoint.Type == null)
                     continue;
 
                 // Split off the section of slider before this control point so the remaining control points to split are in the latter part of the slider.

osu.Game/Overlays/Mods/ModSelectOverlay.cs

@@ -781,7 +781,7 @@ namespace osu.Game.Overlays.Mods
         /// </remarks>>
         public bool OnPressed(KeyBindingPressEvent<PlatformAction> e)
         {
-            if (e.Repeat || e.Action != PlatformAction.SelectAll || SelectAllModsButton is null)
+            if (e.Repeat || e.Action != PlatformAction.SelectAll || SelectAllModsButton == null)
                 return false;
 
             SelectAllModsButton.TriggerClick();

osu.Game/Rulesets/Objects/Legacy/ConvertHitObjectParser.cs

@@ -347,7 +347,7 @@ namespace osu.Game.Rulesets.Objects.Legacy
             // Edge-case rules (to match stable).
             if (type == PathType.PERFECT_CURVE)
             {
-                int endPointLength = endPoint is null ? 0 : 1;
+                int endPointLength = endPoint == null ? 0 : 1;
 
                 if (vertices.Length + endPointLength != 3)
                     type = PathType.BEZIER;

osu.Game/Rulesets/Objects/PathControlPoint.cs

@@ -77,7 +77,7 @@ namespace osu.Game.Rulesets.Objects
 
         public bool Equals(PathControlPoint other) => Position == other?.Position && Type == other.Type;
 
-        public override string ToString() => type is null
+        public override string ToString() => type == null
             ? $"Position={Position}"
             : $"Position={Position}, Type={type}";
     }

osu.Game/Rulesets/Objects/SliderPathExtensions.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Rulesets.Objects
         {
             var controlPoints = sliderPath.ControlPoints;
 
-            var inheritedLinearPoints = controlPoints.Where(p => sliderPath.PointsInSegment(p)[0].Type == PathType.LINEAR && p.Type is null).ToList();
+            var inheritedLinearPoints = controlPoints.Where(p => sliderPath.PointsInSegment(p)[0].Type == PathType.LINEAR && p.Type == null).ToList();
 
             // Inherited points after a linear point, as well as the first control point if it inherited,
             // should be treated as linear points, so their types are temporarily changed to linear.
@@ -53,7 +53,7 @@ namespace osu.Game.Rulesets.Objects
             inheritedLinearPoints.ForEach(p => p.Type = null);
 
             // Recalculate middle perfect curve control points at the end of the slider path.
-            if (controlPoints.Count >= 3 && controlPoints[^3].Type == PathType.PERFECT_CURVE && controlPoints[^2].Type is null && segmentEnds.Any())
+            if (controlPoints.Count >= 3 && controlPoints[^3].Type == PathType.PERFECT_CURVE && controlPoints[^2].Type == null && segmentEnds.Any())
             {
                 double lastSegmentStart = segmentEnds.Length > 1 ? segmentEnds[^2] : 0;
                 double lastSegmentEnd = segmentEnds[^1];

osu.Game/Rulesets/UI/ModIcon.cs

@@ -177,7 +177,7 @@ namespace osu.Game.Rulesets.UI
             modAcronym.Text = value.Acronym;
             modIcon.Icon = value.Icon ?? FontAwesome.Solid.Question;
 
-            if (value.Icon is null)
+            if (value.Icon == null)
             {
                 modIcon.FadeOut();
                 modAcronym.FadeIn();