Properly support relative Uris in StyleInclude/ResourceInclude

src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs

@@ -274,7 +274,7 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions
             {
                 var uriText = text.Trim();
 
-                var kind = ((!uriText?.StartsWith("/") == true) ? UriKind.Absolute : UriKind.Relative);
+                var kind = ((!uriText?.StartsWith("/") == true) ? UriKind.RelativeOrAbsolute : UriKind.Relative);
 
                 if (string.IsNullOrWhiteSpace(uriText) || !Uri.TryCreate(uriText, kind, out var _))
                 {

src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/GroupTransformers/XamlIncludeGroupTransformer.cs

@@ -36,34 +36,37 @@ internal class AvaloniaXamlIncludeTransformer : IXamlAstGroupTransformer
             return context.ParseError($"Source property must be set on the \"{nodeTypeName}\" node.", node);
         }
 
+        // We expect that AvaloniaXamlIlLanguageParseIntrinsics has already parsed the Uri and created node like: `new Uri(assetPath, uriKind)`.
         if (sourceProperty.Values.OfType<XamlAstNewClrObjectNode>().FirstOrDefault() is not { } sourceUriNode
             || sourceUriNode.Type.GetClrType() != context.GetAvaloniaTypes().Uri
-            || sourceUriNode.Arguments.FirstOrDefault() is not XamlConstantNode { Constant: string originalAssetPath })
+            || sourceUriNode.Arguments.FirstOrDefault() is not XamlConstantNode { Constant: string originalAssetPath }
+            || sourceUriNode.Arguments.Skip(1).FirstOrDefault() is not XamlConstantNode { Constant: int uriKind })
         {
             // TODO: make it a compiler warning
             // Source value can be set with markup extension instead of the Uri object node, we don't support it here yet.
             return node;
         }
 
-        if (originalAssetPath.StartsWith("/"))
+        var uriPath = new Uri(originalAssetPath, (UriKind)uriKind);
+        if (!uriPath.IsAbsoluteUri)
         {
             var baseUrl = context.CurrentDocument.Uri ?? throw new InvalidOperationException("CurrentDocument URI is null.");
-            originalAssetPath = baseUrl.Substring(0, baseUrl.LastIndexOf('/')) + originalAssetPath;
+            uriPath = new Uri(new Uri(baseUrl, UriKind.Absolute), uriPath);
         }
-        else if (!originalAssetPath.StartsWith("avares://"))
+        else if (!uriPath.Scheme.Equals("avares", StringComparison.CurrentCultureIgnoreCase))
         {
             return context.ParseError(
                 $"Avalonia supports only \"avares://\" sources or relative sources starting with \"/\" on the \"{nodeTypeName}\" node.",
                 node);
         }
 
-        originalAssetPath = Uri.UnescapeDataString(new Uri(originalAssetPath).AbsoluteUri);
+        var assetPathUri = Uri.UnescapeDataString(uriPath.AbsoluteUri);
-        var assetPath = originalAssetPath.Replace("avares://", "");
+        var assetPath = assetPathUri.Replace("avares://", "");
         var assemblyNameSeparator = assetPath.IndexOf('/');
         var assembly = assetPath.Substring(0, assemblyNameSeparator);
         var fullTypeName = Path.GetFileNameWithoutExtension(assetPath.Replace('/', '.'));
 
-        if (context.Documents.FirstOrDefault(d => string.Equals(d.Uri, originalAssetPath, StringComparison.InvariantCultureIgnoreCase)) is {} targetDocument)
+        if (context.Documents.FirstOrDefault(d => string.Equals(d.Uri, assetPathUri, StringComparison.InvariantCultureIgnoreCase)) is {} targetDocument)
         {
             if (targetDocument.ClassType is not null)
             {
@@ -72,7 +75,7 @@ internal class AvaloniaXamlIncludeTransformer : IXamlAstGroupTransformer
 
             if (targetDocument.BuildMethod is null)
             {
-                return context.ParseError($"\"{originalAssetPath}\" cannot be instantiated.", node);
+                return context.ParseError($"\"{assetPathUri}\" cannot be instantiated.", node);
             }
 
             return FromMethod(context, targetDocument.BuildMethod, node);
@@ -81,7 +84,7 @@ internal class AvaloniaXamlIncludeTransformer : IXamlAstGroupTransformer
 
         if (context.Configuration.TypeSystem.FindAssembly(assembly) is not { } assetAssembly)
         {
-            return context.ParseError($"Assembly \"{assembly}\" was not found from the \"{originalAssetPath}\" source.", node);
+            return context.ParseError($"Assembly \"{assembly}\" was not found from the \"{assetPathUri}\" source.", node);
         }
 
         if (assetAssembly.FindType(fullTypeName) is { } type

src/Markup/Avalonia.Markup.Xaml/Converters/AvaloniaUriTypeConverter.cs

@@ -17,7 +17,7 @@ namespace Avalonia.Markup.Xaml.Converters
             if (s == null)
                 return null;
             //On Unix Uri tries to interpret paths starting with "/" as file Uris
-            var kind = s.StartsWith("/") ? UriKind.Relative : UriKind.Absolute;
+            var kind = s.StartsWith("/") ? UriKind.Relative : UriKind.RelativeOrAbsolute;
             if (!Uri.TryCreate(s, kind, out var res))
                 throw new ArgumentException("Unable to parse URI: " + s);
             return res;

tests/Avalonia.Markup.Xaml.UnitTests/Xaml/StyleIncludeTests.cs

@@ -79,7 +79,35 @@ public class StyleIncludeTests
     }
     
     [Fact]
-    public void Relative_StyleInclude_Is_Resolved_With_Two_Files()
+    public void Relative_Back_StyleInclude_Is_Resolved_With_Two_Files()
+    {
+        var documents = new[]
+        {
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Subfolder/Style.xaml"), @"
+<Style xmlns='https://github.com/avaloniaui'
+       xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <Style.Resources>
+        <Color x:Key='Red'>Red</Color>
+    </Style.Resources>
+</Style>"),
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Subfolder/Folder/Root.xaml"), @"
+<ContentControl xmlns='https://github.com/avaloniaui'
+                xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <ContentControl.Resources>
+        <StyleInclude x:Key='Include' Source='../Style.xaml'/>
+    </ContentControl.Resources>
+</ContentControl>")
+        };
+        
+        var objects = AvaloniaRuntimeXamlLoader.LoadGroup(documents);
+        var style = Assert.IsType<Style>(objects[0]);
+        var contentControl = Assert.IsType<ContentControl>(objects[1]);
+
+        Assert.IsType<Style>(contentControl.Resources["Include"]);
+    }
+    
+    [Fact]
+    public void Relative_Root_StyleInclude_Is_Resolved_With_Two_Files()
     {
         var documents = new[]
         {
@@ -94,7 +122,63 @@ public class StyleIncludeTests
 <ContentControl xmlns='https://github.com/avaloniaui'
                 xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
     <ContentControl.Resources>
-        <StyleInclude x:Key='Include' Source='/../Style.xaml'/>
+        <StyleInclude x:Key='Include' Source='/Style.xaml'/>
+    </ContentControl.Resources>
+</ContentControl>")
+        };
+        
+        var objects = AvaloniaRuntimeXamlLoader.LoadGroup(documents);
+        var style = Assert.IsType<Style>(objects[0]);
+        var contentControl = Assert.IsType<ContentControl>(objects[1]);
+
+        Assert.IsType<Style>(contentControl.Resources["Include"]);
+    }
+    
+    [Fact]
+    public void Relative_StyleInclude_Is_Resolved_With_Two_Files()
+    {
+        var documents = new[]
+        {
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Folder/Style.xaml"), @"
+<Style xmlns='https://github.com/avaloniaui'
+       xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <Style.Resources>
+        <Color x:Key='Red'>Red</Color>
+    </Style.Resources>
+</Style>"),
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Folder/Root.xaml"), @"
+<ContentControl xmlns='https://github.com/avaloniaui'
+                xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <ContentControl.Resources>
+        <StyleInclude x:Key='Include' Source='Style.xaml'/>
+    </ContentControl.Resources>
+</ContentControl>")
+        };
+        
+        var objects = AvaloniaRuntimeXamlLoader.LoadGroup(documents);
+        var style = Assert.IsType<Style>(objects[0]);
+        var contentControl = Assert.IsType<ContentControl>(objects[1]);
+
+        Assert.IsType<Style>(contentControl.Resources["Include"]);
+    }
+    
+    [Fact]
+    public void Relative_Dot_Syntax__StyleInclude_Is_Resolved_With_Two_Files()
+    {
+        var documents = new[]
+        {
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Folder/Style.xaml"), @"
+<Style xmlns='https://github.com/avaloniaui'
+       xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <Style.Resources>
+        <Color x:Key='Red'>Red</Color>
+    </Style.Resources>
+</Style>"),
+            new RuntimeXamlLoaderDocument(new Uri("avares://Tests/Folder/Root.xaml"), @"
+<ContentControl xmlns='https://github.com/avaloniaui'
+                xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <ContentControl.Resources>
+        <StyleInclude x:Key='Include' Source='./Style.xaml'/>
     </ContentControl.Resources>
 </ContentControl>")
         };