fix(fonts): Adjust font loading for ms-appx resources from assemblies

- Font loading now uses common ms-appx path building properly to allow for arbitrary font loading.
- Enables dynamic inclusion of font files on apple targets

src/SourceGenerators/SourceGeneratorHelpers/Helpers/Nullable.cs

@@ -8,7 +8,7 @@
 
 namespace System.Diagnostics.CodeAnalysis
 {
-#if NETSTANDARD2_0 || NETCOREAPP2_0 || NETCOREAPP2_1 || NETCOREAPP2_2 || NET45 || NET451 || NET452 || NET46 || NET461 || NET462 || NET47 || NET471 || NET472 || NET48 || (!NET6_0_OR_GREATER && (__IOS__ || __ANDROID__ || __MACOS__))
+#if NETSTANDARD2_0 || NETCOREAPP2_0 || NETCOREAPP2_1 || NETCOREAPP2_2 || NET45 || NET451 || NET452 || NET46 || NET461 || NET462 || NET47 || NET471 || NET472 || NET48
 	/// <summary>Specifies that null is allowed as an input even if the corresponding type disallows it.</summary>
 	[AttributeUsage(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property, Inherited = false)]
 #if SYSTEM_PRIVATE_CORELIB

src/Uno.Foundation/Uno.Core.Extensions/Uno.Core.Extensions/StringExtensions.cs

@@ -21,6 +21,7 @@
 using System.Globalization;
 using System.Text;
 using System.Text.RegularExpressions;
+using System.Diagnostics.CodeAnalysis;
 
 #endregion
 
@@ -87,22 +88,23 @@ public static LineSplitEnumerator SplitLines(this ReadOnlySpan<char> instance)
 			return new LineSplitEnumerator(instance);
 		}
 
-		public static bool IsNullOrEmpty(this string instance)
+
+		public static bool IsNullOrEmpty([NotNullWhen(false)] this string instance)
 		{
 			return string.IsNullOrEmpty(instance);
 		}
-
-		public static bool IsNullOrWhiteSpace(this string instance)
+		
+		public static bool IsNullOrWhiteSpace([NotNullWhen(false)] this string instance)
 		{
 			return string.IsNullOrWhiteSpace(instance);
 		}
 
-		public static bool HasValue(this string instance)
+		public static bool HasValue([NotNullWhen(true)] this string instance)
 		{
 			return !string.IsNullOrWhiteSpace(instance);
 		}
 
-		public static bool HasValueTrimmed(this string instance)
+		public static bool HasValueTrimmed([NotNullWhen(true)] this string instance)
 		{
 			return !string.IsNullOrWhiteSpace(instance);
 		}

src/Uno.Foundation/Uno.Foundation.Reference.csproj

@@ -41,6 +41,10 @@
 		</EmbeddedResource>
 	</ItemGroup>
 
+	<ItemGroup>
+		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Extensions\Nullable.cs" />
+	</ItemGroup>
+
 	<ItemGroup>
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" Visible="False" />
 	</ItemGroup>

src/Uno.Foundation/Uno.Foundation.Skia.csproj

@@ -31,6 +31,10 @@
 		<ProjectReference Include="..\Uno.Foundation.Logging\Uno.Foundation.Logging.csproj" />
 	</ItemGroup>
 
+	<ItemGroup>
+		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Extensions\Nullable.cs" />
+	</ItemGroup>
+
 	<Import Project="..\Uno.CrossTargetting.props" />
 	<Import Project="Uno.Core.Extensions\Uno.Core.Extensions.props" />
 

src/Uno.Foundation/Uno.Foundation.csproj

@@ -38,6 +38,10 @@
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" Visible="False" />
 	</ItemGroup>
 
+	<ItemGroup>
+	  <Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Extensions\Nullable.cs" />
+	</ItemGroup>
+
 	<Import Project="..\Uno.CrossTargetting.props" />
 	<Import Project="Uno.Core.Extensions\Uno.Core.Extensions.props" />
 </Project>

src/Uno.UI.RemoteControl/Uno.UI.RemoteControl.Reference.csproj

@@ -33,10 +33,6 @@
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" />
 	</ItemGroup>
 
-	<ItemGroup>
-		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Helpers\Nullable.cs" />
-	</ItemGroup>
-
 	<ItemGroup>
 	  <Content Include="buildTransitive\Uno.UI.RemoteControl.targets">
 	    <PackagePath>build</PackagePath>

src/Uno.UI.RemoteControl/Uno.UI.RemoteControl.Skia.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk" ToolsVersion="15.0">
 
 	<PropertyGroup>
-		<TargetFrameworks>netstandard2.0;net5.0</TargetFrameworks>
+		<TargetFrameworks>netstandard2.0</TargetFrameworks>
 	</PropertyGroup>
 
 	<PropertyGroup Condition="'$(MSBuildRuntimeType)'=='Core' or '$(IsRunningInsideVisualStudio)'=='true'">
@@ -36,10 +36,6 @@
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" />
 	</ItemGroup>
 
-	<ItemGroup>
-		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Helpers\Nullable.cs" />
-	</ItemGroup>
-
 	<ItemGroup>
 		<EmbeddedResource Include="LinkerDefinition.Wasm.xml">
 			<LogicalName>$(AssemblyName).xml</LogicalName>

src/Uno.UI.RemoteControl/Uno.UI.RemoteControl.csproj

@@ -27,10 +27,6 @@
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" />
 	</ItemGroup>
 
-	<ItemGroup>
-		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Helpers\Nullable.cs" />
-	</ItemGroup>
-
 	<ItemGroup Condition="'$(TargetFramework)'!='netstandard2.0'">
 		<EmbeddedResource Include="LinkerDefinition.Xamarin.xml">
 			<LogicalName>$(AssemblyName).xml</LogicalName>

src/Uno.UI.RemoteControl/Uno.UI.RemoteControl.netcoremobile.csproj

@@ -34,10 +34,6 @@
 		<UpToDateCheckInput Include="**\*.cs" Exclude="bin\**\*.cs;obj\**\*.cs;" />
 	</ItemGroup>
 
-	<ItemGroup>
-		<Compile Include="..\SourceGenerators\SourceGeneratorHelpers\Helpers\Nullable.cs" Link="Helpers\Nullable.cs" />
-	</ItemGroup>
-
 	<ItemGroup Condition="'$(TargetFramework)'!='netstandard2.0'">
 		<EmbeddedResource Include="LinkerDefinition.Xamarin.xml">
 			<LogicalName>$(AssemblyName).xml</LogicalName>

src/Uno.UI.RuntimeTests/Tests/Windows_UI_Xaml_Controls/Given_TextBlock.cs

@@ -109,5 +109,35 @@ public void When_Inlines_XamlRoot()
 				Assert.AreEqual(SUT.XamlRoot, inline.XamlRoot);
 			}
 		}
+
+		[TestMethod]
+		[RunsOnUIThread]
+		public async Task When_FontFamily_In_Separate_Assembly()
+		{
+			var SUT = new TextBlock { Text = "\xE102\xE102\xE102\xE102\xE102" };
+			WindowHelper.WindowContent = SUT;
+			await WindowHelper.WaitForIdle();
+
+			var size = new Size(1000, 1000);
+			SUT.Measure(size);
+
+			var originalSize = SUT.DesiredSize;
+
+			Assert.AreNotEqual(0, SUT.DesiredSize.Width);
+			Assert.AreNotEqual(0, SUT.DesiredSize.Height);
+
+			SUT.FontFamily = new Windows.UI.Xaml.Media.FontFamily("ms-appx://Uno.UI.RuntimeTests/Assets/Fonts/uno-fluentui-assets-v2.ttf");
+
+			int counter = 3;
+
+			do
+			{
+				await WindowHelper.WaitForIdle();
+				await Task.Delay(100);
+			}
+			while (SUT.DesiredSize == originalSize && counter-- > 0);
+
+			Assert.AreNotEqual(originalSize, SUT.DesiredSize);
+		}
 	}
 }

src/Uno.UI.RuntimeTests/Uno.UI.RuntimeTests.Wasm.csproj

@@ -101,4 +101,8 @@
 
 		<UpToDateCheckInput Include="$(PlatformItemsBasePath)**\*.xaml" Exclude="$(PlatformItemsBasePath)bin\**\*.xaml;$(PlatformItemsBasePath)obj\**\*.xaml" />
 	</ItemGroup>
+
+	<ItemGroup>
+	  <None Remove="Assets\Fonts\uno-fluentui-assets-v2.ttf" />
+	</ItemGroup>
 </Project>

src/Uno.UI/Controls/NSFontHelper.macOS.cs

@@ -199,32 +199,64 @@ private static NSFont ApplyStyle(NSFont font, nfloat size, FontStyle fontStyle)
 		private static NSFont? GetFontFromFile(nfloat size, string file)
 		{
 			var fileName = Path.GetFileNameWithoutExtension(file);
-			var fileExtension = Path.GetExtension(file)?.Replace(".", "") ?? "";
-
-			var url = NSBundle
-				.MainBundle
-				.GetUrlForResource(
-					name: fileName,
-					fileExtension: fileExtension,
-					subdirectory: "Fonts"
-				);
-
-			if (url == null)
+			var fileExtension = Path.GetExtension(file)!.Substring(1);
+
+			var url = file.Contains("/")
+
+				// Search the file using the appropriate subdirectory
+				? NSBundle
+					.MainBundle
+					.GetUrlForResource(
+						name: fileName,
+						fileExtension: fileExtension,
+						subdirectory: Path.GetDirectoryName(file))
+
+				// Legacy behavior when fonts were located in the fonts folder.
+				: NSBundle
+					.MainBundle
+					.GetUrlForResource(
+						name: fileName,
+						fileExtension: fileExtension,
+						subdirectory: "Fonts");
+
+			if (url is null)
 			{
+				if (typeof(NSFontHelper).Log().IsEnabled(LogLevel.Debug))
+				{
+					typeof(NSFontHelper).Log().Debug($"Unable to find font in bundle using {file}");
+				}
+
 				return null;
 			}
 
 			var fontData = NSData.FromUrl(url);
-			if (fontData == null)
+			if (fontData is null)
 			{
+				if (typeof(NSFontHelper).Log().IsEnabled(LogLevel.Debug))
+				{
+					typeof(NSFontHelper).Log().Debug($"Unable to load font in bundle using {url}");
+				}
+
 				return null;
 			}
 
 			//iOS loads NSFonts based on the PostScriptName of the font file
 			using var fontProvider = new CGDataProvider(fontData);
-			using var font = CGFont.CreateFromProvider(fontProvider);
+			var font = CGFont.CreateFromProvider(fontProvider);
 
-			return font != null ? NSFont.FromFontName(font.PostScriptName, size) : null;
+			if (font is not null && CoreText.CTFontManager.RegisterGraphicsFont(font, out var error))
+			{
+				return NSFont.FromFontName(font.PostScriptName, size);
+			}
+			else
+			{
+				if (typeof(NSFontHelper).Log().IsEnabled(LogLevel.Debug))
+				{
+					typeof(NSFontHelper).Log().Debug($"Unable to register font from {file}");
+				}
+
+				return null;
+			}
 		}
 		#endregion