UnionType Update

Directory.Packages.props

@@ -10,7 +10,6 @@
     <!-- <PackageVersion Include="Microsoft.Net.Compilers.Toolset" Version="5.0.0" /> -->
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.4.0" />
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="10.0.202" />
-    <PackageVersion Include="N.SourceGenerators.UnionTypes" Version="0.28.2" />
     <PackageVersion Include="Nerdbank.GitVersioning" Version="3.9.50" />
     <PackageVersion Include="PolySharp" Version="1.15.0" />
     <PackageVersion Include="StyleCop.Analyzers" Version="1.2.0-beta.556" />

src/Directory.Build.props

@@ -23,6 +23,7 @@
   </PropertyGroup> 
 
   <ItemGroup>
+    <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\CompilerServices\UnionAttribute.cs" Link="System\Runtime\CompilerServices\UnionAttribute.cs" />
     <None Include="$(MSBuildThisFileDirectory)images\icon.png" Pack="true" PackagePath="\"/>
   </ItemGroup>
 

src/System/Runtime/CompilerServices/UnionAttribute.cs

@@ -0,0 +1,7 @@
+namespace System.Runtime.CompilerServices;
+
+/// <summary>
+/// Marks a type as a C# union.
+/// </summary>
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct, AllowMultiple = false)]
+public sealed class UnionAttribute : Attribute;

src/Zomp.SyncMethodGenerator/AsyncToSyncRewriter.cs

@@ -376,8 +376,8 @@ bool IsValidParameter(ParameterSyntax ps, int i)
             var extra = ProcessTrivia(leading, ds);
             if (extra is not null && extra.AdditionalStatements.Count > 0)
             {
-                modifications.Add(i, new List<StatementSyntax>(extra.AdditionalStatements));
-                modifications.Add(i + 1, true);
+                modifications.Add(i, new Operation([.. extra.AdditionalStatements]));
+                modifications.Add(i + 1, new Operation(true));
             }
 
             if (semanticModel.GetDeclaredSymbol(ps) is not { } symbol)
@@ -1074,8 +1074,8 @@ bool ShouldRemoveArgumentLocal(ArgumentSyntax arg, int index)
 
             if (extra is { AdditionalStatements.Count: > 0 })
             {
-                modifications.Add(index, new List<StatementSyntax>(extra.AdditionalStatements));
-                modifications.Add(index + 1, true);
+                modifications.Add(index, new Operation([.. extra.AdditionalStatements]));
+                modifications.Add(index + 1, new Operation(true));
             }
 
             if (byExpression || nullableParameters is not { } parameters)

src/Zomp.SyncMethodGenerator/Operation.cs

@@ -1,7 +1,41 @@
 namespace Zomp.SyncMethodGenerator;
 
-[N.SourceGenerators.UnionTypes.UnionType(typeof(List<StatementSyntax>), "NewStatements")]
-[N.SourceGenerators.UnionTypes.UnionType(typeof(bool), "RemoveLeadingEndIf")]
-internal sealed partial class Operation
+/// <summary>
+/// Represents a sync-only operation.
+/// </summary>
+[Union]
+internal readonly struct Operation
 {
+    /// <summary>
+    /// Initializes a new instance of the <see cref="Operation"/> struct.
+    /// </summary>
+    /// <param name="value">The new statements to insert.</param>
+    public Operation(List<StatementSyntax> value)
+    {
+        Value = value;
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="Operation"/> struct.
+    /// </summary>
+    /// <param name="value">A value indicating whether to remove the leading end-if directive.</param>
+    public Operation(bool value)
+    {
+        Value = value;
+    }
+
+    /// <summary>
+    /// Gets the active operation value.
+    /// </summary>
+    public object? Value { get; }
+
+    /// <summary>
+    /// Gets a value indicating whether the operation inserts new statements.
+    /// </summary>
+    public bool IsNewStatements => Value is List<StatementSyntax>;
+
+    /// <summary>
+    /// Gets the operation value as new statements.
+    /// </summary>
+    public List<StatementSyntax> AsNewStatements => (List<StatementSyntax>)Value!;
 }

src/Zomp.SyncMethodGenerator/Zomp.SyncMethodGenerator.csproj

@@ -49,7 +49,6 @@
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" PrivateAssets="all" Pack="false" />
     <PackageReference Include="Microsoft.Bcl.HashCode" PrivateAssets="all" GeneratePathProperty="true" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp" PrivateAssets="all" Pack="false" />
-    <PackageReference Include="N.SourceGenerators.UnionTypes" PrivateAssets="all" Pack="false" />
     <PackageReference Include="Nerdbank.GitVersioning" PrivateAssets="all" IncludeAssets="runtime; build; native; contentfiles; analyzers" />
     <PackageReference Include="PolySharp" PrivateAssets="all" IncludeAssets="runtime; build; native; contentfiles; analyzers; buildtransitive" />
     <!-- <PackageReference Include="Microsoft.Net.Compilers.Toolset" PrivateAssets="all" IncludeAssets="runtime; build; native; contentfiles; analyzers; buildtransitive" /> -->