perf: Enable LINQ-related performance analyzers

.editorconfig

@@ -238,6 +238,11 @@ dotnet_diagnostic.RS0030.severity = error
 dotnet_analyzer_diagnostic.category-Performance.severity = none #error - Uncomment when all violations are fixed.
 
 dotnet_diagnostic.CA1805.severity = error
+dotnet_diagnostic.CA1826.severity = error
+dotnet_diagnostic.CA1827.severity = error
+dotnet_diagnostic.CA1828.severity = error
+dotnet_diagnostic.CA1829.severity = error
+
 dotnet_diagnostic.CA1061.severity = none
 dotnet_diagnostic.CA1802.severity = none
 dotnet_diagnostic.CA1014.severity = none
@@ -290,7 +295,6 @@ dotnet_diagnostic.CA1508.severity = none
 dotnet_diagnostic.CA2008.severity = none
 dotnet_diagnostic.CA1810.severity = none
 dotnet_diagnostic.CA1309.severity = none
-dotnet_diagnostic.CA1829.severity = none
 dotnet_diagnostic.CA3075.severity = none
 dotnet_diagnostic.CA1815.severity = none
 dotnet_diagnostic.CA1819.severity = none
@@ -302,7 +306,6 @@ dotnet_diagnostic.CA2214.severity = none
 dotnet_diagnostic.CA1033.severity = none
 dotnet_diagnostic.CA2213.severity = none
 dotnet_diagnostic.CA1068.severity = none
-dotnet_diagnostic.CA1826.severity = none
 dotnet_diagnostic.CA2016.severity = none
 dotnet_diagnostic.CA1835.severity = none
 dotnet_diagnostic.CA1069.severity = none

src/SamplesApp/.editorconfig

@@ -1,3 +1,4 @@
 [*.cs]
 dotnet_analyzer_diagnostic.category-Performance.severity = none
-dotnet_diagnostic.CA1805.severity = none
+dotnet_diagnostic.CA1805.severity = none
+dotnet_diagnostic.CA1036.severity = none

src/SamplesApp/SamplesApp.UnitTests.Shared/Controls/UITests/Presentation/SampleChooserViewModel.cs

@@ -329,7 +329,7 @@ from sample in category.SamplesContent
 
 				if (_log.IsEnabled(LogLevel.Debug))
 				{
-					_log.Debug($"Generating tests for {tests.Count()} test in {folderName}");
+					_log.Debug($"Generating tests for {tests.Length} test in {folderName}");
 				}
 
 				var target = new Windows.UI.Xaml.Media.Imaging.RenderTargetBitmap();

src/SamplesApp/UITests.Shared/Windows_UI_Xaml_Controls/ListView/IndexAwareItemContainerStyleSelector.cs

@@ -24,7 +24,7 @@ protected override Style SelectStyleCore(object item, DependencyObject container
 				return FirstItemStyle;
 			}
 
-			var itemsCount = itemsControl.Items?.Count() ?? (itemsControl.ItemsSource as IEnumerable)?.Cast<object>().Count() ?? 0;
+			var itemsCount = itemsControl.Items?.Count ?? (itemsControl.ItemsSource as IEnumerable)?.Cast<object>().Count() ?? 0;
 			if (index == itemsCount - 1)
 			{
 				return LastItemStyle;

src/SourceGenerators/System.Xaml.Tests/Test/System.Xaml/XamlSchemaContextTest.cs

@@ -165,7 +165,7 @@ public void TryGetCompatibleXamlNamespace ()
 		public void GetXamlTypeAndAllXamlTypes ()
 		{
 			var ctx = new XamlSchemaContext (new Assembly [] {typeof (string).Assembly}); // build with corlib.
-			Assert.AreEqual (0, ctx.GetAllXamlTypes (XamlLanguage.Xaml2006Namespace).Count (), "#0"); // premise
+			Assert.AreEqual (0, ctx.GetAllXamlTypes (XamlLanguage.Xaml2006Namespace).Count, "#0"); // premise
 
 			var xt = ctx.GetXamlType (typeof (string));
 			Assert.IsNotNull (xt, "#1");
@@ -176,7 +176,7 @@ public void GetXamlTypeAndAllXamlTypes ()
 			Assert.IsTrue (object.ReferenceEquals (ctx.GetXamlType (GetType ()), ctx.GetXamlType (GetType ())), "#4");
 
 			// after getting these types, it still returns 0. So it's not all about caching.
-			Assert.AreEqual (0, ctx.GetAllXamlTypes (XamlLanguage.Xaml2006Namespace).Count (), "#5");
+			Assert.AreEqual (0, ctx.GetAllXamlTypes (XamlLanguage.Xaml2006Namespace).Count, "#5");
 		}
 
 		[Test]
@@ -197,7 +197,7 @@ public void GetAllXamlTypesInXaml2006Namespace ()
 			// There are some special types that have non-default name: MemberDefinition, PropertyDefinition
 
 			var l = ctx.GetAllXamlTypes (XamlLanguage.Xaml2006Namespace);
-			Assert.IsTrue (l.Count () > 40, "#1");
+			Assert.IsTrue (l.Count > 40, "#1");
 			Assert.IsTrue (l.Any (t => t.UnderlyingType == typeof (MemberDefinition)), "#2");
 			Assert.IsTrue (l.Any (t => t.Name == "AmbientAttribute"), "#3");
 			Assert.IsTrue (l.Any (t => t.Name == "XData"), "#4");

src/SourceGenerators/Uno.UI.SourceGenerators/Telemetry/PersistenceChannel/StorageService.cs

@@ -319,7 +319,7 @@ private void CalculateSize()
 		{
 			string[] storageFiles = Directory.GetFiles(StorageFolder, "*.*");
 
-			_storageCountFiles = storageFiles.Count();
+			_storageCountFiles = storageFiles.Length;
 
 			long storageSizeInBytes = 0;
 			foreach (string file in storageFiles)

src/SourceGenerators/Uno.UI.SourceGenerators/XamlGenerator/XamlCodeGeneration.cs

@@ -647,7 +647,7 @@ private string[] GetResourceKeys(CancellationToken ct)
 			}
 
 #if DEBUG
-			Console.Write(resourceKeys.Count() + " localization keys found");
+			Console.Write(resourceKeys.Length + " localization keys found");
 #endif
 			return resourceKeys;
 		}

src/SourceGenerators/Uno.UI.SourceGenerators/XamlGenerator/XamlFileGenerator.cs

@@ -3263,7 +3263,7 @@ private void BuildExtendedProperties(IIndentedStringBuilder outerwriter, XamlObj
 										closureName
 									);
 
-									if (member.Objects.Count() == 1)
+									if (member.Objects.Count == 1)
 									{
 										BuildChild(writer, member, member.Objects.First());
 									}
@@ -6217,7 +6217,7 @@ private string GenerateConstructorParameters(XamlType xamlType)
 				if (type != null)
 				{
 					var q = from m in type.Constructors
-							where m.Parameters.Count() == 1
+							where m.Parameters.Length == 1
 							where SymbolEqualityComparer.Default.Equals(m.Parameters.First().Type, _androidContentContextSymbol)
 							select m;
 

src/Uno.Foundation/UriExtensions.cs

@@ -21,7 +21,7 @@ public static IDictionary<string, string> GetParameters(this Uri uri)
 				.OriginalString
 				.Split(new[] { '?', '&' }, StringSplitOptions.RemoveEmptyEntries)
 				.Select(p => p.Split(new[] { '=' }))
-				.Where(parts => parts.Count() > 1)
+				.Where(parts => parts.Length > 1)
 				.ToDictionary(parts => parts[0], parts => String.Join("=", parts.Skip(1)));
 		}
 

src/Uno.UI.RuntimeTests/IntegrationTests/dxaml/controls/calendarview/CalendarViewIntegrationTests.cs

@@ -2556,7 +2556,7 @@ await RunOnUIThread(() =>
 					});
 
 
-					for (var i = 0; i < testData.snapPoints.Count(); i++)
+					for (var i = 0; i < testData.snapPoints.Length; i++)
 					{
 						LOG_OUTPUT("scroll down to next snap point and wait for viewchanged event.");
 						TestServices.InputHelper.ScrollMouseWheel(cv, -1);

src/Uno.UI.RuntimeTests/MUX/Microsoft_UI_Xaml_Controls/Breadcrumb/BreadcrumbTests.cs

@@ -307,7 +307,8 @@ await RunOnUIThread.ExecuteAsync(() =>
 
 					await RunOnUIThread.ExecuteAsync(() =>
 					{
-						var flyout = VisualTreeHelper.GetOpenPopups(Window.Current).Last();
+						var openPopups = VisualTreeHelper.GetOpenPopups(Window.Current);
+						var flyout = openPopups[openPopups.Count - 1];
 						Verify.IsNotNull(flyout, "Flyout could not be retrieved");
 						var ellipsisItemsRepeater = TestUtilities.FindDescendents<ItemsRepeater>(flyout).Single();
 						Verify.IsNotNull(ellipsisItemsRepeater, "The underlying flyout items repeater (1) could not be retrieved");
@@ -388,7 +389,8 @@ await RunOnUIThread.ExecuteAsync(() =>
 
 					await RunOnUIThread.ExecuteAsync(() =>
 					{
-						var flyout = VisualTreeHelper.GetOpenPopups(Window.Current).Last();
+						var openPopups = VisualTreeHelper.GetOpenPopups(Window.Current);
+						var flyout = openPopups[openPopups.Count - 1];
 						Verify.IsNotNull(flyout, "Flyout could not be retrieved");
 						var ellipsisItemsRepeater = TestUtilities.FindDescendents<ItemsRepeater>(flyout).Single();
 						Verify.IsNotNull(ellipsisItemsRepeater, "The underlying flyout items repeater (1) could not be retrieved");

src/Uno.UI.RuntimeTests/MUX/Microsoft_UI_Xaml_Controls/Repeater/SelectionModelTests.cs

@@ -1375,9 +1375,9 @@ private void ValidateSelection(
 					Verify.AreEqual(selectionModel.SelectedItem, GetData(selectionModel, expectedSelected[0]));
 				}
 
-				int itemsCount = selectionModel.SelectedItems.Count();
+				int itemsCount = selectionModel.SelectedItems.Count;
 				Verify.AreEqual(selectionModel.Source != null ? expectedSelected.Count - selectedInnerNodes : 0, itemsCount);
-				int indicesCount = selectionModel.SelectedIndices.Count();
+				int indicesCount = selectionModel.SelectedIndices.Count;
 				Verify.AreEqual(expectedSelected.Count - selectedInnerNodes, indicesCount);
 			}
 

src/Uno.UI.RuntimeTests/Tests/Windows_Globalization/Given_ApplicationLanguages.cs

@@ -20,7 +20,7 @@ public void Test_Chinese_With_Script_Subtag()
 		{
 			ApplicationLanguages.PrimaryLanguageOverride = "zh-Hans-CN";
 
-			ApplicationLanguages.Languages.First().Should().Be("zh-Hans-CN");
+			ApplicationLanguages.Languages[0].Should().Be("zh-Hans-CN");
 			CultureInfo.CurrentCulture.Name.Should().BeOneOf("zh-CN", "zh-Hans-CN");
 			CultureInfo.CurrentUICulture.Name.Should().BeOneOf("zh-CN", "zh-Hans-CN");
 		}
@@ -30,7 +30,7 @@ public void Test_French_With_Script_Subtag()
 		{
 			ApplicationLanguages.PrimaryLanguageOverride = "fr-Latn-CA";
 
-			ApplicationLanguages.Languages.First().Should().Be("fr-Latn-CA");
+			ApplicationLanguages.Languages[0].Should().Be("fr-Latn-CA");
 			CultureInfo.CurrentCulture.Name.Should().BeOneOf("fr-CA", "fr-Latn-CA");
 			CultureInfo.CurrentUICulture.Name.Should().BeOneOf("fr-CA", "fr-Latn-CA");
 		}

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Documents/Given_Run.cs

@@ -140,12 +140,12 @@ private static void AssertSegmentsMatch(ExpectedSegment[] expectedSegments, IRea
 				if (expected.LineBreakLength == 2)
 				{
 					Assert.AreEqual(expected.Text.Length - 1, result.Glyphs.Count);
-					Assert.AreEqual(start + expected.Text.Length - 2, result.Glyphs.Last().Cluster);
+					Assert.AreEqual(start + expected.Text.Length - 2, result.Glyphs[result.Glyphs.Count - 1].Cluster);
 				}
 				else
 				{
 					Assert.AreEqual(expected.Text.Length, result.Glyphs.Count);
-					Assert.AreEqual(start + expected.Text.Length - 1, result.Glyphs.Last().Cluster);
+					Assert.AreEqual(start + expected.Text.Length - 1, result.Glyphs[result.Glyphs.Count - 1].Cluster);
 				}
 
 				Assert.AreEqual(start, result.Glyphs[0].Cluster);

src/Uno.UI.TestComparer/AppCenterTestsDownloader.cs

@@ -53,7 +53,7 @@ public async Task Download(string testCloudApiKey, string basePath, int runLimit
 
                 foreach (var run in validRuns.Select((v, i) => new { Index = i, Value = v }))
                 {
-                    Console.WriteLine($"Getting run {run.Index + 1} of {validRuns.Count()} for {run.Value.Platform} at {run.Value.Date}...");
+                    Console.WriteLine($"Getting run {run.Index + 1} of {validRuns.Length} for {run.Value.Platform} at {run.Value.Date}...");
 
                     var runName = $"{run.Value.Date:yyyyMMdd-hhmmss}-{run.Value.Id}";
                     var fullPath = Path.Combine(basePath, run.Value.Platform, runName);

src/Uno.UI.Tests/Windows_Data_Xml/DomTests/Given_XmlDocument.cs

@@ -32,8 +32,8 @@ public void When_Enumerate_ChildNodes()
 			{
 				Assert.IsInstanceOfType(childNode, typeof(XmlElement));				
 			}
-			Assert.AreEqual("title", childNodes.First().NodeName);
-			Assert.AreEqual("para", childNodes.Last().NodeName);
+			Assert.AreEqual("title", childNodes[0].NodeName);
+			Assert.AreEqual("para", childNodes[(int)childNodes.Length - 1].NodeName);
 		}
 
 		[TestMethod]

src/Uno.UI.Tests/Windows_Globalization/Given_CalendarFormatter.cs

@@ -21,7 +21,7 @@ public void When_UsingVariousLanguages(string format, string language, string ex
 		{
 			var sut = new DateTimeFormatter(format, new[] {language});
 
-			var firstPattern = sut.Patterns.First();
+			var firstPattern = sut.Patterns[0];
 
 			using var _ = new AssertionScope();
 

src/Uno.UI/Controls/NativeFramePresenter.iOS.cs

@@ -325,7 +325,7 @@ bool CorrelatesNavigatingRequest()
 							if (newItem != null
 								&& e.NewStartingIndex == (collection.Count - 1)
 								&& (frameRequest.NavigationMode == NavigationMode.New || frameRequest.NavigationMode == NavigationMode.Forward)
-								&& newItem.SourcePageType == frameRequest.BackStackPageTypes.LastOrDefault())
+								&& newItem.SourcePageType == (frameRequest.BackStackPageTypes.Count == 0 ? null : frameRequest.BackStackPageTypes[frameRequest.BackStackPageTypes.Count - 1]))
 							{
 								return true;
 							}

src/Uno.UI/Controls/UIFontHelper.iOS.cs

@@ -201,7 +201,7 @@ private static UIFont GetFontFromFamilyName(nfloat size, string familyName)
 		{
 			//If only one font exists for this family name, use it. Otherwise we will need to inspect the file for the right font name
 			var fontNames = UIFont.FontNamesForFamilyName(familyName);
-			return fontNames.Count() == 1 ? UIFont.FromName(fontNames[0], size) : null;
+			return fontNames.Length == 1 ? UIFont.FromName(fontNames[0], size) : null;
 		}
 
 		private static UIFont GetFontFromFile(nfloat size, string file)

src/Uno.UI/DirectUI/TrackableDateCollection.cs

@@ -162,7 +162,7 @@ internal void CountOf(DateTime value, out uint pCount)
 			uint count = 0;
 			pCount = 0;
 
-			for (uint i = 0; i < m_vector.Count(); ++i)
+			for (uint i = 0; i < m_vector.Count; ++i)
 			{
 				if (m_areEquivalentComparer(m_vector[(int)i], value))
 				{
@@ -177,7 +177,7 @@ internal void CountOf(DateTime value, out uint pCount)
 		internal void RemoveAll(DateTime value, uint? pFromHint = null)
 		{
 			int from = (int)(pFromHint.HasValue ? pFromHint : 0);
-			int i = (int)(m_vector.Count()) - 1;
+			int i = (int)(m_vector.Count) - 1;
 
 			for (; i >= from; --i)
 			{

src/Uno.UI/Helpers/NativeFramePresenterUIGestureRecognizerDelegate.cs

@@ -14,7 +14,7 @@ public NativeFramePresenterUIGestureRecognizerDelegate(Func<UINavigationControll
 		}
 		public override bool ShouldBegin(UIGestureRecognizer recognizer)
 		{
-			return _navigationController()?.ViewControllers?.Count() > 1;
+			return _navigationController()?.ViewControllers?.Length > 1;
 		}
 	}
 }

src/Uno.UI/UI/Xaml/Controls/ItemCollection.cs

@@ -119,7 +119,7 @@ public bool Remove(object item)
 			}
 		}
 
-		public int Count => _itemsSource == null ? _inner.Count : _itemsSource.Count();
+		public int Count => _itemsSource == null ? _inner.Count : _itemsSource.Count;
 
 		public uint Size => (uint)Count;
 

src/Uno.UI/UI/Xaml/Controls/Pivot/NativePivotPresenter.Android.cs

@@ -85,7 +85,7 @@ partial void UpdateItems()
 			_adapter?.NotifyDataSetChanged();
 			if (_pager != null)
 			{
-				_pager.OffscreenPageLimit = Items.Count();
+				_pager.OffscreenPageLimit = Items.Count;
 			}
 			_tabStrip?.Update();
 		}

src/Uno.UI/UI/Xaml/Controls/Pivot/PivotAdapter.Android.cs

@@ -54,7 +54,7 @@ public override AndroidX.Fragment.App.Fragment GetItem(int position)
 
 		public override int Count
 		{
-			get { return _fragments.Count(); }
+			get { return _fragments.Count; }
 		}
 
 		public override Java.Lang.ICharSequence GetPageTitleFormatted(int position)

src/Uno.UI/UI/Xaml/Data/CollectionView.cs

@@ -152,7 +152,7 @@ public int Count
 
 					foreach (ICollectionViewGroup group in CollectionGroups)
 					{
-						count += group.GroupItems.Count();
+						count += group.GroupItems.Count;
 					}
 
 					return count;

src/Uno.UWP/Globalization/ApplicationLanguages.cs

@@ -80,7 +80,7 @@ private static void ApplyLanguages()
 				Languages = languages.Distinct().ToArray();
 			}
 
-			var primaryLanguage = Languages.FirstOrDefault();
+			var primaryLanguage = Languages.Count > 0 ? Languages[0] : null;
 
 			if(primaryLanguage is not null)
 			{

src/Uno.UWP/Networking/Connectivity/NetworkInformation.Android.cs

@@ -109,7 +109,7 @@ public static IReadOnlyList<HostName> GetHostNames()
 							string androCanonical = interfaceAddress.Address.CanonicalHostName;
 							// seems like == androCanonical
 							string androHostName = interfaceAddress.Address.HostName;
-							bool androIPv46 = (interfaceAddress.Address.GetAddress().Count() == 4);
+							bool androIPv46 = (interfaceAddress.Address.GetAddress().Length == 4);
 
 							// we have all required data from Android, and we can use them
 							HostName newHost = new HostName();

src/Uno.UWP/Storage/Pickers/FileOpenPicker.Android.cs

@@ -39,7 +39,7 @@ internal static bool TryHandleIntent(Intent intent, Result resultCode)
 		private async Task<StorageFile?> PickSingleFileTaskAsync(CancellationToken token)
 		{
 			var files = await PickFilesAsync(false, token);
-			return files.FirstOrDefault();
+			return files.Count == 0 ? null : files[0];
 		}
 
 		private async Task<IReadOnlyList<StorageFile>> PickMultipleFilesTaskAsync(CancellationToken token)

src/Uno.UWP/Storage/Pickers/FileOpenPicker.iOS.cs

@@ -18,7 +18,7 @@ public partial class FileOpenPicker
 		private async Task<StorageFile?> PickSingleFileTaskAsync(CancellationToken token)
 		{
 			var files = await PickFilesAsync(false, token);
-			return files.FirstOrDefault();
+			return files.Count == 0 ? null : files[0];
 		}
 
 		private async Task<IReadOnlyList<StorageFile>> PickMultipleFilesTaskAsync(CancellationToken token) =>

src/Uno.UWP/Storage/Pickers/FileOpenPicker.wasm.cs

@@ -35,7 +35,7 @@ internal static bool IsNativePickerSupported()
 		private async Task<StorageFile?> PickSingleFileTaskAsync(CancellationToken token)
 		{
 			var files = await PickFilesAsync(false, token);
-			return files.FirstOrDefault();
+			return files.Count > 0 ? files[0] : null;
 		}
 
 		private async Task<IReadOnlyList<StorageFile>> PickMultipleFilesTaskAsync(CancellationToken token)