Enable nullability in various test projects (#20374)

* Enable nullability in RenderTests

* Enable nullability in LeakTests

* Enable nullability in Skia.UnitTests

* Enable nullability in Generators.Tests

* Enable nullability in DesignerSupport.Tests

* Enable nullability in Build.Tasks.UnitTests

tests/Avalonia.Build.Tasks.UnitTest/Avalonia.Build.Tasks.UnitTest.csproj

@@ -14,6 +14,7 @@
   <Import Project="..\..\build\HarfBuzzSharp.props" />
   <Import Project="..\..\build\XUnit.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
   <ItemGroup>
     <Content Include="..\TestFiles\BuildTasks\PInvoke\bin\$(Configuration)\$(AvsCurrentTargetFramework)\PInvoke.dll" Link="Assets\PInvoke.dll">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>

tests/Avalonia.Build.Tasks.UnitTest/UnitTestBuildEngine.cs

@@ -40,11 +40,11 @@ internal class UnitTestBuildEngine : IBuildEngine, IDisposable
 
     public bool ContinueOnError { get; }
 
-    public int LineNumberOfTaskNode { get; }
+    public int LineNumberOfTaskNode => 0;
 
-    public int ColumnNumberOfTaskNode { get; }
+    public int ColumnNumberOfTaskNode => 0;
 
-    public string ProjectFileOfTaskNode { get; }
+    public string ProjectFileOfTaskNode => string.Empty;
 
     public IReadOnlyList<UnitTestBuildEngineMessage> Errors => _errors;
 

tests/Avalonia.DesignerSupport.TestApp/Avalonia.DesignerSupport.TestApp.csproj

@@ -25,4 +25,5 @@
     <ProjectReference Include="..\..\src\Avalonia.Desktop\Avalonia.Desktop.csproj" />
   </ItemGroup>
   <Import Project="..\..\build\BuildTargets.targets" />
+  <Import Project="..\..\build\NullableEnable.props" />
 </Project>

tests/Avalonia.DesignerSupport.Tests/Avalonia.DesignerSupport.Tests.csproj

@@ -9,6 +9,7 @@
   <Import Project="..\..\build\XUnit.props" />
   <Import Project="..\..\build\Rx.props" />
   <Import Project="..\..\build\Microsoft.Reactive.Testing.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
   <ItemGroup>
     <ProjectReference Include="..\..\src\Avalonia.Controls\Avalonia.Controls.csproj" />
     <ProjectReference Include="..\..\src\Avalonia.DesignerSupport\Avalonia.DesignerSupport.csproj" />

tests/Avalonia.DesignerSupport.Tests/DesignerSupportTests.cs

@@ -82,7 +82,7 @@ namespace Avalonia.DesignerSupport.Tests
             var sessionId = Guid.NewGuid();
             long handle = 0;
             bool success = false;
-            string error = null;
+            string? error = null;
 
             var resultMessageReceivedToken = new CancellationTokenSource();
 

tests/Avalonia.DesignerSupport.Tests/Helpers.cs

@@ -1,15 +1,14 @@
 using System;
 using System.Collections;
-using System.Collections.Generic;
 using System.Linq;
 
 namespace Avalonia.DesignerSupport.Tests
 {
     static class Helpers
     {
-        public static void StructDiff(object parsed, object expected) => StructDiff(parsed, expected, "{root}");
+        public static void StructDiff(object? parsed, object? expected) => StructDiff(parsed, expected, "{root}");
 
-        static void StructDiff(object parsed, object expected, string path)
+        static void StructDiff(object? parsed, object? expected, string path)
         {
             if (parsed == null && expected == null)
                 return;
@@ -17,7 +16,7 @@ namespace Avalonia.DesignerSupport.Tests
                 throw new Exception(
                     $"{path}: Null mismatch: {(parsed == null ? "null" : "not-null")}  {(expected == null ? "null" : "not-null")}");
             
-            if (parsed.GetType() != expected.GetType())
+            if (parsed!.GetType() != expected!.GetType())
                 throw new Exception($"{path}: Type mismatch: {parsed.GetType()} {expected.GetType()}");
 
             if (parsed is string || parsed.GetType().IsPrimitive)

tests/Avalonia.DesignerSupport.Tests/RemoteProtocolTests.cs

@@ -21,27 +21,29 @@ namespace Avalonia.DesignerSupport.Tests
         private const int TimeoutInMs = 1000;
 
         private readonly List<IDisposable> _disposables = new List<IDisposable>();
-        private IAvaloniaRemoteTransportConnection _server;
+        private IAvaloniaRemoteTransportConnection? _server;
-        private IAvaloniaRemoteTransportConnection _client;
+        private IAvaloniaRemoteTransportConnection? _client;
         private BlockingCollection<object> _serverMessages = new BlockingCollection<object>();
         private BlockingCollection<object> _clientMessages = new BlockingCollection<object>();
-        private SynchronizationContext _originalContext;
+        private SynchronizationContext? _originalContext;
 
 
         class DisabledSyncContext : SynchronizationContext
         {
-            public override void Post(SendOrPostCallback d, object state)
+            public override void Post(SendOrPostCallback d, object? state)
             {
                 throw new InvalidCastException("Not allowed");
             }
 
-            public override void Send(SendOrPostCallback d, object state)
+            public override void Send(SendOrPostCallback d, object? state)
             {
                 throw new InvalidCastException("Not allowed");
             }
         }
-        
+
-        void Init(IMessageTypeResolver clientResolver = null, IMessageTypeResolver serverResolver = null)
+        [MemberNotNull(nameof(_server))]
+        [MemberNotNull(nameof(_client))]
+        void Init(IMessageTypeResolver? clientResolver = null, IMessageTypeResolver? serverResolver = null)
         {
             _originalContext = SynchronizationContext.Current;
             SynchronizationContext.SetSynchronizationContext(new DisabledSyncContext());
@@ -63,6 +65,7 @@ namespace Avalonia.DesignerSupport.Tests
             _disposables.Add(_client);
             _client.OnMessage += (_, m) => _clientMessages.Add(m);
             tcs.Task.Wait();
+            Assert.NotNull(_server);
             _disposables.Add(_server);
             _server.OnMessage += (_, m) => _serverMessages.Add(m);
 
@@ -95,8 +98,10 @@ namespace Avalonia.DesignerSupport.Tests
             {
                 if (t.IsArray)
                 {
-                    var arr = Array.CreateInstance(t.GetElementType(), 1);
+                    var elementType = t.GetElementType();
-                    ((IList)arr)[0] = GetRandomValue(t.GetElementType(), pathInfo);
+                    Assert.NotNull(elementType);
+                    var arr = Array.CreateInstance(elementType, 1);
+                    ((IList)arr)[0] = GetRandomValue(elementType, pathInfo);
                     return arr;
                 }
 
@@ -217,12 +222,12 @@ namespace Avalonia.DesignerSupport.Tests
         public double Width { get; set; }
         
         public int SomeNewProperty { get; set; }
-        public int[] SomeArrayProperty { get; set; }
+        public int[]? SomeArrayProperty { get; set; }
         public class SubObject
         {
             public int Foo { get; set; }
         }
-        public SubObject SubObjectProperty { get; set; }
+        public SubObject? SubObjectProperty { get; set; }
         public double Height { get; set; }
     }
 }

tests/Avalonia.Generators.Tests/Avalonia.Generators.Tests.csproj

@@ -21,4 +21,5 @@
   <Import Project="..\..\build\UnitTests.NetCore.targets" />
   <Import Project="..\..\build\XUnit.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
 </Project>

tests/Avalonia.Generators.Tests/Views/View.cs

@@ -36,7 +36,7 @@ public static class View
         return await reader.ReadToEndAsync();
     }
 
-    public static CSharpCompilation CreateAvaloniaCompilation(string excludedPattern = null)
+    public static CSharpCompilation CreateAvaloniaCompilation(string? excludedPattern = null)
     {
         var compilation = CSharpCompilation
             .Create("AvaloniaLib", options: new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary))
@@ -73,4 +73,4 @@ public static class View
             CSharpSyntaxTree.ParseText(
                 "using Avalonia.Controls;" +
                 "namespace Sample.App { public class BaseView<TViewModel> : UserControl { } }"));
-}
+}

tests/Avalonia.LeakTests/Avalonia.LeakTests.csproj

@@ -6,6 +6,7 @@
   <Import Project="..\..\build\XUnit.props" />
   <Import Project="..\..\build\NetFX.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
   <ItemGroup>
     <ProjectReference Include="..\..\src\Avalonia.Controls.ColorPicker\Avalonia.Controls.ColorPicker.csproj" />
     <ProjectReference Include="..\..\src\Markup\Avalonia.Markup.Xaml\Avalonia.Markup.Xaml.csproj" />

tests/Avalonia.LeakTests/AvaloniaObjectTests.cs

@@ -1,6 +1,4 @@
-#nullable enable
+using System;
-
-using System;
 using System.ComponentModel;
 using System.Reactive.Subjects;
 using System.Runtime.CompilerServices;

tests/Avalonia.LeakTests/ControlTests.cs

@@ -1,5 +1,3 @@
-#nullable enable
-
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;

tests/Avalonia.RenderTests/ManualRenderTimer.cs

@@ -1,14 +1,12 @@
 using Avalonia.Rendering;
-using System.Threading.Tasks;
 using System;
 
 namespace Avalonia.Skia.RenderTests
 {
     public class ManualRenderTimer : IRenderTimer
     {
-        public event Action<TimeSpan> Tick;
+        public event Action<TimeSpan>? Tick;
         public bool RunsInBackground => false;
         public void TriggerTick() => Tick?.Invoke(TimeSpan.Zero);
-        public Task TriggerBackgroundTick() => Task.Run(TriggerTick);
     }
 }

tests/Avalonia.RenderTests/TestBase.cs

@@ -92,7 +92,7 @@ namespace Avalonia.Skia.RenderTests
             }
         }
 
-        protected void CompareImagesNoRenderer([CallerMemberName] string testName = "", string expectedName = null)
+        protected void CompareImagesNoRenderer([CallerMemberName] string testName = "", string? expectedName = null)
         {
             var expectedPath = Path.Combine(OutputPath, (expectedName ?? testName) + ".expected.png");
             var actualPath = Path.Combine(OutputPath, testName + ".out.png");

tests/Avalonia.RenderTests/TestRenderHelper.cs

@@ -44,6 +44,8 @@ static class TestRenderHelper
     public static Task RenderToFile(Control target, string path, bool immediate, double dpi = 96)
     {
         var dir = Path.GetDirectoryName(path);
+        Assert.NotNull(dir);
+
         if (!Directory.Exists(dir)) 
             Directory.CreateDirectory(dir);
         
@@ -119,24 +121,23 @@ static class TestRenderHelper
     {
         var path = Directory.GetCurrentDirectory();
 
-        while (path.Length > 0 && Path.GetFileName(path) != "tests")
+        while (!string.IsNullOrEmpty(path) && Path.GetFileName(path) != "tests")
         {
             path = Path.GetDirectoryName(path);
         }
 
+        Assert.NotNull(path);
         return path;
     }
     
     private class TestDispatcherImpl : IDispatcherImpl
     {
-        public bool CurrentThreadIsLoopThread => MainThread.ManagedThreadId == Thread.CurrentThread.ManagedThreadId;
+        public bool CurrentThreadIsLoopThread => MainThread?.ManagedThreadId == Thread.CurrentThread.ManagedThreadId;
 
-        public Thread MainThread { get; set; }
+        public Thread? MainThread { get; set; }
 
-#pragma warning disable 67
+        public event Action? Signaled { add { } remove { } }
-        public event Action Signaled;
+        public event Action? Timer { add { } remove { } }
-        public event Action Timer;
-#pragma warning restore 67
 
         public void Signal()
         {

tests/Avalonia.RenderTests/TestRenderRoot.cs

@@ -12,7 +12,7 @@ namespace Avalonia.Skia.RenderTests
     {
         private readonly IRenderTarget _renderTarget;
         public Size ClientSize { get; private set; }
-        internal IRenderer Renderer { get; private set; }
+        internal IRenderer Renderer { get; private set; } = null!;
         IRenderer IRenderRoot.Renderer => Renderer;
         IHitTester IRenderRoot.HitTester => new NullHitTester();
         public double RenderScaling { get; }
@@ -25,9 +25,9 @@ namespace Avalonia.Skia.RenderTests
         
         class NullHitTester : IHitTester
         {
-            public IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool> filter) => Array.Empty<Visual>();
+            public IEnumerable<Visual> HitTest(Point p, Visual root, Func<Visual, bool>? filter) => Array.Empty<Visual>();
 
-            public Visual HitTestFirst(Point p, Visual root, Func<Visual, bool> filter) => null;
+            public Visual? HitTestFirst(Point p, Visual root, Func<Visual, bool>? filter) => null;
         }
 
         internal void Initialize(IRenderer renderer, Control child)

tests/Avalonia.Skia.RenderTests/Avalonia.Skia.RenderTests.csproj

@@ -36,4 +36,5 @@
   <Import Project="..\..\build\ImageSharp.props" />
   <Import Project="..\..\build\SkiaSharp.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
 </Project>

tests/Avalonia.Skia.UnitTests/Avalonia.Skia.UnitTests.csproj

@@ -8,6 +8,7 @@
   <Import Project="..\..\build\Rx.props" />
   <Import Project="..\..\build\Microsoft.Reactive.Testing.props" />
   <Import Project="..\..\build\SharedVersion.props" />
+  <Import Project="..\..\build\NullableEnable.props" />
   <ItemGroup>
     <EmbeddedResource Include="..\Avalonia.RenderTests\Assets\**\*.ttf" LinkBase="Assets" />
     <None Remove="Fonts\**\*.ttf" />

tests/Avalonia.Skia.UnitTests/Media/FontManagerTests.cs

@@ -143,7 +143,7 @@ namespace Avalonia.Skia.UnitTests.Media
                     var result = FontManager.Current.TryGetGlyphTypeface(Typeface.Default, out var glyphTypeface);
 
                     Assert.True(result);
-
+                    Assert.NotNull(glyphTypeface);
                     Assert.Equal("Noto Mono", glyphTypeface.FamilyName);
                 }
             }
@@ -226,7 +226,7 @@ namespace Avalonia.Skia.UnitTests.Media
         [Theory]
         [InlineData("NotFound, Unknown", null)] // system fonts
         [InlineData("/#NotFound, /#Unknown", "avares://some/path")] // embedded fonts
-        public void Should_Match_Character_With_Fallbacks(string familyName, string baseUri)
+        public void Should_Match_Character_With_Fallbacks(string familyName, string? baseUri)
         {
             using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface.With(fontManagerImpl: new FontManagerImpl())))
             {
@@ -379,7 +379,7 @@ namespace Avalonia.Skia.UnitTests.Media
                     var result = FontManager.Current.TryGetGlyphTypeface(new Typeface("Abc, Segoe UI"), out var glyphTypeface);
 
                     Assert.True(result);
-
+                    Assert.NotNull(glyphTypeface);
                     Assert.Equal("Inter", glyphTypeface.FamilyName);
                 }
             }

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/MultiBufferTextSource.cs

@@ -16,7 +16,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
         public static TextRange TextRange => new TextRange(0, 50);
 
-        public TextRun GetTextRun(int textSourceIndex)
+        public TextRun? GetTextRun(int textSourceIndex)
         {
             if (textSourceIndex >= 50)
             {

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/SingleBufferTextSource.cs

@@ -16,7 +16,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
             _addEndOfParagraph = addEndOfParagraph;
         }
 
-        public TextRun GetTextRun(int textSourceIndex)
+        public TextRun? GetTextRun(int textSourceIndex)
         {
             if (textSourceIndex >= _text.Length)
             {

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextLayoutTests.cs

@@ -67,6 +67,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal("1 ", actual);
 
+                Assert.NotNull(textRun.Properties);
                 Assert.Equal(foreground, textRun.Properties.ForegroundBrush);
             }
         }
@@ -236,6 +237,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal("01", actual);
 
+                Assert.NotNull(textRun.Properties);
                 Assert.Equal(foreground, textRun.Properties.ForegroundBrush);
             }
         }
@@ -272,6 +274,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal("89", actual);
 
+                Assert.NotNull(textRun.Properties);
                 Assert.Equal(foreground, textRun.Properties.ForegroundBrush);
             }
         }
@@ -304,6 +307,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal(1, textRun.Length);
 
+                Assert.NotNull(textRun.Properties);
                 Assert.Equal(foreground, textRun.Properties.ForegroundBrush);
             }
         }
@@ -342,6 +346,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 Assert.Equal("😄", actual);
 
+                Assert.NotNull(textRun.Properties);
                 Assert.Equal(foreground, textRun.Properties.ForegroundBrush);
             }
         }
@@ -435,9 +440,9 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                     maxHeight: 125,
                     textStyleOverrides: spans);
 
-                Assert.Equal(foreground, layout.TextLines[0].TextRuns[1].Properties.ForegroundBrush);
+                Assert.Equal(foreground, layout.TextLines[0].TextRuns[1].Properties?.ForegroundBrush);
-                Assert.Equal(foreground, layout.TextLines[1].TextRuns[0].Properties.ForegroundBrush);
+                Assert.Equal(foreground, layout.TextLines[1].TextRuns[0].Properties?.ForegroundBrush);
-                Assert.Equal(foreground, layout.TextLines[2].TextRuns[0].Properties.ForegroundBrush);
+                Assert.Equal(foreground, layout.TextLines[2].TextRuns[0].Properties?.ForegroundBrush);
             }
         }
 
@@ -865,7 +870,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                     Brushes.Black,
                     flowDirection: FlowDirection.RightToLeft);
 
-                var firstRun = layout.TextLines[0].TextRuns[0] as ShapedTextRun;
+                var firstRun = Assert.IsType<ShapedTextRun>(layout.TextLines[0].TextRuns[0]);
 
                 var hit = layout.HitTestPoint(new Point());
 
@@ -891,7 +896,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                     currentX += advance;
                 }
 
-                var secondRun = layout.TextLines[0].TextRuns[1] as ShapedTextRun;
+                var secondRun = Assert.IsType<ShapedTextRun>(layout.TextLines[0].TextRuns[1]);
 
                 hit = layout.HitTestPoint(new Point(firstRun.Size.Width, 0));
 

tests/Avalonia.Skia.UnitTests/Media/TextFormatting/TextShaperTests.cs

@@ -52,6 +52,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 var splitResult = buffer.Split(1);
 
+                Assert.NotNull(splitResult.First);
                 Assert.Equal(1, splitResult.First.Length);
 
                 buffer = splitResult.Second;
@@ -61,6 +62,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
                 //\"๊  
                 splitResult = buffer.Split(1);
 
+                Assert.NotNull(splitResult.First);
                 Assert.Equal(2, splitResult.First.Length);
 
                 buffer = splitResult.Second;
@@ -86,6 +88,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 var first = splitResult.First;
 
+                Assert.NotNull(first);
                 Assert.Equal(6, first.Length);
             }
         }
@@ -101,6 +104,7 @@ namespace Avalonia.Skia.UnitTests.Media.TextFormatting
 
                 var splitResult = buffer.Split(0);
 
+                Assert.NotNull(splitResult.First);
                 Assert.Equal(0, splitResult.First.Length);
 
                 Assert.NotNull(splitResult.Second);

tests/TestFiles/BuildTasks/PInvoke/PInvoke.csproj

@@ -23,4 +23,5 @@
   <Import Project="..\..\..\..\build\ReferenceCoreLibraries.props" />
   <Import Project="..\..\..\..\build\BuildTargets.targets" />
   <Import Project="..\..\..\..\build\SourceGenerators.props" />
+  <Import Project="..\..\..\..\build\NullableEnable.props" />
 </Project>