Nullability fixes for Avalonia.Diagnostics

src/Avalonia.Controls/Primitives/OverlayPopupHost.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using Avalonia.Reactive;
 using Avalonia.Controls.Primitives.PopupPositioning;
 using Avalonia.Interactivity;
 using Avalonia.Media;
@@ -18,8 +17,8 @@ namespace Avalonia.Controls.Primitives
             PopupRoot.TransformProperty.AddOwner<OverlayPopupHost>();
 
         private readonly OverlayLayer _overlayLayer;
-        private PopupPositionerParameters _positionerParameters = new PopupPositionerParameters();
-        private ManagedPopupPositioner _positioner;
+        private readonly ManagedPopupPositioner _positioner;
+        private PopupPositionerParameters _positionerParameters;
         private Point _lastRequestedPosition;
         private bool _shown;
 
@@ -29,13 +28,16 @@ namespace Avalonia.Controls.Primitives
             _positioner = new ManagedPopupPositioner(this);
         }
 
+        /// <inheritdoc />
         public void SetChild(Control? control)
         {
             Content = control;
         }
 
+        /// <inheritdoc />
         public Visual? HostedVisualTreeRoot => null;
 
+        /// <inheritdoc />
         public Transform? Transform
         {
             get => GetValue(TransformProperty);
@@ -48,23 +50,27 @@ namespace Avalonia.Controls.Primitives
             set { /* Not currently supported in overlay popups */ }
         }
 
+        /// <inheritdoc />
         protected internal override Interactive? InteractiveParent => (Interactive?)VisualParent;
 
+        /// <inheritdoc />
         public void Dispose() => Hide();
 
-
+        /// <inheritdoc />
         public void Show()
         {
             _overlayLayer.Children.Add(this);
             _shown = true;
         }
 
+        /// <inheritdoc />
         public void Hide()
         {
             _overlayLayer.Children.Remove(this);
             _shown = false;
         }
 
+        /// <inheritdoc />
         public void ConfigurePosition(Visual target, PlacementMode placement, Point offset,
             PopupAnchor anchor = PopupAnchor.None, PopupGravity gravity = PopupGravity.None,
             PopupPositionerConstraintAdjustment constraintAdjustment = PopupPositionerConstraintAdjustment.All,
@@ -75,6 +81,7 @@ namespace Avalonia.Controls.Primitives
             UpdatePosition();
         }
 
+        /// <inheritdoc />
         protected override Size ArrangeOverride(Size finalSize)
         {
             if (_positionerParameters.Size != finalSize)
@@ -123,17 +130,18 @@ namespace Avalonia.Controls.Primitives
        
         public static IPopupHost CreatePopupHost(Visual target, IAvaloniaDependencyResolver? dependencyResolver)
         {
-            var platform = TopLevel.GetTopLevel(target)?.PlatformImpl?.CreatePopup();
-            if (platform != null)
-                return new PopupRoot((TopLevel)target.GetVisualRoot()!, platform, dependencyResolver);
-            
-            var overlayLayer = OverlayLayer.GetOverlayLayer(target);
-            if (overlayLayer == null)
-                throw new InvalidOperationException(
-                    "Unable to create IPopupImpl and no overlay layer is found for the target control");
+            if (TopLevel.GetTopLevel(target) is { } topLevel && topLevel.PlatformImpl?.CreatePopup() is { } popupImpl)
+            {
+                return new PopupRoot(topLevel, popupImpl, dependencyResolver);
+            }
 
+            if (OverlayLayer.GetOverlayLayer(target) is { } overlayLayer)
+            {
+                return new OverlayPopupHost(overlayLayer);
+            }
 
-            return new OverlayPopupHost(overlayLayer);
+            throw new InvalidOperationException(
+                "Unable to create IPopupImpl and no overlay layer is found for the target control");
         }
     }
 }

src/Avalonia.Controls/TopLevel.cs

@@ -402,7 +402,7 @@ namespace Avalonia.Controls
         /// <returns>The TopLevel</returns>
         public static TopLevel? GetTopLevel(Visual? visual)
         {
-            return visual == null ? null : visual.VisualRoot as TopLevel;
+            return visual?.VisualRoot as TopLevel;
         }
         
         protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)

src/Avalonia.Diagnostics/Diagnostics/KeyGestureExtesions.cs

@@ -3,10 +3,9 @@ using Avalonia.Input.Raw;
 
 namespace Avalonia.Diagnostics
 {
-    static class KeyGestureExtesions
+    internal static class KeyGestureExtesions
     {
         public static bool Matches(this KeyGesture gesture, RawKeyEventArgs keyEvent) =>
-            keyEvent != null &&
             (KeyModifiers)(keyEvent.Modifiers & RawInputModifiers.KeyboardMask) == gesture.KeyModifiers &&
                 ResolveNumPadOperationKey(keyEvent.Key) == ResolveNumPadOperationKey(gesture.Key);