Support nested union types with internal outer classes

Source/FunicularSwitch.Generators/FunicularSwitch.Generators.csproj

@@ -23,7 +23,7 @@
 
 		<!--#region adapt versions here-->
 		<MajorVersion>4</MajorVersion>
-		<MinorAndPatchVersion>2.0</MinorAndPatchVersion>
+		<MinorAndPatchVersion>2.1</MinorAndPatchVersion>
 		<!--#endregion-->
 
 		<AssemblyVersion>$(MajorVersion).0.0</AssemblyVersion>

Source/FunicularSwitch.Generators/UnionType/Generator.cs

@@ -92,7 +92,10 @@ static void WritePartialWithStaticFactories(UnionTypeSchema unionTypeSchema, CSh
         var typeParameters = RoslynExtensions.FormatTypeParameters(unionTypeSchema.TypeParameters);
 
         var typeKind = GetTypeKind(unionTypeSchema);
-        builder.WriteLine($"{(unionTypeSchema.Modifiers.ToSeparatedString(" "))} {typeKind} {unionTypeSchema.TypeName}{typeParameters}");
+        var actualModifiers = unionTypeSchema.Modifiers
+            .Select(m => m == "public" ? (unionTypeSchema.IsInternal ? "internal" : "public") : m);
+
+        builder.WriteLine($"{(actualModifiers.ToSeparatedString(" "))} {typeKind} {unionTypeSchema.TypeName}{typeParameters}");
         using (builder.Scope())
         {
             foreach (var derivedType in unionTypeSchema.Cases)

Source/FunicularSwitch.Generators/UnionType/Parser.cs

@@ -1,5 +1,4 @@
 using System.Collections.Immutable;
-using CommunityToolkit.Mvvm.SourceGenerators.Helpers;
 using FunicularSwitch.Generators.Common;
 using FunicularSwitch.Generators.Generation;
 using Microsoft.CodeAnalysis;
@@ -22,7 +21,7 @@ public static GenerationResult<UnionTypeSchema> GetUnionTypeSchema(Compilation c
 
         var fullTypeName = unionTypeSymbol.FullTypeNameWithNamespace();
         var fullTypeNameWithTypeParameters = fullTypeName + RoslynExtensions.FormatTypeParameters(typeParameters);
-        var acc = unionTypeSymbol.DeclaredAccessibility;
+        var acc = unionTypeSymbol.GetActualAccessibility();
         if (acc is Accessibility.Private or Accessibility.Protected)
         {
             var diag = Diagnostics.UnionTypeIsNotAccessible($"{fullTypeName} needs at least internal accessibility", unionTypeClass.GetLocation());
@@ -44,7 +43,8 @@ public static GenerationResult<UnionTypeSchema> GetUnionTypeSchema(Compilation c
         });
 
 
-        var isPartial = unionTypeClass.Modifiers.HasModifier(SyntaxKind.PartialKeyword);
+        var isPartial = unionTypeClass.Modifiers.HasModifier(SyntaxKind.PartialKeyword)
+            && unionTypeSymbol.ContainingType == null; //for now do not generate factory methods for nested types, we could support that if all containing types are partial
         var generateFactoryMethods = isPartial && staticFactoryMethods;
 
         return

Source/Tests/FunicularSwitch.Generators.Test/Snapshots/Run_union_type_generator.Static_factories_for_nested_internal_union_type#Attributes.g.00.verified.cs

@@ -0,0 +1,40 @@
+//HintName: Attributes.g.cs
+using System;
+
+// ReSharper disable once CheckNamespace
+namespace FunicularSwitch.Generators
+{
+	/// <summary>
+	/// Mark an abstract partial type with a single generic argument with the ResultType attribute.
+	/// This type from now on has Ok | Error semantics with map and bind operations.
+	/// </summary>
+    [AttributeUsage(AttributeTargets.Class, Inherited = false)]
+    sealed class ResultTypeAttribute : Attribute
+    {
+        public ResultTypeAttribute() => ErrorType = typeof(string);
+        public ResultTypeAttribute(Type errorType) => ErrorType = errorType;
+
+        public Type ErrorType { get; set; }
+    }
+
+    /// <summary>
+    /// Mark a static method or a member method or you error type with the MergeErrorAttribute attribute.
+    /// Static signature: TError -> TError -> TError. Member signature: TError -> TError
+    /// We are now able to collect errors and methods like Validate, Aggregate, FirstOk that are useful to combine results are generated.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+    sealed class MergeErrorAttribute : Attribute
+    {
+    }
+
+    /// <summary>
+    /// Mark a static method with the ExceptionToError attribute.
+    /// Signature: Exception -> TError
+    /// This method is always called, when an exception happens in a bind operation.
+    /// So a call like result.Map(i => i/0) will return an Error produced by the factory method instead of throwing the DivisionByZero exception.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+    sealed class ExceptionToError : Attribute
+    {
+    }
+}

Source/Tests/FunicularSwitch.Generators.Test/Snapshots/Run_union_type_generator.Static_factories_for_nested_internal_union_type#Attributes.g.01.verified.cs

@@ -0,0 +1,28 @@
+//HintName: Attributes.g.cs
+using System;
+
+// ReSharper disable once CheckNamespace
+namespace FunicularSwitch.Generators
+{
+    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Interface, Inherited = false)]
+    sealed class UnionTypeAttribute : Attribute
+    {
+        public CaseOrder CaseOrder { get; set; } = CaseOrder.Alphabetic;
+        public bool StaticFactoryMethods { get; set; } = true;
+    }
+
+    enum CaseOrder
+    {
+        Alphabetic,
+        AsDeclared,
+        Explicit
+    }
+
+    [AttributeUsage(AttributeTargets.Class, Inherited = false)]
+    sealed class UnionCaseAttribute : Attribute
+    {
+        public UnionCaseAttribute(int index) => Index = index;
+
+        public int Index { get; }
+    }
+}

Source/Tests/FunicularSwitch.Generators.Test/Snapshots/Run_union_type_generator.Static_factories_for_nested_internal_union_type#Attributes.g.02.verified.cs

@@ -0,0 +1,61 @@
+//HintName: Attributes.g.cs
+using System;
+
+// ReSharper disable once CheckNamespace
+namespace FunicularSwitch.Generators
+{
+    [AttributeUsage(AttributeTargets.Enum)]
+    sealed class ExtendedEnumAttribute : Attribute
+    {
+	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;
+	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;
+    }
+
+    enum EnumCaseOrder
+    {
+        Alphabetic,
+        AsDeclared
+    }
+
+    /// <summary>
+    /// Generate match methods for all enums defined in assembly that contains AssemblySpecifier.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
+    class ExtendEnumsAttribute : Attribute
+    {
+	    public Type AssemblySpecifier { get; }
+	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;
+	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;
+
+	    public ExtendEnumsAttribute() => AssemblySpecifier = typeof(ExtendEnumsAttribute);
+
+	    public ExtendEnumsAttribute(Type assemblySpecifier)
+	    {
+		    AssemblySpecifier = assemblySpecifier;
+	    }
+    }
+
+    /// <summary>
+    /// Generate match methods for Type. Must be enum.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = true)]
+    class ExtendEnumAttribute : Attribute
+    {
+	    public Type Type { get; }
+
+	    public EnumCaseOrder CaseOrder { get; set; } = EnumCaseOrder.AsDeclared;
+
+	    public ExtensionAccessibility Accessibility { get; set; } = ExtensionAccessibility.Public;
+
+	    public ExtendEnumAttribute(Type type)
+	    {
+		    Type = type;
+	    }
+    }
+
+    enum ExtensionAccessibility
+    {
+	    Internal,
+	    Public
+    }
+}

Source/Tests/FunicularSwitch.Generators.Test/Snapshots/Run_union_type_generator.Static_factories_for_nested_internal_union_type#FunicularSwitchTestOuterInitResultMatchExtension.g.verified.cs

@@ -0,0 +1,74 @@
+//HintName: FunicularSwitchTestOuterInitResultMatchExtension.g.cs
+#pragma warning disable 1591
+namespace FunicularSwitch.Test
+{
+	internal static partial class InitResultMatchExtension
+	{
+		public static T Match<T>(this FunicularSwitch.Test.Outer.InitResult initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, T> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, T> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, T> noSync) =>
+		initResult switch
+		{
+			FunicularSwitch.Test.Outer.InitResult.Sync_ sync1 => sync(sync1),
+			FunicularSwitch.Test.Outer.InitResult.OneTimeSync_ oneTimeSync2 => oneTimeSync(oneTimeSync2),
+			FunicularSwitch.Test.Outer.InitResult.NoSync_ noSync3 => noSync(noSync3),
+			_ => throw new global::System.ArgumentException($"Unknown type derived from FunicularSwitch.Test.Outer.InitResult: {initResult.GetType().Name}")
+		};
+
+		public static global::System.Threading.Tasks.Task<T> Match<T>(this FunicularSwitch.Test.Outer.InitResult initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, global::System.Threading.Tasks.Task<T>> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, global::System.Threading.Tasks.Task<T>> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, global::System.Threading.Tasks.Task<T>> noSync) =>
+		initResult switch
+		{
+			FunicularSwitch.Test.Outer.InitResult.Sync_ sync1 => sync(sync1),
+			FunicularSwitch.Test.Outer.InitResult.OneTimeSync_ oneTimeSync2 => oneTimeSync(oneTimeSync2),
+			FunicularSwitch.Test.Outer.InitResult.NoSync_ noSync3 => noSync(noSync3),
+			_ => throw new global::System.ArgumentException($"Unknown type derived from FunicularSwitch.Test.Outer.InitResult: {initResult.GetType().Name}")
+		};
+
+		public static async global::System.Threading.Tasks.Task<T> Match<T>(this global::System.Threading.Tasks.Task<FunicularSwitch.Test.Outer.InitResult> initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, T> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, T> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, T> noSync) =>
+		(await initResult.ConfigureAwait(false)).Match(sync, oneTimeSync, noSync);
+
+		public static async global::System.Threading.Tasks.Task<T> Match<T>(this global::System.Threading.Tasks.Task<FunicularSwitch.Test.Outer.InitResult> initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, global::System.Threading.Tasks.Task<T>> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, global::System.Threading.Tasks.Task<T>> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, global::System.Threading.Tasks.Task<T>> noSync) =>
+		await (await initResult.ConfigureAwait(false)).Match(sync, oneTimeSync, noSync).ConfigureAwait(false);
+
+		public static void Switch(this FunicularSwitch.Test.Outer.InitResult initResult, global::System.Action<FunicularSwitch.Test.Outer.InitResult.Sync_> sync, global::System.Action<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_> oneTimeSync, global::System.Action<FunicularSwitch.Test.Outer.InitResult.NoSync_> noSync)
+		{
+			switch (initResult)
+			{
+				case FunicularSwitch.Test.Outer.InitResult.Sync_ sync1:
+					sync(sync1);
+					break;
+				case FunicularSwitch.Test.Outer.InitResult.OneTimeSync_ oneTimeSync2:
+					oneTimeSync(oneTimeSync2);
+					break;
+				case FunicularSwitch.Test.Outer.InitResult.NoSync_ noSync3:
+					noSync(noSync3);
+					break;
+				default:
+					throw new global::System.ArgumentException($"Unknown type derived from FunicularSwitch.Test.Outer.InitResult: {initResult.GetType().Name}");
+			}
+		}
+
+		public static async global::System.Threading.Tasks.Task Switch(this FunicularSwitch.Test.Outer.InitResult initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, global::System.Threading.Tasks.Task> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, global::System.Threading.Tasks.Task> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, global::System.Threading.Tasks.Task> noSync)
+		{
+			switch (initResult)
+			{
+				case FunicularSwitch.Test.Outer.InitResult.Sync_ sync1:
+					await sync(sync1).ConfigureAwait(false);
+					break;
+				case FunicularSwitch.Test.Outer.InitResult.OneTimeSync_ oneTimeSync2:
+					await oneTimeSync(oneTimeSync2).ConfigureAwait(false);
+					break;
+				case FunicularSwitch.Test.Outer.InitResult.NoSync_ noSync3:
+					await noSync(noSync3).ConfigureAwait(false);
+					break;
+				default:
+					throw new global::System.ArgumentException($"Unknown type derived from FunicularSwitch.Test.Outer.InitResult: {initResult.GetType().Name}");
+			}
+		}
+
+		public static async global::System.Threading.Tasks.Task Switch(this global::System.Threading.Tasks.Task<FunicularSwitch.Test.Outer.InitResult> initResult, global::System.Action<FunicularSwitch.Test.Outer.InitResult.Sync_> sync, global::System.Action<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_> oneTimeSync, global::System.Action<FunicularSwitch.Test.Outer.InitResult.NoSync_> noSync) =>
+		(await initResult.ConfigureAwait(false)).Switch(sync, oneTimeSync, noSync);
+
+		public static async global::System.Threading.Tasks.Task Switch(this global::System.Threading.Tasks.Task<FunicularSwitch.Test.Outer.InitResult> initResult, global::System.Func<FunicularSwitch.Test.Outer.InitResult.Sync_, global::System.Threading.Tasks.Task> sync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.OneTimeSync_, global::System.Threading.Tasks.Task> oneTimeSync, global::System.Func<FunicularSwitch.Test.Outer.InitResult.NoSync_, global::System.Threading.Tasks.Task> noSync) =>
+		await (await initResult.ConfigureAwait(false)).Switch(sync, oneTimeSync, noSync).ConfigureAwait(false);
+	}
+}
+#pragma warning restore 1591

Source/Tests/FunicularSwitch.Generators.Test/UnionTypeGeneratorSpecs.cs

@@ -337,8 +337,31 @@ class Consumer {
 		return Verify(code);
 	}
 
+    [TestMethod]
+    public Task Static_factories_for_nested_internal_union_type()
+    {
+        var code = @"
+using FunicularSwitch.Generators;
+
+namespace FunicularSwitch.Test;
+
+static class Outer
+{
+ [UnionType(CaseOrder = CaseOrder.AsDeclared)]
+ public partial record InitResult
+ {
+   public record Sync_ : InitResult;
+   public record OneTimeSync_(string TempRepoFolder) : InitResult;
+   public record NoSync_() : InitResult;
+ }
+}";
+
+        return Verify(code);
+    }
+
+
 	[TestMethod]
-	public Task No_static_factories_for_interface_union_type()
+	public Task Static_factories_for_interface_union_type()
 	{
 		var code = @"
 using FunicularSwitch.Generators;