feat: Source Generator for External Classes

src/Avalonia.Markup.Declarative.SourceGenerator/Avalonia.Markup.Declarative.SourceGenerator.csproj

@@ -1,14 +1,17 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <LangVersion>latest</LangVersion>
     <GeneratePackageOnBuild>False</GeneratePackageOnBuild>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <!--<EnforceExtendedAnalyzerRules>true</EnforceExtendedAnalyzerRules>-->  <!--todo enable this and fix errors-->
   </PropertyGroup>
 
   <ItemGroup>
     <PackageReference Include="Avalonia" Version="11.1.3" />
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.12.0-2.final" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.11.0" PrivateAssets="all" />
     <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.11.0" PrivateAssets="all" />
   </ItemGroup>
 

src/Avalonia.Markup.Declarative.SourceGenerator/AvaloniaExtensionsGenerator.cs

@@ -0,0 +1,64 @@
+using System.Collections.Immutable;
+using System.Diagnostics;
+using System.Text;
+using AvaloniaExtensionGenerator;
+using Microsoft.CodeAnalysis;
+
+namespace Avalonia.Markup.Declarative.SourceGenerator;
+
+[Generator]
+public class AvaloniaExtensionsGenerator : ISourceGenerator
+{
+    public void Execute(GeneratorExecutionContext context)
+    {
+#if DEBUG
+        if (!Debugger.IsAttached)
+        {
+            Debugger.Launch();
+        }
+#endif
+        Debug.WriteLine("Execute AvaloniaExtensionsGenerator code generator");
+
+        var comp = context.Compilation;
+        var sb = new StringBuilder();
+        var generator = new GeneratorHost();
+
+        var typeByMetadataName = comp.GetTypeByMetadataName("Avalonia.Markup.Declarative.GenerateMarkupForAssemblyAttribute");
+        var assemblies = ImmutableArray.CreateBuilder<IAssemblySymbol>();
+
+        assemblies.Add(context.Compilation.Assembly);
+
+        foreach (AttributeData attributeData in comp.Assembly.GetAttributes())
+        {
+            var attributeClass = attributeData.AttributeClass;
+            if ((attributeClass != null ? (!attributeClass.Equals(typeByMetadataName, SymbolEqualityComparer.Default) ? 1 : 0) : 1) == 0)
+            {
+                var constructorArgument = attributeData.ConstructorArguments[0];
+
+                if (constructorArgument.Value is INamedTypeSymbol iNamedTypeSymbol)
+                    assemblies.Add(iNamedTypeSymbol.ContainingAssembly);
+            }
+        }
+
+        foreach (IAssemblySymbol assembly in assemblies)
+        {
+            foreach (INamedTypeSymbol publicClass in assembly.GlobalNamespace.GetPublicClasses())
+            {
+                var code = generator.GenerateExtensions(publicClass);
+
+                if (code != null)
+                {
+                    context.AddSource($"{publicClass}.g.cs".TrimStart('.'), code);
+                }
+            }
+        }
+
+        return;
+    }
+
+    public void Initialize(GeneratorInitializationContext context)
+    {
+        Debug.WriteLine("Initialize code generator");
+        // No initialization required for this one
+    }
+}