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Merged
akeit0 merged 2 commits into from
Jan 16, 2026
Merged

Add: support for init/set/get only properties for SourceGenerator #244

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46460ba
add: add support for init/set/get only properties for SourceGenerator
akeit0 Jan 16, 2026
3fcf276
refactor: combine invalid member access case in SourceGenerator
akeit0 Jan 16, 2026
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109 changes: 85 additions & 24 deletions src/Lua.SourceGenerator/LuaObjectGenerator.Emit.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -13,7 +13,8 @@ static string GetLuaValuePrefix(ITypeSymbol typeSymbol, SymbolReferences referen
: "(";
}

static bool TryEmit(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, Compilation compilation, in SourceProductionContext context, Dictionary<INamedTypeSymbol, TypeMetadata> metaDict)
static bool TryEmit(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, Compilation compilation, in SourceProductionContext context, Dictionary<INamedTypeSymbol, TypeMetadata> metaDict,
TempCollections tempCollections)
{
try
{
Expand Down Expand Up @@ -87,19 +88,19 @@ static bool TryEmit(TypeMetadata typeMetadata, CodeBuilder builder, SymbolRefere

using var _ = builder.BeginBlockScope($"partial {typeDeclarationKeyword} {typeMetadata.TypeName} : global::Lua.ILuaUserData");

var metamethodSet = new HashSet<LuaObjectMetamethod>();
var metamethodSet = tempCollections.Metamethods;

if (!TryEmitMethods(typeMetadata, builder, references, compilation, metamethodSet, context))
{
return false;
}

if (!TryEmitIndexMetamethod(typeMetadata, builder, references, compilation, context))
if (!TryEmitIndexMetamethod(typeMetadata, builder, references, compilation, context, tempCollections))
{
return false;
}

if (!TryEmitNewIndexMetamethod(typeMetadata, builder, references, context))
if (!TryEmitNewIndexMetamethod(typeMetadata, builder, references, context, tempCollections))
{
return false;
}
Expand Down Expand Up @@ -269,20 +270,26 @@ static bool ValidateMembers(TypeMetadata typeMetadata, Compilation compilation,
return isValid;
}

static bool TryEmitIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, Compilation compilation, in SourceProductionContext context)
static bool TryEmitIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, Compilation compilation, in SourceProductionContext context, TempCollections tempCollections)
{
builder.AppendLine(@"static readonly global::Lua.LuaFunction __metamethod_index = new global::Lua.LuaFunction(""index"", (context, ct) =>");

using (builder.BeginBlockScope())
{
builder.AppendLine($"var userData = context.GetArgument<{typeMetadata.FullTypeName}>(0);");
builder.AppendLine($"var key = context.GetArgument<global::System.String>(1);");
builder.AppendLine("var key = context.GetArgument<global::System.String>(1);");
builder.AppendLine("var result = key switch");

using (builder.BeginBlockScope())
{
foreach (var propertyMetadata in typeMetadata.Properties)
{
if (propertyMetadata.IsWriteOnly)
{
tempCollections.InvalidMemberNames.Add(propertyMetadata.LuaMemberName);
continue;
}


var conversionPrefix = GetLuaValuePrefix(propertyMetadata.Type, references, compilation);
if (propertyMetadata.IsStatic)
{
Expand All @@ -300,7 +307,35 @@ static bool TryEmitIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builde
builder.AppendLine(@$"""{methodMetadata.LuaMemberName}"" => new global::Lua.LuaValue(__function_{methodMetadata.LuaMemberName}),");
}

builder.AppendLine(@$"_ => global::Lua.LuaValue.Nil,");
builder.Append("_ => ");
{
if (tempCollections.InvalidMemberNames.Count > 0)
{
builder.Append("(key is ", false);
for (var index = 0; index < tempCollections.InvalidMemberNames.Count; index++)
{
var name = tempCollections.InvalidMemberNames[index];
builder.Append("\"", false);
builder.Append(name, false);
builder.Append("\"", false);
if (index < tempCollections.InvalidMemberNames.Count - 1)
{
builder.Append(" or ", false);
}
}

builder.AppendLine(")", false);
using (builder.BeginIndentScope())
{
builder.AppendLine(@"? throw new global::Lua.LuaRuntimeException(context.State, $""'{key}' cannot be read."")");
builder.AppendLine(": global::Lua.LuaValue.Nil,");
}

tempCollections.InvalidMemberNames.Clear();
}
else
builder.AppendLine(@"global::Lua.LuaValue.Nil,");
}
}

builder.AppendLine(";");
Expand All @@ -313,29 +348,31 @@ static bool TryEmitIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builde
return true;
}

static bool TryEmitNewIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, in SourceProductionContext context)
static bool TryEmitNewIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder builder, SymbolReferences references, in SourceProductionContext context, TempCollections tempCollections)
{
builder.AppendLine(@"static readonly global::Lua.LuaFunction __metamethod_newindex = new global::Lua.LuaFunction(""newindex"", (context, ct) =>");

using (builder.BeginBlockScope())
{
builder.AppendLine($"var userData = context.GetArgument<{typeMetadata.FullTypeName}>(0);");
builder.AppendLine($"var key = context.GetArgument<global::System.String>(1);");
builder.AppendLine("var key = context.GetArgument<global::System.String>(1);");
builder.AppendLine("switch (key)");

using (builder.BeginBlockScope())
{
foreach (var propertyMetadata in typeMetadata.Properties)
{
if (propertyMetadata.IsReadOnly)
{
tempCollections.InvalidMemberNames.Add(propertyMetadata.LuaMemberName);
continue;
}

builder.AppendLine(@$"case ""{propertyMetadata.LuaMemberName}"":");

using (builder.BeginIndentScope())
{
if (propertyMetadata.IsReadOnly)
{
builder.AppendLine($@"throw new global::Lua.LuaRuntimeException(context.State, $""'{{key}}' cannot overwrite."");");
}
else if (propertyMetadata.IsStatic)
if (propertyMetadata.IsStatic)
{
if (SymbolEqualityComparer.Default.Equals(propertyMetadata.Type, references.LuaValue))
{
Expand Down Expand Up @@ -367,19 +404,42 @@ static bool TryEmitNewIndexMetamethod(TypeMetadata typeMetadata, CodeBuilder bui
foreach (var methodMetadata in typeMetadata.Methods
.Where(x => x.HasMemberAttribute))
{
builder.AppendLine(@$"case ""{methodMetadata.LuaMemberName}"":");

using (builder.BeginIndentScope())
{
builder.AppendLine($@"throw new global::Lua.LuaRuntimeException(context.State, $""'{{key}}' cannot overwrite."");");
}
tempCollections.InvalidMemberNames.Add(methodMetadata.LuaMemberName);
}

builder.AppendLine(@$"default:");
builder.AppendLine(@"default:");

using (builder.BeginIndentScope())
{
builder.AppendLine(@$"throw new global::Lua.LuaRuntimeException(context.State, $""'{{key}}' not found."");");
if (tempCollections.InvalidMemberNames.Count > 0)
{
builder.AppendLine("throw new global::Lua.LuaRuntimeException(context.State,");
using (builder.BeginIndentScope())
{
builder.Append("(key is ");
for (var index = 0; index < tempCollections.InvalidMemberNames.Count; index++)
{
var name = tempCollections.InvalidMemberNames[index];
builder.Append("\"", false);
builder.Append(name, false);
builder.Append("\"", false);
if (index < tempCollections.InvalidMemberNames.Count - 1)
{
builder.Append(" or ", false);
}
}

builder.AppendLine(")", false);
using (builder.BeginIndentScope())
{
builder.AppendLine(@"? $""'{key}' cannot overwrite.""");
tempCollections.InvalidMemberNames.Clear();
builder.AppendLine(@": $""'{key}' not found."");");
}
}
}
else
builder.AppendLine(@"throw new global::Lua.LuaRuntimeException(context.State, $""'{key}' not found."");");
}
}

Expand Down Expand Up @@ -471,7 +531,8 @@ static void EmitMethodFunction(string functionName, string chunkName, TypeMetada
}
else
{
builder.AppendLine($"var arg{index} = context.HasArgument({index}) ? context.GetArgument<{parameterType.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat)}>({index}) : {syntax.Default!.Value.ToFullString()};");
builder.AppendLine(
$"var arg{index} = context.HasArgument({index}) ? context.GetArgument<{parameterType.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat)}>({index}) : {syntax.Default!.Value.ToFullString()};");
}
}
else
Expand Down
4 changes: 3 additions & 1 deletion src/Lua.SourceGenerator/LuaObjectGenerator.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -39,10 +39,11 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
metaDict.Add(symbol, typeMeta);
}

var tempCollections = new TempCollections();
foreach (var pair in metaDict)
{
var typeMeta = pair.Value;
if (TryEmit(typeMeta, builder, references, compilation, in sourceProductionContext, metaDict))
if (TryEmit(typeMeta, builder, references, compilation, in sourceProductionContext, metaDict, tempCollections))
{
var fullType = typeMeta.FullTypeName
.Replace("global::", "")
Expand All @@ -52,6 +53,7 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
sourceProductionContext.AddSource($"{fullType}.LuaObject.g.cs", builder.ToString());
}

tempCollections.Clear();
builder.Clear();
}
});
Expand Down
4 changes: 3 additions & 1 deletion src/Lua.SourceGenerator/PropertyMetadata.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@ public class PropertyMetadata
public string TypeFullName { get; }
public bool IsStatic { get; }
public bool IsReadOnly { get; }
public bool IsWriteOnly { get; }
public string LuaMemberName { get; }

public PropertyMetadata(ISymbol symbol, SymbolReferences references)
Expand All @@ -27,7 +28,8 @@ public PropertyMetadata(ISymbol symbol, SymbolReferences references)
{
Type = property.Type;
TypeFullName = property.Type.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat);
IsReadOnly = property.SetMethod == null;
IsReadOnly = property.IsReadOnly || property.SetMethod == null || property.SetMethod.IsInitOnly;
IsWriteOnly = property.IsWriteOnly;
}
else
{
Expand Down
12 changes: 12 additions & 0 deletions src/Lua.SourceGenerator/TempCollections.cs
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Original file line number Diff line number Diff line change
@@ -0,0 +1,12 @@
namespace Lua.SourceGenerator;

class TempCollections
{
public readonly HashSet<LuaObjectMetamethod> Metamethods = new();
public readonly List<string> InvalidMemberNames = new();
public void Clear()
{
Metamethods.Clear();
InvalidMemberNames.Clear();
}
}
5 changes: 0 additions & 5 deletions src/Lua.SourceGenerator/TypeMetadata.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -37,11 +37,6 @@ public TypeMetadata(TypeDeclarationSyntax syntax, INamedTypeSymbol symbol, Symbo

if (x is IPropertySymbol p)
{
if (p.GetMethod == null || p.SetMethod == null)
{
return false;
}

if (p.IsIndexer)
{
return false;
Expand Down
54 changes: 27 additions & 27 deletions tests/Lua.Tests/LuaObjectTests.cs
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Original file line number Diff line number Diff line change
@@ -1,59 +1,59 @@
using Lua.Standard;

namespace Lua.Tests;

[LuaObject]
public partial class LuaTestObj {
public partial class LuaTestObj
{
int x;
int y;

[LuaMember("x")]
public int X {
public int X
{
get => x;
set => x = value;
}

[LuaMember("y")]
public int Y {
public int Y
{
get => y;
set => y = value;
}

[LuaMember("create")]
public static LuaTestObj Create(int x, int y) {
return new LuaTestObj() {
x = x,
y = y
};
public static LuaTestObj Create(int x, int y)
{
return new LuaTestObj() { x = x, y = y };
}

[LuaMetamethod(LuaObjectMetamethod.Add)]
public static LuaTestObj Add(LuaTestObj a, LuaTestObj b) {
return new LuaTestObj() {
x = a.x + b.x,
y = a.y + b.y
};
public static LuaTestObj Add(LuaTestObj a, LuaTestObj b)
{
return new LuaTestObj() { x = a.x + b.x, y = a.y + b.y };
}

[LuaMetamethod(LuaObjectMetamethod.Sub)]
public static async Task<LuaTestObj> Sub(LuaTestObj a, LuaTestObj b) {
public static async Task<LuaTestObj> Sub(LuaTestObj a, LuaTestObj b)
{
await Task.Delay(1);
return new LuaTestObj() {
x = a.x - b.x,
y = a.y - b.y
};
return new LuaTestObj() { x = a.x - b.x, y = a.y - b.y };
}
}

[LuaObject]
public partial class TestUserData
{
[LuaMember]
public int Property { get; set; }
[LuaMember] public int Property { get; init; }

[LuaMember]
public LuaValue LuaValueProperty { get; set; }
[LuaMember] public int ReadOnlyProperty { get; }

[LuaMember("p2")]
public string PropertyWithName { get; set; } = "";
[LuaMember] public int SetOnlyProperty { set { } }

[LuaMember] public LuaValue LuaValueProperty { get; set; }

[LuaMember("p2")] public string PropertyWithName { get; set; } = "";

[LuaMember]
public static void MethodVoid()
Expand Down Expand Up @@ -201,15 +201,15 @@ public async Task Test_CallMetamethod()
Assert.That(results, Has.Length.EqualTo(1));
Assert.That(results[0], Is.EqualTo(new LuaValue("Called!")));
}

[Test]
public async Task Test_ArithMetamethod()
{
var userData = new LuaTestObj();

var state = LuaState.Create();
state.OpenBasicLibrary();
state.Environment["TestObj"]=userData;
state.Environment["TestObj"] = userData;
var results = await state.DoStringAsync("""
local a = TestObj.create(1, 2)
local b = TestObj.create(3, 4)
Expand Down