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Merged
imurashka merged 2 commits into from
Sep 6, 2025
Merged

Allow class unions #23

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3e7f0b4
Allow class unions
imurashka Sep 6, 2025
51c36e0
Allow class unions
imurashka Sep 6, 2025
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2 changes: 1 addition & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator.Shapes/Shapes/Attributes/ExposeAttribute.cs
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Expand Up @@ -2,7 +2,7 @@

namespace Appegy.Union
{
[AttributeUsage(AttributeTargets.Struct | AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
[AttributeUsage(AttributeTargets.Struct | AttributeTargets.Class, Inherited = false)]
public class ExposeAttribute : Attribute
{
public Type[] Interfaces { get; }
Expand Down
2 changes: 1 addition & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator.Shapes/Shapes/Attributes/UnionAttribute.cs
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Expand Up @@ -2,7 +2,7 @@

namespace Appegy.Union
{
[AttributeUsage(System.AttributeTargets.Struct | AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
[AttributeUsage(System.AttributeTargets.Struct | AttributeTargets.Class, Inherited = false)]
public class UnionAttribute : System.Attribute
{
public System.Type[] Types { get; }
Expand Down
6 changes: 3 additions & 3 deletions Appegy.Union.Generator~/Appegy.Union.Generator.Tests/Shapes/ShapePropertyTests.cs
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Expand Up @@ -36,7 +36,7 @@ public void WhenGettingCircle_AndTypeIsNotCircle_ThenThrowsException()
public void WhenSettingCircle_ThenTypeIsCircle()
{
// Arrange
var shape = new Shape();
var shape = new Shape(new Hexagon());
var circle = new Circle(5);

// Act
Expand Down Expand Up @@ -76,7 +76,7 @@ public void WhenGettingRectangle_AndTypeIsNotRectangle_ThenThrowsException()
public void WhenSettingRectangle_ThenTypeIsRectangle()
{
// Arrange
var shape = new Shape();
var shape = new Shape(new Hexagon());
var rectangle = new Rectangle(4, 6);

// Act
Expand Down Expand Up @@ -116,7 +116,7 @@ public void WhenGettingHexagon_AndTypeIsNotHexagon_ThenThrowsException()
public void WhenSettingHexagon_ThenTypeIsHexagon()
{
// Arrange
var shape = new Shape();
var shape = new Shape(new Circle());
var hexagon = new Hexagon(3);

// Act
Expand Down
8 changes: 0 additions & 8 deletions Appegy.Union.Generator~/Appegy.Union.Generator/DiagnosticDescriptors.cs
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Expand Up @@ -6,14 +6,6 @@ public static class DiagnosticDescriptors
{
private const string Category = "Union";

public static DiagnosticDescriptor NotStruct { get; } = new(
id: "UNION001",
title: "Type has to be struct",
messageFormat: "The type '{0}' must be a struct to use [Union].",
category: Category,
defaultSeverity: DiagnosticSeverity.Error,
isEnabledByDefault: true);

public static DiagnosticDescriptor NotPartial { get; } = new(
id: "UNION002",
title: "Struct is not partial",
Expand Down
14 changes: 7 additions & 7 deletions Appegy.Union.Generator~/Appegy.Union.Generator/Expose/ExposeAttributeGenerator.cs
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Expand Up @@ -36,11 +36,11 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
.SyntaxProvider
.ForAttributeWithMetadataName(
ExposeAttributeName,
predicate: static (syntax, _) => syntax is StructDeclarationSyntax,
predicate: static (syntax, _) => syntax is TypeDeclarationSyntax,
transform: static (ctx, _) =>
{
var syntax = (StructDeclarationSyntax)ctx.TargetNode;
var symbol = ctx.SemanticModel.GetDeclaredSymbol(syntax) as INamedTypeSymbol;
var syntax = (TypeDeclarationSyntax)ctx.TargetNode;
var symbol = ctx.SemanticModel.GetDeclaredSymbol(syntax);
var attribute = ctx.Attributes.First();
var interfaces = attribute
.GetTypesFromConstructor(TypeKind.Interface)
Expand All @@ -53,14 +53,14 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
.SyntaxProvider
.ForAttributeWithMetadataName(
UnionAttributeName,
predicate: static (syntax, _) => syntax is StructDeclarationSyntax,
predicate: static (syntax, _) => syntax is TypeDeclarationSyntax,
transform: static (ctx, _) =>
{
var syntax = (StructDeclarationSyntax)ctx.TargetNode;
var symbol = ctx.SemanticModel.GetDeclaredSymbol(syntax) as INamedTypeSymbol;
var syntax = (TypeDeclarationSyntax)ctx.TargetNode;
var symbol = ctx.SemanticModel.GetDeclaredSymbol(syntax);
var attribute = ctx.Attributes.First();
var types = attribute
.GetTypesFromConstructor(TypeKind.Struct)
.GetTypesFromConstructor()
.Select(c => new ExposeTypeInfo(c))
.ToImmutableList();
return (Symbol: symbol!, Types: types);
Expand Down
2 changes: 1 addition & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator/Expose/ExposeAttributePartInput.cs
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Expand Up @@ -4,7 +4,7 @@

namespace Appegy.Union.Generator;

public record struct ExposeAttributePartInput(StructDeclarationSyntax Syntax, IReadOnlyList<ExposeTypeInfo> Types, IReadOnlyList<ExposeInterfaceInfo> Interfaces);
public record struct ExposeAttributePartInput(TypeDeclarationSyntax Syntax, IReadOnlyList<ExposeTypeInfo> Types, IReadOnlyList<ExposeInterfaceInfo> Interfaces);

public readonly struct ExposeTypeInfo(INamedTypeSymbol symbol)
{
Expand Down
14 changes: 13 additions & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator/Expose/Parts/ExposeDeclarationPart.cs
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@@ -1,4 +1,5 @@
using System.CodeDom.Compiler;
using Microsoft.CodeAnalysis.CSharp.Syntax;

namespace Appegy.Union.Generator;

Expand All @@ -8,7 +9,18 @@ public override void Generate(IndentedTextWriter codeWriter, ExposeAttributePart
{
var (syntax, _, interfaces) = input;

codeWriter.Write("partial struct ");
codeWriter.Write("partial ");

switch (syntax)
{
case StructDeclarationSyntax:
codeWriter.Write("struct ");
break;
case ClassDeclarationSyntax:
codeWriter.Write("class ");
break;
}

codeWriter.Write(syntax.Identifier.Text);

codeWriter.WriteLine(" :");
Expand Down
12 changes: 11 additions & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator/Union/Parts/UnionDeclarationPart.cs
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Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
using System.CodeDom.Compiler;
using Microsoft.CodeAnalysis.CSharp.Syntax;

namespace Appegy.Union.Generator;

Expand All @@ -10,7 +11,16 @@ public override void Generate(IndentedTextWriter codeWriter, UnionAttributePartI
var types = input.Types;

codeWriter.WriteLine(AttributesNames.GeneratedCodeAttribute);
codeWriter.Write("partial struct ");
codeWriter.Write("partial ");
switch (syntax)
{
case StructDeclarationSyntax:
codeWriter.Write("struct ");
break;
case ClassDeclarationSyntax:
codeWriter.Write("class ");
break;
}
codeWriter.WriteLine(syntax.Identifier.Text);

codeWriter.Write(" : global::System.IEquatable<");
Expand Down
42 changes: 6 additions & 36 deletions Appegy.Union.Generator~/Appegy.Union.Generator/Union/UnionAttributeAnalyzer.cs
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Expand Up @@ -17,7 +17,6 @@ public class UnionAttributeAnalyzer : DiagnosticAnalyzer
NotPartial,
NestedNotPartial,
NoTypesProvided,
NotStruct,
DuplicateUnionType);

public override void Initialize(AnalysisContext context)
Expand All @@ -39,38 +38,37 @@ private void AnalyzeAttribute(SyntaxNodeAnalysisContext context)
VerifyPartialModifier(context, attributeSyntax);
VerifyParentsPartial(context, attributeSyntax);
VerifyArgumentsExistence(context, attributeSyntax);
VerifyAllTypesAreStruct(context, attributeSyntax);
VerifyNoDuplicate(context, attributeSyntax);
}

private static void VerifyPartialModifier(SyntaxNodeAnalysisContext context, AttributeSyntax attributeSyntax)
{
if (attributeSyntax.Parent?.Parent is not StructDeclarationSyntax structDeclaration)
if (attributeSyntax.Parent?.Parent is not TypeDeclarationSyntax typeDeclaration)
{
return;
}

if (structDeclaration.Modifiers.Any(SyntaxKind.PartialKeyword))
if (typeDeclaration.Modifiers.Any(SyntaxKind.PartialKeyword))
{
return;
}

var diagnostic = Diagnostic.Create(
NotPartial,
structDeclaration.Identifier.GetLocation(),
structDeclaration.Identifier.Text);
typeDeclaration.Identifier.GetLocation(),
typeDeclaration.Identifier.Text);

context.ReportDiagnostic(diagnostic);
}

private static void VerifyParentsPartial(SyntaxNodeAnalysisContext context, AttributeSyntax attributeSyntax)
{
if (attributeSyntax.Parent?.Parent is not StructDeclarationSyntax structDeclaration)
if (attributeSyntax.Parent?.Parent is not TypeDeclarationSyntax typeDeclaration)
{
return;
}

var parent = structDeclaration.Parent;
var parent = typeDeclaration.Parent;
while (parent is TypeDeclarationSyntax parentType)
{
if (!parentType.Modifiers.Any(SyntaxKind.PartialKeyword))
Expand Down Expand Up @@ -99,34 +97,6 @@ private void VerifyArgumentsExistence(SyntaxNodeAnalysisContext context, Attribu
context.ReportDiagnostic(diagnostic);
}

private void VerifyAllTypesAreStruct(SyntaxNodeAnalysisContext context, AttributeSyntax attributeSyntax)
{
var arguments = attributeSyntax.ArgumentList?.Arguments;
if (arguments == null || arguments.Value.Count == 0)
{
return;
}

foreach (var argument in arguments)
{
if (argument.Expression is not TypeOfExpressionSyntax typeOfExpression)
{
continue;
}

var typeInfo = context.SemanticModel.GetTypeInfo(typeOfExpression.Type);
if (typeInfo.Type?.TypeKind != TypeKind.Struct)
{
var diagnostic = Diagnostic.Create(
NotStruct,
typeOfExpression.Type.GetLocation(),
typeInfo.Type?.ToDisplayString() ?? "unknown");

context.ReportDiagnostic(diagnostic);
}
}
}

private void VerifyNoDuplicate(SyntaxNodeAnalysisContext context, AttributeSyntax attributeSyntax)
{
var arguments = attributeSyntax.ArgumentList?.Arguments;
Expand Down
6 changes: 3 additions & 3 deletions Appegy.Union.Generator~/Appegy.Union.Generator/Union/UnionAttributeGenerator.cs
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Expand Up @@ -40,14 +40,14 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
.SyntaxProvider
.ForAttributeWithMetadataName(
UnionAttributeName,
predicate: static (syntax, _) => syntax is StructDeclarationSyntax,
predicate: static (syntax, _) => syntax is TypeDeclarationSyntax,
transform: static (ctx, _) =>
{
var syntax = (StructDeclarationSyntax)ctx.TargetNode;
var syntax = (TypeDeclarationSyntax)ctx.TargetNode;
var symbol = ctx.SemanticModel.GetDeclaredSymbol(syntax);
var attribute = ctx.Attributes.First();
var types = attribute
.GetTypesFromConstructor(TypeKind.Struct)
.GetTypesFromConstructor()
.Select(c => new UnionTypeInfo(c))
.ToImmutableList();

Expand Down
2 changes: 1 addition & 1 deletion Appegy.Union.Generator~/Appegy.Union.Generator/Union/UnionAttributePartInput.cs
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Expand Up @@ -4,7 +4,7 @@

namespace Appegy.Union.Generator;

public record struct UnionAttributePartInput(StructDeclarationSyntax Syntax, IReadOnlyList<UnionTypeInfo> Types, bool ExplicitLayout);
public record struct UnionAttributePartInput(TypeDeclarationSyntax Syntax, IReadOnlyList<UnionTypeInfo> Types, bool ExplicitLayout);

public readonly struct UnionTypeInfo(INamedTypeSymbol symbol)
{
Expand Down
4 changes: 2 additions & 2 deletions Runtime/Appegy.Union.Generator.dll
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2 changes: 1 addition & 1 deletion Runtime/ExposeAttribute.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

namespace Appegy.Union
{
[AttributeUsage(AttributeTargets.Struct)]
[AttributeUsage(AttributeTargets.Struct | AttributeTargets.Class, Inherited = false)]
public class ExposeAttribute : Attribute
{
public Type[] Interfaces { get; }
Expand Down
2 changes: 1 addition & 1 deletion Runtime/UnionAttribute.cs
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Expand Up @@ -2,7 +2,7 @@

namespace Appegy.Union
{
[AttributeUsage(AttributeTargets.Struct)]
[AttributeUsage(AttributeTargets.Struct | AttributeTargets.Class, Inherited = false)]
public class UnionAttribute : Attribute
{
public Type[] Types { get; }
Expand Down