Use converter for string set

Author: inputfalken

src/DynamoDBGenerator.SourceGenerator/Generations/Marshalling/Marshaller.cs

@@ -120,14 +120,6 @@ or SingleGeneric.SupportedType.IEnumerable
                                 .CreateScope(singleGeneric.ReturnNullOrThrow(DataMember))
                                 .Append($"return {AttributeValueUtilityFactory.FromEnumerable}({ParamReference}, {MarshallerOptions.ParamReference}, {DataMember}, static (a, o, d) => {InvokeMarshallerMethod(singleGeneric.T, "a", "d", options, "o")}{(singleGeneric.T.IsSupposedToBeNull ? $" ?? {AttributeValueUtilityFactory.Null}" : null)});")
                         ).ToConversion(singleGeneric.T),
-                SingleGeneric.SupportedType.Set when singleGeneric.T.TypeSymbol.SpecialType is SpecialType.System_String
-                    => signature
-                        .CreateScope(
-                            $"if ({ParamReference} is null)"
-                                .CreateScope(singleGeneric.ReturnNullOrThrow(DataMember))
-                                .Append($"return new {Constants.AWSSDK_DynamoDBv2.AttributeValue} {{ SS = new List<{(singleGeneric.T.IsSupposedToBeNull ? "string?" : "string")}>({(singleGeneric.T.IsSupposedToBeNull ? ParamReference : $"{ParamReference}.Select((y,i) => y ?? throw {ExceptionHelper.NullExceptionMethod}($\"{{{DataMember}}}[UNKNOWN]\"))")})}};")
-                        )
-                        .ToConversion(singleGeneric.T),
                 SingleGeneric.SupportedType.Set when singleGeneric.T.IsNumeric
                     => signature
                         .CreateScope(

src/DynamoDBGenerator.SourceGenerator/Generations/UnMarshaller.cs

@@ -128,13 +128,6 @@ private static CodeFactory CreateMethod(TypeIdentifier typeIdentifier, Func<ITyp
                             .Append($"return {AttributeValueUtilityFactory.ToEnumerable}({Value}.L, {MarshallerOptions.ParamReference}, {DataMember}, static (a, o, d) => {InvokeUnmarshallMethod(singleGeneric.T, "a", "d", options, "o")});")
                         )
                     .ToConversion(singleGeneric.T),
-                SingleGeneric.SupportedType.Set when singleGeneric.T.TypeSymbol.SpecialType is SpecialType.System_String => signature
-                    .CreateScope(
-                        $"if ({Value} is null || {Value}.SS is null)"
-                            .CreateScope(singleGeneric.ReturnNullOrThrow(DataMember))
-                            .Append($"return new {(singleGeneric.TypeSymbol.TypeKind is TypeKind.Interface ? $"HashSet<{(singleGeneric.T.IsSupposedToBeNull ? "string?" : "string")}>" : null)}({(singleGeneric.T.IsSupposedToBeNull ? $"{Value}.SS" : $"{Value}.SS.Select((y,i) => y ?? throw {ExceptionHelper.NullExceptionMethod}($\"{{{DataMember}}}[UNKNOWN]\")")}));")
-                        )
-                    .ToConversion(),
                 SingleGeneric.SupportedType.Set when singleGeneric.T.IsNumeric => signature
                     .CreateScope(
                         $"if ({Value} is null || {Value}.NS is null)"

src/DynamoDBGenerator/Converters/Internal/StringSetConverter.cs

@@ -0,0 +1,70 @@
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using Amazon.DynamoDBv2.Model;
+using DynamoDBGenerator.Internal;
+
+namespace DynamoDBGenerator.Converters.Internal;
+
+internal sealed class StringSetConverter :
+    IReferenceTypeConverter<IReadOnlySet<string>>,
+    IReferenceTypeConverter<HashSet<string>>,
+    IReferenceTypeConverter<ISet<string>>,
+    IReferenceTypeConverter<SortedSet<string>>,
+    IStaticSingleton<StringSetConverter>
+{
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static HashSet<string>? ToHashSet(AttributeValue attributeValue)
+    {
+        return attributeValue.IsSSSet
+            ? new HashSet<string>(attributeValue.SS)
+            : null;
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private static AttributeValue ToAttributeValue(IEnumerable<string> enumerable)
+    {
+        return new AttributeValue { SS = new List<string>(enumerable) };
+    }
+
+    IReadOnlySet<string>? IReferenceTypeConverter<IReadOnlySet<string>>.Read(AttributeValue attributeValue)
+    {
+        return ToHashSet(attributeValue);
+    }
+
+    ISet<string>? IReferenceTypeConverter<ISet<string>>.Read(AttributeValue attributeValue)
+    {
+        return ToHashSet(attributeValue);
+    }
+
+    HashSet<string>? IReferenceTypeConverter<HashSet<string>>.Read(AttributeValue attributeValue)
+    {
+        return ToHashSet(attributeValue);
+    }
+
+    SortedSet<string>? IReferenceTypeConverter<SortedSet<string>>.Read(AttributeValue attributeValue)
+    {
+        return attributeValue.IsSSSet
+            ? new SortedSet<string>(attributeValue.SS)
+            : null;
+    }
+
+    AttributeValue IReferenceTypeConverter<SortedSet<string>>.Write(SortedSet<string> element)
+    {
+        return ToAttributeValue(element);
+    }
+
+    AttributeValue IReferenceTypeConverter<ISet<string>>.Write(ISet<string> element)
+    {
+        return ToAttributeValue(element);
+    }
+
+    AttributeValue IReferenceTypeConverter<HashSet<string>>.Write(HashSet<string> element)
+    {
+        return ToAttributeValue(element);
+    }
+
+    AttributeValue IReferenceTypeConverter<IReadOnlySet<string>>.Write(IReadOnlySet<string> element)
+    {
+        return ToAttributeValue(element);
+    }
+}

src/DynamoDBGenerator/DynamoDBGenerator.csproj

@@ -4,7 +4,6 @@
         <TargetFramework>net8.0</TargetFramework>
         <Nullable>enable</Nullable>
         <IsPackable>true</IsPackable>
-        <LangVersion>10.0</LangVersion>
         <PackageVersion>0.0.0</PackageVersion>
         <Title>DynamoDBGenerator</Title>
         <Authors>Robert Andersson</Authors>

src/DynamoDBGenerator/Internal/Singleton.cs

@@ -0,0 +1,12 @@
+namespace DynamoDBGenerator.Internal;
+
+internal interface IStaticSingleton<out T> where T : new()
+{
+    private static T? _backingField;
+    internal static virtual T Singleton => _backingField ??= new T();
+}
+
+internal static class Singleton
+{
+    public static T Static<T>() where T : IStaticSingleton<T>, new() => T.Singleton;
+}

src/DynamoDBGenerator/Options/AttributeValueConverters.cs

@@ -1,7 +1,9 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using DynamoDBGenerator.Converters;
 using DynamoDBGenerator.Converters.Internal;
+using DynamoDBGenerator.Internal;
 
 namespace DynamoDBGenerator.Options;
 
@@ -115,5 +117,24 @@ public class AttributeValueConverters
     /// The <see cref="Guid"/> converter.
     /// </summary>
     public IValueTypeConverter<Guid> GuidConverter { get; protected init;} = new GuidConverter();
+    
+    /// <summary>
+    /// The <see cref="ISet{T}"/> converter for <see cref="string"/> sets.
+    /// </summary>
+    public IReferenceTypeConverter<ISet<string>> ISetConverter { get; protected init; } = Singleton.Static<StringSetConverter>();
+
+    /// <summary>
+    /// The <see cref="IReadOnlySet{T}"/> converter for <see cref="string"/> sets.
+    /// </summary>
+    public IReferenceTypeConverter<IReadOnlySet<string>> IReadOnlySetConverter { get; protected init; } = Singleton.Static<StringSetConverter>();
 
+    /// <summary>
+    /// The <see cref="HashSet{T}"/> converter for <see cref="string"/> sets.
+    /// </summary>
+    public IReferenceTypeConverter<HashSet<string>> HashSetConverter { get; protected init; } = Singleton.Static<StringSetConverter>();
+
+    /// <summary>
+    /// The <see cref="SortedSet{T}"/> converter for <see cref="string"/> sets.
+    /// </summary>
+    public IReferenceTypeConverter<SortedSet<string>> SortedSetConverter { get; protected init; } = Singleton.Static<StringSetConverter>();
 }