Category: .NET Core

RSCG – Microsoft.Extensions.Options.Generators.OptionsValidatorGenerator

name	Microsoft.Extensions.Options.Generators.OptionsValidatorGenerator
nuget	https://www.nuget.org/packages/Microsoft.Extensions.Options
link	https://learn.microsoft.com/en-us/dotnet/core/extensions/options-validation-generator
author	Microsoft

Generating the validation for data annotations on options classes.

This is how you can use Microsoft.Extensions.Options.Generators.OptionsValidatorGenerator .

The code that you start with is

  <Project Sdk="Microsoft.NET.Sdk">    <PropertyGroup>     <TargetFramework>net8.0</TargetFramework>     <ImplicitUsings>enable</ImplicitUsings>     <Nullable>enable</Nullable>   </PropertyGroup> 	<ItemGroup> 		<PackageReference Include="Microsoft.Extensions.Options" Version="8.0.0" /> 	</ItemGroup> 	<PropertyGroup> 		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> 		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath> 	</PropertyGroup> 	 </Project>

The code that you will use is

  namespace DemoValidatorObj;  [OptionsValidator] public partial class ValidatorForMyApp     : IValidateOptions<MyAppOptions> { }  //public class SecondModelNoNamespace //{ //    [Required] //    [MinLength(5)] //    public string P4 { get; set; } = string.Empty; //}   //[OptionsValidator] //public partial class SecondValidatorNoNamespace //    : IValidateOptions<SecondModelNoNamespace> //{ //}

  namespace DemoValidatorObj;  [DebuggerDisplay("{AppDisplayName}")] public class MyAppOptions {     public const string ConfigName = "MyAppOptionsInConfig";     [Required]     [MinLength(3)]     public string AppDisplayName { get; set; } = string.Empty;      //[ValidateObjectMembers(     //    typeof(SecondValidatorNoNamespace))]     //public SecondModelNoNamespace? P2 { get; set; } }  //[OptionsValidator] //public partial class SecondValidatorNoNamespace //    : IValidateOptions<SecondModelNoNamespace> //{ //}

The code that is generated is

      // <auto-generated/>     #nullable enable     #pragma warning disable CS1591 // Compensate for https://github.com/dotnet/roslyn/issues/54103     namespace DemoValidatorObj {     partial class ValidatorForMyApp     {         /// <summary>         /// Validates a specific named options instance (or all when <paramref name="name"/> is <see langword="null" />).         /// </summary>         /// <param name="name">The name of the options instance being validated.</param>         /// <param name="options">The options instance.</param>         /// <returns>Validation result.</returns>         [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Extensions.Options.SourceGeneration", "8.0.9.3103")]         [System.Diagnostics.CodeAnalysis.UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",              Justification = "The created ValidationContext object is used in a way that never call reflection")]         public global::Microsoft.Extensions.Options.ValidateOptionsResult Validate(string? name, global::DemoValidatorObj.MyAppOptions options)         {             global::Microsoft.Extensions.Options.ValidateOptionsResultBuilder? builder = null;             var context = new global::System.ComponentModel.DataAnnotations.ValidationContext(options);             var validationResults = new global::System.Collections.Generic.List<global::System.ComponentModel.DataAnnotations.ValidationResult>();             var validationAttributes = new global::System.Collections.Generic.List<global::System.ComponentModel.DataAnnotations.ValidationAttribute>(2);              context.MemberName = "AppDisplayName";             context.DisplayName = string.IsNullOrEmpty(name) ? "MyAppOptions.AppDisplayName" : $"{name}.AppDisplayName";             validationAttributes.Add(global::__OptionValidationStaticInstances.__Attributes.A1);             validationAttributes.Add(global::__OptionValidationStaticInstances.__Attributes.A2);             if (!global::System.ComponentModel.DataAnnotations.Validator.TryValidateValue(options.AppDisplayName, context, validationResults, validationAttributes))             {                 (builder ??= new()).AddResults(validationResults);             }              return builder is null ? global::Microsoft.Extensions.Options.ValidateOptionsResult.Success : builder.Build();         }     } } namespace __OptionValidationStaticInstances {     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Extensions.Options.SourceGeneration", "8.0.9.3103")]     file static class __Attributes     {         internal static readonly global::System.ComponentModel.DataAnnotations.RequiredAttribute A1 = new global::System.ComponentModel.DataAnnotations.RequiredAttribute();          internal static readonly __OptionValidationGeneratedAttributes.__SourceGen__MinLengthAttribute A2 = new __OptionValidationGeneratedAttributes.__SourceGen__MinLengthAttribute(             (int)3);     } } namespace __OptionValidationStaticInstances {     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Extensions.Options.SourceGeneration", "8.0.9.3103")]     file static class __Validators     {     } } namespace __OptionValidationGeneratedAttributes {     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Extensions.Options.SourceGeneration", "8.0.9.3103")]     [global::System.AttributeUsage(global::System.AttributeTargets.Property | global::System.AttributeTargets.Field | global::System.AttributeTargets.Parameter, AllowMultiple = false)]     file class __SourceGen__MinLengthAttribute : global::System.ComponentModel.DataAnnotations.ValidationAttribute     {         private static string DefaultErrorMessageString => "The field {0} must be a string or array type with a minimum length of '{1}'.";          public __SourceGen__MinLengthAttribute(int length) : base(() => DefaultErrorMessageString) { Length = length; }         public int Length { get; }         public override bool IsValid(object? value)         {             if (Length < -1)             {                 throw new global::System.InvalidOperationException("MinLengthAttribute must have a Length value that is zero or greater.");             }             if (value == null)             {                 return true;             }              int length;             if (value is string stringValue)             {                 length = stringValue.Length;             }             else if (value is System.Collections.ICollection collectionValue)             {                 length = collectionValue.Count;             }             else             {                 throw new global::System.InvalidCastException($"The field of type {value.GetType()} must be a string, array, or ICollection type.");             }              return length >= Length;         }         public override string FormatErrorMessage(string name) => string.Format(global::System.Globalization.CultureInfo.CurrentCulture, ErrorMessageString, name, Length);     } }

Code and pdf at https://ignatandrei.github.io/RSCG_Examples/v2/docs/Microsoft.Extensions.Options.Generators.OptionsValidatorGenerator

RSCG – Biwen.AutoClassGen

name	Biwen.AutoClassGen
nuget	https://www.nuget.org/packages/Biwen.AutoClassGen/
link	https://github.com/vipwan/Biwen.AutoClassGen
author	vipwan

Generating properties from interface to class.

This is how you can use Biwen.AutoClassGen .

The code that you start with is

  <Project Sdk="Microsoft.NET.Sdk">    <PropertyGroup>     <OutputType>Exe</OutputType>     <TargetFramework>net8.0</TargetFramework>     <ImplicitUsings>enable</ImplicitUsings>     <Nullable>enable</Nullable>   </PropertyGroup>    <ItemGroup>     <PackageReference Include="Biwen.AutoClassGen" Version="1.0.0.6" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />     <PackageReference Include="Biwen.AutoClassGen.Attributes" Version="1.0.0" /> 	     </ItemGroup>  	<PropertyGroup> 		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> 		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath> 	</PropertyGroup> 	 </Project>

The code that you will use is

  using FromInterface;  Console.WriteLine("Hello, World!"); Person p = new(); p.FirstName = "Andrei"; p.LastName = "Ignat"; Console.WriteLine(p.FullName());

The code that is generated is

 // <auto-generated /> // author:vipwan@outlook.com 万雅虎 // issue:https://github.com/vipwan/Biwen.AutoClassGen/issues // 如果你在使用中遇到问题,请第一时间issue,谢谢! // This file is generated by Biwen.AutoClassGen.SourceGenerator using System; using System.Collections.Generic; using System.Text; using System.Threading.Tasks; using FromInterface;  #pragma warning disable namespace FromInterface {     public partial class Person : IPerson2     {         /// <inheritdoc cref = "IPerson.FirstName"/>         [System.ComponentModel.DataAnnotations.StringLengthAttribute(100)]         [System.ComponentModel.DescriptionAttribute("person first name")]         public string FirstName { get; set; }         /// <inheritdoc cref = "IPerson.LastName"/>         public string LastName { get; set; }     } } #pragma warning restore

Code and pdf at https://ignatandrei.github.io/RSCG_Examples/v2/docs/Biwen.AutoClassGen

RSCG – PrimaryParameter

name	PrimaryParameter
nuget	https://www.nuget.org/packages/FaustVX.PrimaryParameter.SG
link	https://github.com/FaustVX/PrimaryParameter
author	FaustVX

Generating properties from .NET 8 constructor parameters

This is how you can use PrimaryParameter .

The code that you start with is

  <Project Sdk="Microsoft.NET.Sdk">    <PropertyGroup>     <OutputType>Exe</OutputType>     <TargetFramework>net8.0</TargetFramework>     <ImplicitUsings>enable</ImplicitUsings>     <Nullable>enable</Nullable>   </PropertyGroup>  	<PropertyGroup> 		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> 		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath> 	</PropertyGroup>  	<ItemGroup> 	  <PackageReference Include="FaustVX.PrimaryParameter.SG" Version="1.2.0" OutputItemType="Analyzer" ReferenceOutputAssembly="false"  /> 	</ItemGroup> </Project>

The code that you will use is

  using QuickConstructorDemo;  var p = new Person("Andrei", "Ignat");  Console.WriteLine(p.FullName());

  using PrimaryParameter.SG; namespace QuickConstructorDemo; internal partial class Person([Property]string FirstName,[Field(Name ="_LastName",Scope ="public")]string? LastName=null) {     //private readonly string FirstName;     //private readonly string? LastName;          public string FullName() => $"{FirstName} {_LastName}";      }

The code that is generated is

 namespace QuickConstructorDemo {     partial class Person     {         public string FirstName { get; init; } = FirstName;     } } namespace QuickConstructorDemo {     partial class Person     {         public readonly string _LastName = LastName;     } }

 using global::System; namespace PrimaryParameter.SG {     [AttributeUsage(AttributeTargets.Parameter, Inherited = false, AllowMultiple = true)]     sealed class FieldAttribute : Attribute     {         public string Name { get; init; }         public string AssignFormat { get; init; }         public Type Type { get; init; }         public bool IsReadonly { get; init; }         public string Scope { get; init; }     } }

 using global::System; namespace PrimaryParameter.SG {     [AttributeUsage(AttributeTargets.Parameter, Inherited = false, AllowMultiple = true)]     sealed class PropertyAttribute : Attribute     {         public string Name { get; init; }         public string AssignFormat { get; init; }         public Type Type { get; init; }         public bool WithInit { get; init; }         public string Scope { get; init; }     } }

 using global::System; namespace PrimaryParameter.SG {     [AttributeUsage(AttributeTargets.Parameter, Inherited = false, AllowMultiple = true)]     sealed class RefFieldAttribute : Attribute     {         public string Name { get; init; }         public string Scope { get; init; }         public bool IsReadonlyRef { get; init; }         public bool IsRefReadonly { get; init; }     } }

Code and pdf at https://ignatandrei.github.io/RSCG_Examples/v2/docs/PrimaryParameter

RSCG – jsonConverterSourceGenerator

name	jsonConverterSourceGenerator
nuget	https://www.nuget.org/packages/Aviationexam.GeneratedJsonConverters.SourceGenerator/
link	https://github.com/aviationexam/json-converter-source-generator
author	Aviationexam

Json Polymorphic generator

This is how you can use jsonConverterSourceGenerator .

The code that you start with is


<project sdk="Microsoft.NET.Sdk">

  <propertygroup>
    <outputtype>Exe</outputtype>
    <targetframework>net7.0</targetframework>
    <implicitusings>enable</implicitusings>
    <nullable>enable</nullable>
  </propertygroup>

  <itemgroup>
  </itemgroup>
	<itemgroup>
		<packagereference privateassets="all" version="0.1.11" include="Aviationexam.GeneratedJsonConverters.SourceGenerator">
	</packagereference>
	<propertygroup>
		<emitcompilergeneratedfiles>true</emitcompilergeneratedfiles>
		<compilergeneratedfilesoutputpath>$(BaseIntermediateOutputPath)\GX</compilergeneratedfilesoutputpath>
	</propertygroup>

</itemgroup>

The code that you will use is


//https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/polymorphism?pivots=dotnet-7-0
using JsonPolymorphicGeneratorDemo;
using System.Text.Json;

Person[] persons = new Person[2];
persons[0] = new Student() { Name="Student Ignat"};

persons[1] = new Teacher() { Name = "Teacher Ignat" };
//JsonSerializerOptions opt = new ()
//{
//    WriteIndented = true
//};
//var ser = JsonSerializer.Serialize(persons, opt);

var ser = JsonSerializer.Serialize(persons, ProjectJsonSerializerContext.Default.Options);

Console.WriteLine(ser);
var p = JsonSerializer.Deserialize<person  &#91;&#93;>(ser,ProjectJsonSerializerContext.Default.Options);
if(p != null)
foreach (var item in p)
{
    Console.WriteLine(item.Data());
}


namespace JsonPolymorphicGeneratorDemo;

[Aviationexam.GeneratedJsonConverters.Attributes.JsonPolymorphic]
[Aviationexam.GeneratedJsonConverters.Attributes.JsonDerivedType(typeof(Student))]
[Aviationexam.GeneratedJsonConverters.Attributes.JsonDerivedType(typeof(Teacher))]
public abstract partial class Person
{
    
    public string? Name { get; set; }
    public abstract string Data();
}

public class Teacher : Person
{
    public override string Data()
    {
        return "Class Teacher:" + Name;
    }
}
public class Student : Person
{
    public override string Data()
    {
        return "Class Student:" + Name;
    }
}


//https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/polymorphism?pivots=dotnet-7-0
using JsonPolymorphicGeneratorDemo;
using System.Text.Json.Serialization;

[JsonSourceGenerationOptions(
    WriteIndented = true,
    PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
    GenerationMode = JsonSourceGenerationMode.Default
)]
[JsonSerializable(typeof(Person[]))]
[JsonSerializable(typeof(Person))]
[JsonSerializable(typeof(Student))]
[JsonSerializable(typeof(Teacher))]
public partial class ProjectJsonSerializerContext : JsonSerializerContext
{
    static ProjectJsonSerializerContext()
    {
        foreach (var converter in GetPolymorphicConverters())
        {
            s_defaultOptions.Converters.Add(converter);
        }
    }
}

The code that is generated is

// ReSharper disable once CheckNamespace
namespace Aviationexam.GeneratedJsonConverters.Attributes;

/// <summary>
/// When placed on an enum, indicates that generator should not report missing <see cref="EnumJsonConverterAttribute">
/// </see></summary>
[System.AttributeUsage(System.AttributeTargets.Enum, AllowMultiple = false, Inherited = false)]
internal sealed class DisableEnumJsonConverterAttribute : System.Text.Json.Serialization.JsonAttribute
{
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

using Aviationexam.GeneratedJsonConverters.Attributes;
using System;

namespace Aviationexam.GeneratedJsonConverters;

[Flags]
[DisableEnumJsonConverter]
internal enum EnumDeserializationStrategy : byte
{
    ProjectDefault = 0,
    UseBackingType = 1 &lt;&lt; 0,
    UseEnumName = 1 &lt;&lt; 1,
}

#nullable enable

namespace Aviationexam.GeneratedJsonConverters.Attributes;

/// <summary>
/// When placed on an enum, indicates that the type should be serialized using generated enum convertor.
/// </summary>
[System.AttributeUsage(System.AttributeTargets.Enum, AllowMultiple = false, Inherited = false)]
internal sealed class EnumJsonConverterAttribute : System.Text.Json.Serialization.JsonAttribute
{
    /// <summary>
    /// Configure serialization strategy
    /// </summary>
    public EnumSerializationStrategy SerializationStrategy { get; set; } = EnumSerializationStrategy.ProjectDefault;

    /// <summary>
    /// Configure deserialization strategy
    /// </summary>
    public EnumDeserializationStrategy DeserializationStrategy { get; set; } = EnumDeserializationStrategy.ProjectDefault;
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

using System;
using System.Diagnostics.CodeAnalysis;
using System.Runtime.CompilerServices;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace Aviationexam.GeneratedJsonConverters;

internal abstract class EnumJsonConvertor<t  , tbackingtype=""> : JsonConverter<t>
    where T : struct, Enum
    where TBackingType : struct
{
    protected abstract TypeCode BackingTypeTypeCode { get; }

    protected abstract EnumDeserializationStrategy DeserializationStrategy { get; }

    protected abstract EnumSerializationStrategy SerializationStrategy { get; }

    public abstract bool TryToEnum(ReadOnlySpan<byte> enumName, out T value);

    public abstract bool TryToEnum(TBackingType numericValue, out T value);

    public abstract TBackingType ToBackingType(T value);

    public abstract ReadOnlySpan<byte> ToFirstEnumName(T value);

    public override T Read(
        ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options
    )
    {
        if (
            reader.TokenType is JsonTokenType.String
            &amp;&amp; DeserializationStrategy.HasFlag(EnumDeserializationStrategy.UseEnumName)
        )
        {
            var enumName = reader.ValueSpan;

            if (TryToEnum(enumName, out var enumValue))
            {
                return enumValue;
            }

            var stringValue = Encoding.UTF8.GetString(enumName.ToArray());

            throw new JsonException($"Undefined mapping of '{stringValue}' to enum '{typeof(T).FullName}'");
        }

        if (reader.TokenType is JsonTokenType.Number)
        {
            var numericValue = ReadAsNumber(ref reader);

            if (numericValue.HasValue)
            {
                if (TryToEnum(numericValue.Value, out var enumValue))
                {
                    return enumValue;
                }

                throw new JsonException($"Undefined mapping of '{numericValue}' to enum '{{enumFullName}}'");
            }
        }

        var value = Encoding.UTF8.GetString(reader.ValueSpan.ToArray());

        throw new JsonException($"Unable to deserialize {value}('{reader.TokenType}') into {typeof(T).Name}");
    }

    public override T ReadAsPropertyName(
        ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options
    )
    {
        if (
            reader.TokenType is JsonTokenType.PropertyName
            &amp;&amp; DeserializationStrategy.HasFlag(EnumDeserializationStrategy.UseEnumName)
        )
        {
            var enumName = reader.ValueSpan;

            if (TryToEnum(enumName, out var enumValue))
            {
                return enumValue;
            }
        }

        var value = Encoding.UTF8.GetString(reader.ValueSpan.ToArray());

        if (
            reader.TokenType is JsonTokenType.PropertyName
            &amp;&amp; DeserializationStrategy.HasFlag(EnumDeserializationStrategy.UseBackingType)
        )
        {
            var numericValue = ParseAsNumber(value);

            if (numericValue.HasValue)
            {
                if (TryToEnum(numericValue.Value, out var enumValue))
                {
                    return enumValue;
                }
            }
        }

        throw new JsonException($"Unable to deserialize {value}('{reader.TokenType}') into {typeof(T).Name}");
    }

    private TBackingType? ReadAsNumber(ref Utf8JsonReader reader) =&gt; BackingTypeTypeCode switch
    {
        TypeCode.SByte =&gt; reader.GetSByte() is var numericValue ? Unsafe.As<sbyte  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Byte =&gt; reader.GetByte() is var numericValue ? Unsafe.As<byte  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int16 =&gt; reader.GetInt16() is var numericValue ? Unsafe.As<short  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt16 =&gt; reader.GetUInt16() is var numericValue ? Unsafe.As<ushort  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int32 =&gt; reader.GetInt32() is var numericValue ? Unsafe.As<int  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt32 =&gt; reader.GetUInt32() is var numericValue ? Unsafe.As<uint  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int64 =&gt; reader.GetInt64() is var numericValue ? Unsafe.As<long  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt64 =&gt; reader.GetUInt64() is var numericValue ? Unsafe.As<ulong  , tbackingtype="">(ref numericValue) : null,
        _ =&gt; throw new ArgumentOutOfRangeException(nameof(BackingTypeTypeCode), BackingTypeTypeCode, $"Unexpected TypeCode {BackingTypeTypeCode}")
    };

    private TBackingType? ParseAsNumber(
        string value
    ) =&gt; BackingTypeTypeCode switch
    {
        TypeCode.SByte =&gt; sbyte.TryParse(value, out var numericValue) ? Unsafe.As<sbyte  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Byte =&gt; byte.TryParse(value, out var numericValue) ? Unsafe.As<byte  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int16 =&gt; short.TryParse(value, out var numericValue) ? Unsafe.As<short  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt16 =&gt; ushort.TryParse(value, out var numericValue) ? Unsafe.As<ushort  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int32 =&gt; int.TryParse(value, out var numericValue) ? Unsafe.As<int  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt32 =&gt; uint.TryParse(value, out var numericValue) ? Unsafe.As<uint  , tbackingtype="">(ref numericValue) : null,
        TypeCode.Int64 =&gt; long.TryParse(value, out var numericValue) ? Unsafe.As<long  , tbackingtype="">(ref numericValue) : null,
        TypeCode.UInt64 =&gt; ulong.TryParse(value, out var numericValue) ? Unsafe.As<ulong  , tbackingtype="">(ref numericValue) : null,
        _ =&gt; throw new ArgumentOutOfRangeException(nameof(BackingTypeTypeCode), BackingTypeTypeCode, $"Unexpected TypeCode {BackingTypeTypeCode}")
    };

    public override void Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
    {
        if (SerializationStrategy is EnumSerializationStrategy.BackingType)
        {
            WriteAsBackingType(writer, value, options);
        }
        else if (SerializationStrategy is EnumSerializationStrategy.FirstEnumName)
        {
            WriteAsFirstEnumName(writer, value, options);
        }
        else
        {
            throw new ArgumentOutOfRangeException(nameof(SerializationStrategy), SerializationStrategy, "Unknown serialization strategy");
        }
    }

    public override void WriteAsPropertyName(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
    {
        if (SerializationStrategy is EnumSerializationStrategy.BackingType)
        {
            WriteAsPropertyNameAsBackingType(writer, value, options);
        }
        else if (SerializationStrategy is EnumSerializationStrategy.FirstEnumName)
        {
            WriteAsPropertyNameAsFirstEnumName(writer, value, options);
        }
        else
        {
            throw new ArgumentOutOfRangeException(nameof(SerializationStrategy), SerializationStrategy, "Unknown serialization strategy");
        }
    }

    private void WriteAsBackingType(
        Utf8JsonWriter writer,
        T value,
        [SuppressMessage("ReSharper", "UnusedParameter.Local")]
        JsonSerializerOptions options
    )
    {
        var numericValue = ToBackingType(value);

        switch (BackingTypeTypeCode)
        {
            case TypeCode.SByte:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , sbyte="">(ref numericValue));
                break;
            case TypeCode.Byte:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , byte="">(ref numericValue));
                break;
            case TypeCode.Int16:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , short="">(ref numericValue));
                break;
            case TypeCode.UInt16:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , ushort="">(ref numericValue));
                break;
            case TypeCode.Int32:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , int="">(ref numericValue));
                break;
            case TypeCode.UInt32:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , uint="">(ref numericValue));
                break;
            case TypeCode.Int64:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , long="">(ref numericValue));
                break;
            case TypeCode.UInt64:
                writer.WriteNumberValue(Unsafe.As<tbackingtype  , ulong="">(ref numericValue));
                break;
            default:
                throw new ArgumentOutOfRangeException(nameof(BackingTypeTypeCode), BackingTypeTypeCode, $"Unexpected TypeCode {BackingTypeTypeCode}");
        }
    }

    private void WriteAsPropertyNameAsBackingType(
        Utf8JsonWriter writer,
        T value,
        [SuppressMessage("ReSharper", "UnusedParameter.Local")]
        JsonSerializerOptions options
    )
    {
        var numericValue = ToBackingType(value);

        writer.WritePropertyName($"{numericValue}");
    }

    private void WriteAsFirstEnumName(
        Utf8JsonWriter writer,
        T value,
        [SuppressMessage("ReSharper", "UnusedParameter.Local")]
        JsonSerializerOptions options
    )
    {
        var enumValue = ToFirstEnumName(value);

        writer.WriteStringValue(enumValue);
    }

    private void WriteAsPropertyNameAsFirstEnumName(
        Utf8JsonWriter writer,
        T value,
        [SuppressMessage("ReSharper", "UnusedParameter.Local")]
        JsonSerializerOptions options
    )
    {
        var enumValue = ToFirstEnumName(value);

        writer.WritePropertyName(enumValue);
    }
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

using Aviationexam.GeneratedJsonConverters.Attributes;

namespace Aviationexam.GeneratedJsonConverters;

[DisableEnumJsonConverter]
internal enum EnumSerializationStrategy : byte
{
    ProjectDefault,
    BackingType,
    FirstEnumName,
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

namespace Aviationexam.GeneratedJsonConverters;

internal readonly struct DiscriminatorStruct<t> : IDiscriminatorStruct
{
    public T Value { get; init; }

    public DiscriminatorStruct(T value)
    {
        Value = value;
    }
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

namespace Aviationexam.GeneratedJsonConverters;

internal interface IDiscriminatorStruct
{
}

#nullable enable

namespace Aviationexam.GeneratedJsonConverters.Attributes;

/// <summary>
/// This is a copy of System.Text.Json.Serialization.JsonDerivedTypeAttribute.
/// It's purpose is to replace this attribute to silence System.Text.Json.Serialization.Metadata.PolymorphicTypeResolver{ThrowHelper.ThrowNotSupportedException_BaseConverterDoesNotSupportMetadata}
///
/// When placed on a type declaration, indicates that the specified subtype should be opted into polymorphic serialization.
/// </summary>
[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, AllowMultiple = true, Inherited = false)]
internal class JsonDerivedTypeAttribute : System.Text.Json.Serialization.JsonAttribute
{
    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    /// <param name="derivedType">A derived type that should be supported in polymorphic serialization of the declared based type.
    public JsonDerivedTypeAttribute(System.Type derivedType)
    {
        DerivedType = derivedType;
    }

    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    /// <param name="derivedType">A derived type that should be supported in polymorphic serialization of the declared base type.
    /// <param name="typeDiscriminator">The type discriminator identifier to be used for the serialization of the subtype.
    public JsonDerivedTypeAttribute(System.Type derivedType, string typeDiscriminator)
    {
        DerivedType = derivedType;
        TypeDiscriminator = typeDiscriminator;
    }

    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    /// <param name="derivedType">A derived type that should be supported in polymorphic serialization of the declared base type.
    /// <param name="typeDiscriminator">The type discriminator identifier to be used for the serialization of the subtype.
    public JsonDerivedTypeAttribute(System.Type derivedType, int typeDiscriminator)
    {
        DerivedType = derivedType;
        TypeDiscriminator = typeDiscriminator;
    }

    /// <summary>
    /// A derived type that should be supported in polymorphic serialization of the declared base type.
    /// </summary>
    public System.Type DerivedType { get; }

    /// <summary>
    /// The type discriminator identifier to be used for the serialization of the subtype.
    /// </summary>
    public object? TypeDiscriminator { get; }
}

[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, AllowMultiple = true, Inherited = false)]
internal class JsonDerivedTypeAttribute<tderivedtype> : JsonDerivedTypeAttribute
{
    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    public JsonDerivedTypeAttribute() : base(typeof(TDerivedType))
    {
    }

    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    /// <param name="typeDiscriminator">The type discriminator identifier to be used for the serialization of the subtype.
    public JsonDerivedTypeAttribute(string typeDiscriminator) : base(typeof(TDerivedType), typeDiscriminator)
    {
    }

    /// <summary>
    /// Initializes a new attribute with specified parameters.
    /// </summary>
    /// <param name="typeDiscriminator">The type discriminator identifier to be used for the serialization of the subtype.
    public JsonDerivedTypeAttribute(int typeDiscriminator) : base(typeof(TDerivedType), typeDiscriminator)
    {
    }
}

#nullable enable

namespace Aviationexam.GeneratedJsonConverters.Attributes;

/// <summary>
/// This is a copy of System.Text.Json.Serialization.JsonPolymorphicAttribute.
/// It's purpose is to replace this attribute to silence System.Text.Json.Serialization.Metadata.PolymorphicTypeResolver{ThrowHelper.ThrowNotSupportedException_BaseConverterDoesNotSupportMetadata}
///
/// When placed on a type, indicates that the type should be serialized polymorphically.
/// </summary>
[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Interface, AllowMultiple = false, Inherited = false)]
internal sealed class JsonPolymorphicAttribute : System.Text.Json.Serialization.JsonAttribute
{
    /// <summary>
    /// Gets or sets a custom type discriminator property name for the polymorhic type.
    /// Uses the default '$type' property name if left unset.
    /// </summary>
    public string? TypeDiscriminatorPropertyName { get; set; }

    /// <summary>
    /// Gets or sets the behavior when serializing an undeclared derived runtime type.
    /// </summary>
    public System.Text.Json.Serialization.JsonUnknownDerivedTypeHandling UnknownDerivedTypeHandling { get; set; }

    /// <summary>
    /// When set to <see langword="true">, instructs the deserializer to ignore any
    /// unrecognized type discriminator id's and reverts to the contract of the base type.
    /// Otherwise, it will fail the deserialization.
    /// </see></summary>
    public bool IgnoreUnrecognizedTypeDiscriminators { get; set; }
}

#nullable enable

namespace PolymorphicGlobalNamespace;

internal class PersonJsonPolymorphicConverter : Aviationexam.GeneratedJsonConverters.PolymorphicJsonConvertor<global::jsonpolymorphicgeneratordemo.person>
{
    protected override System.ReadOnlySpan<byte> GetDiscriminatorPropertyName() =&gt; "$type"u8;

    protected override System.Type GetTypeForDiscriminator(
        Aviationexam.GeneratedJsonConverters.IDiscriminatorStruct discriminator
    ) =&gt; discriminator switch
    {
        Aviationexam.GeneratedJsonConverters.DiscriminatorStruct<string> { Value: "Student" } =&gt; typeof(JsonPolymorphicGeneratorDemo.Student),
        Aviationexam.GeneratedJsonConverters.DiscriminatorStruct<string> { Value: "Teacher" } =&gt; typeof(JsonPolymorphicGeneratorDemo.Teacher),

        _ =&gt; throw new System.ArgumentOutOfRangeException(nameof(discriminator), discriminator, null),
    };

    protected override Aviationexam.GeneratedJsonConverters.IDiscriminatorStruct GetDiscriminatorForType(
        System.Type type
    )
    {
        if (type == typeof(JsonPolymorphicGeneratorDemo.Student))
        {
            return new Aviationexam.GeneratedJsonConverters.DiscriminatorStruct<string>("Student");
        }
        if (type == typeof(JsonPolymorphicGeneratorDemo.Teacher))
        {
            return new Aviationexam.GeneratedJsonConverters.DiscriminatorStruct<string>("Teacher");
        }

        throw new System.ArgumentOutOfRangeException(nameof(type), type, null);
    }
}

// ReSharper disable once RedundantNullableDirective

#nullable enable

using System;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace Aviationexam.GeneratedJsonConverters;

internal abstract class PolymorphicJsonConvertor<t> : JsonConverter<t> where T : class
{
    private readonly Type _polymorphicType = typeof(T);

    protected abstract ReadOnlySpan<byte> GetDiscriminatorPropertyName();

    protected abstract Type GetTypeForDiscriminator(IDiscriminatorStruct discriminator);

    protected abstract IDiscriminatorStruct GetDiscriminatorForType(Type type);

    public override T? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
    {
        using var jsonDocument = JsonDocument.ParseValue(ref reader);

        var discriminatorPropertyName = GetDiscriminatorPropertyName();

        var discriminatorProperty = jsonDocument.RootElement
            .GetProperty(discriminatorPropertyName);

        IDiscriminatorStruct? typeDiscriminator = null;
        if (discriminatorProperty.ValueKind is JsonValueKind.String)
        {
            typeDiscriminator = new DiscriminatorStruct<string>(discriminatorProperty.GetString()!);
        }
        else if (discriminatorProperty.ValueKind is JsonValueKind.Number)
        {
            typeDiscriminator = new DiscriminatorStruct<int>(discriminatorProperty.GetInt32());
        }

        if (typeDiscriminator is null)
        {
            var discriminatorPropertyNameString = Encoding.UTF8.GetString(discriminatorPropertyName.ToArray());

            throw new JsonException($"Not found discriminator property '{discriminatorPropertyNameString}' for type {_polymorphicType}");
        }

        var type = GetTypeForDiscriminator(typeDiscriminator);

        return (T?) jsonDocument.Deserialize(type, options);
    }

    public override void Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
    {
        var instanceType = value.GetType();

        writer.WriteStartObject();

        var discriminatorPropertyName = GetDiscriminatorPropertyName();
        var discriminatorValue = GetDiscriminatorForType(instanceType);

        if (discriminatorValue is DiscriminatorStruct<string> discriminatorString)
        {
            writer.WriteString(discriminatorPropertyName, discriminatorString.Value);
        }
        else if (discriminatorValue is DiscriminatorStruct<int> discriminatorInt)
        {
            writer.WriteNumber(discriminatorPropertyName, discriminatorInt.Value);
        }

        var typeInfo = options.GetTypeInfo(instanceType);

        foreach (var p in typeInfo.Properties)
        {
            if (p.Get is null)
            {
                continue;
            }

            writer.WritePropertyName(p.Name);
            JsonSerializer.Serialize(writer, p.Get(value), p.PropertyType, options);
        }

        writer.WriteEndObject();
    }
}

#nullable enable

public partial class ProjectJsonSerializerContext
{
    public static System.Collections.Generic.IReadOnlyCollection<system.text.json.serialization.jsonconverter> GetPolymorphicConverters() =&gt; new System.Text.Json.Serialization.JsonConverter[]
    {
        new PolymorphicGlobalNamespace.PersonJsonPolymorphicConverter(),
    };

    public static void UsePolymorphicConverters(
        System.Collections.Generic.ICollection<system.text.json.serialization.jsonconverter> optionsConverters
    )
    {
        foreach (var converter in GetPolymorphicConverters())
        {
            optionsConverters.Add(converter);
        }
    }
}

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Text.Json.SourceGeneration", "7.0.9.1816")]
    public partial class ProjectJsonSerializerContext
    {
        
        private static global::System.Text.Json.JsonSerializerOptions s_defaultOptions { get; } = new global::System.Text.Json.JsonSerializerOptions()
        {
            DefaultIgnoreCondition = global::System.Text.Json.Serialization.JsonIgnoreCondition.Never,
            IgnoreReadOnlyFields = false,
            IgnoreReadOnlyProperties = false,
            IncludeFields = false,
            WriteIndented = true,
                    PropertyNamingPolicy = global::System.Text.Json.JsonNamingPolicy.CamelCase
        };
        
        private static global::ProjectJsonSerializerContext? s_defaultContext;
        
        /// <summary>
        /// The default <see cref="global::System.Text.Json.Serialization.JsonSerializerContext"> associated with a default <see cref="global::System.Text.Json.JsonSerializerOptions"> instance.
        /// </see></see></summary>
        public static global::ProjectJsonSerializerContext Default =&gt; s_defaultContext ??= new global::ProjectJsonSerializerContext(new global::System.Text.Json.JsonSerializerOptions(s_defaultOptions));
        
        /// <summary>
        /// The source-generated options associated with this context.
        /// </summary>
        protected override global::System.Text.Json.JsonSerializerOptions? GeneratedSerializerOptions { get; } = s_defaultOptions;
        
        /// <inheritdoc>
        public ProjectJsonSerializerContext() : base(null)
        {
        }
        
        /// <inheritdoc>
        public ProjectJsonSerializerContext(global::System.Text.Json.JsonSerializerOptions options) : base(options)
        {
        }
        
        private static global::System.Text.Json.Serialization.JsonConverter? GetRuntimeProvidedCustomConverter(global::System.Text.Json.JsonSerializerOptions options, global::System.Type type)
        {
            global::System.Collections.Generic.IList<global::system.text.json.serialization.jsonconverter> converters = options.Converters;
        
            for (int i = 0; i &lt; converters.Count; i++)
            {
                global::System.Text.Json.Serialization.JsonConverter? converter = converters[i];
        
                if (converter.CanConvert(type))
                {
                    if (converter is global::System.Text.Json.Serialization.JsonConverterFactory factory)
                    {
                        converter = factory.CreateConverter(type, options);
                        if (converter == null || converter is global::System.Text.Json.Serialization.JsonConverterFactory)
                        {
                            throw new global::System.InvalidOperationException(string.Format("The converter '{0}' cannot return null or a JsonConverterFactory instance.", factory.GetType()));
                        }
                    }
        
                    return converter;
                }
            }
        
            return null;
        }
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext: global::System.Text.Json.Serialization.Metadata.IJsonTypeInfoResolver
    {
        /// <inheritdoc>
        public override global::System.Text.Json.Serialization.Metadata.JsonTypeInfo GetTypeInfo(global::System.Type type)
        {
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Person[]))
            {
                return this.PersonArray;
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Person))
            {
                return this.Person;
            }
        
            if (type == typeof(global::System.String))
            {
                return this.String;
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Student))
            {
                return this.Student;
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Teacher))
            {
                return this.Teacher;
            }
        
            return null!;
        }
        
        global::System.Text.Json.Serialization.Metadata.JsonTypeInfo? global::System.Text.Json.Serialization.Metadata.IJsonTypeInfoResolver.GetTypeInfo(global::System.Type type, global::System.Text.Json.JsonSerializerOptions options)
        {
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Person[]))
            {
                return Create_PersonArray(options, makeReadOnly: false);
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Person))
            {
                return Create_Person(options, makeReadOnly: false);
            }
        
            if (type == typeof(global::System.String))
            {
                return Create_String(options, makeReadOnly: false);
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Student))
            {
                return Create_Student(options, makeReadOnly: false);
            }
        
            if (type == typeof(global::JsonPolymorphicGeneratorDemo.Teacher))
            {
                return Create_Teacher(options, makeReadOnly: false);
            }
        
            return null;
        }
        
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person>? _Person;
        /// <summary>
        /// Defines the source generated JSON serialization contract metadata for a given type.
        /// </summary>
        public global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person> Person
        {
            get =&gt; _Person ??= Create_Person(Options, makeReadOnly: true);
        }
        
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person> Create_Person(global::System.Text.Json.JsonSerializerOptions options, bool makeReadOnly)
        {
            global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person>? jsonTypeInfo = null;
            global::System.Text.Json.Serialization.JsonConverter? customConverter;
            if (options.Converters.Count &gt; 0 &amp;&amp; (customConverter = GetRuntimeProvidedCustomConverter(options, typeof(global::JsonPolymorphicGeneratorDemo.Person))) != null)
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::jsonpolymorphicgeneratordemo.person>(options, customConverter);
            }
            else
            {
                global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.person> objectInfo = new global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.person>()
                {
                    ObjectCreator = null,
                    ObjectWithParameterizedConstructorCreator = null,
                    PropertyMetadataInitializer = _ =&gt; PersonPropInit(options),
                    ConstructorParameterMetadataInitializer = null,
                    NumberHandling = default,
                    SerializeHandler = PersonSerializeHandler
                };
        
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateObjectInfo<global::jsonpolymorphicgeneratordemo.person>(options, objectInfo);
            }
        
            if (makeReadOnly)
            {
                jsonTypeInfo.MakeReadOnly();
            }
        
            return jsonTypeInfo;
        }
        
        private static global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] PersonPropInit(global::System.Text.Json.JsonSerializerOptions options)
        {
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] properties = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[1];
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string> info0 = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string>()
            {
                IsProperty = true,
                IsPublic = true,
                IsVirtual = false,
                DeclaringType = typeof(global::JsonPolymorphicGeneratorDemo.Person),
                Converter = null,
                Getter = static (obj) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name!,
                Setter = static (obj, value) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name = value!,
                IgnoreCondition = null,
                HasJsonInclude = false,
                IsExtensionData = false,
                NumberHandling = default,
                PropertyName = "Name",
                JsonPropertyName = null
            };
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo propertyInfo0 = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreatePropertyInfo<global::system.string>(options, info0);
            properties[0] = propertyInfo0;
        
            return properties;
        }
        
        // Intentionally not a static method because we create a delegate to it. Invoking delegates to instance
        // methods is almost as fast as virtual calls. Static methods need to go through a shuffle thunk.
        private void PersonSerializeHandler(global::System.Text.Json.Utf8JsonWriter writer, global::JsonPolymorphicGeneratorDemo.Person? value)
        {
            if (value == null)
            {
                writer.WriteNullValue();
                return;
            }
        
            writer.WriteStartObject();
            writer.WriteString(PropName_name, value.Name);
        
            writer.WriteEndObject();
        }
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;>? _PersonArray;
        /// <summary>
        /// Defines the source generated JSON serialization contract metadata for a given type.
        /// </summary>
        public global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;> PersonArray
        {
            get =&gt; _PersonArray ??= Create_PersonArray(Options, makeReadOnly: true);
        }
        
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;> Create_PersonArray(global::System.Text.Json.JsonSerializerOptions options, bool makeReadOnly)
        {
            global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;>? jsonTypeInfo = null;
            global::System.Text.Json.Serialization.JsonConverter? customConverter;
            if (options.Converters.Count &gt; 0 &amp;&amp; (customConverter = GetRuntimeProvidedCustomConverter(options, typeof(global::JsonPolymorphicGeneratorDemo.Person[]))) != null)
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;>(options, customConverter);
            }
            else
            {
                global::System.Text.Json.Serialization.Metadata.JsonCollectionInfoValues<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;> info = new global::System.Text.Json.Serialization.Metadata.JsonCollectionInfoValues<global::jsonpolymorphicgeneratordemo.person  &#91;&#93;>()
                {
                    ObjectCreator = null,
                    NumberHandling = default,
                    SerializeHandler = PersonArraySerializeHandler
                };
        
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateArrayInfo<global::jsonpolymorphicgeneratordemo.person>(options, info);
        
            }
        
            if (makeReadOnly)
            {
                jsonTypeInfo.MakeReadOnly();
            }
        
            return jsonTypeInfo;
        }
        
        
        // Intentionally not a static method because we create a delegate to it. Invoking delegates to instance
        // methods is almost as fast as virtual calls. Static methods need to go through a shuffle thunk.
        private void PersonArraySerializeHandler(global::System.Text.Json.Utf8JsonWriter writer, global::JsonPolymorphicGeneratorDemo.Person[]? value)
        {
            if (value == null)
            {
                writer.WriteNullValue();
                return;
            }
        
            writer.WriteStartArray();
        
            for (int i = 0; i &lt; value.Length; i++)
            {
                PersonSerializeHandler(writer, value[i]!);
            }
        
            writer.WriteEndArray();
        }
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        
        private static readonly global::System.Text.Json.JsonEncodedText PropName_name = global::System.Text.Json.JsonEncodedText.Encode("name");
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::system.string>? _String;
        /// <summary>
        /// Defines the source generated JSON serialization contract metadata for a given type.
        /// </summary>
        public global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::system.string> String
        {
            get =&gt; _String ??= Create_String(Options, makeReadOnly: true);
        }
        
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::system.string> Create_String(global::System.Text.Json.JsonSerializerOptions options, bool makeReadOnly)
        {
            global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::system.string>? jsonTypeInfo = null;
            global::System.Text.Json.Serialization.JsonConverter? customConverter;
            if (options.Converters.Count &gt; 0 &amp;&amp; (customConverter = GetRuntimeProvidedCustomConverter(options, typeof(global::System.String))) != null)
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::system.string>(options, customConverter);
            }
            else
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::system.string>(options, global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.StringConverter);
            }
        
            if (makeReadOnly)
            {
                jsonTypeInfo.MakeReadOnly();
            }
        
            return jsonTypeInfo;
        }
        
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.student>? _Student;
        /// <summary>
        /// Defines the source generated JSON serialization contract metadata for a given type.
        /// </summary>
        public global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.student> Student
        {
            get =&gt; _Student ??= Create_Student(Options, makeReadOnly: true);
        }
        
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.student> Create_Student(global::System.Text.Json.JsonSerializerOptions options, bool makeReadOnly)
        {
            global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.student>? jsonTypeInfo = null;
            global::System.Text.Json.Serialization.JsonConverter? customConverter;
            if (options.Converters.Count &gt; 0 &amp;&amp; (customConverter = GetRuntimeProvidedCustomConverter(options, typeof(global::JsonPolymorphicGeneratorDemo.Student))) != null)
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::jsonpolymorphicgeneratordemo.student>(options, customConverter);
            }
            else
            {
                global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.student> objectInfo = new global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.student>()
                {
                    ObjectCreator = static () =&gt; new global::JsonPolymorphicGeneratorDemo.Student(),
                    ObjectWithParameterizedConstructorCreator = null,
                    PropertyMetadataInitializer = _ =&gt; StudentPropInit(options),
                    ConstructorParameterMetadataInitializer = null,
                    NumberHandling = default,
                    SerializeHandler = StudentSerializeHandler
                };
        
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateObjectInfo<global::jsonpolymorphicgeneratordemo.student>(options, objectInfo);
            }
        
            if (makeReadOnly)
            {
                jsonTypeInfo.MakeReadOnly();
            }
        
            return jsonTypeInfo;
        }
        
        private static global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] StudentPropInit(global::System.Text.Json.JsonSerializerOptions options)
        {
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] properties = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[1];
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string> info0 = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string>()
            {
                IsProperty = true,
                IsPublic = true,
                IsVirtual = false,
                DeclaringType = typeof(global::JsonPolymorphicGeneratorDemo.Person),
                Converter = null,
                Getter = static (obj) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name!,
                Setter = static (obj, value) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name = value!,
                IgnoreCondition = null,
                HasJsonInclude = false,
                IsExtensionData = false,
                NumberHandling = default,
                PropertyName = "Name",
                JsonPropertyName = null
            };
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo propertyInfo0 = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreatePropertyInfo<global::system.string>(options, info0);
            properties[0] = propertyInfo0;
        
            return properties;
        }
        
        // Intentionally not a static method because we create a delegate to it. Invoking delegates to instance
        // methods is almost as fast as virtual calls. Static methods need to go through a shuffle thunk.
        private void StudentSerializeHandler(global::System.Text.Json.Utf8JsonWriter writer, global::JsonPolymorphicGeneratorDemo.Student? value)
        {
            if (value == null)
            {
                writer.WriteNullValue();
                return;
            }
        
            writer.WriteStartObject();
            writer.WriteString(PropName_name, value.Name);
        
            writer.WriteEndObject();
        }
    }

// <auto-generated>

#nullable enable annotations
#nullable disable warnings

// Suppress warnings about [Obsolete] member usage in generated code.
#pragma warning disable CS0618
    public partial class ProjectJsonSerializerContext
    {
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.teacher>? _Teacher;
        /// <summary>
        /// Defines the source generated JSON serialization contract metadata for a given type.
        /// </summary>
        public global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.teacher> Teacher
        {
            get =&gt; _Teacher ??= Create_Teacher(Options, makeReadOnly: true);
        }
        
        private global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.teacher> Create_Teacher(global::System.Text.Json.JsonSerializerOptions options, bool makeReadOnly)
        {
            global::System.Text.Json.Serialization.Metadata.JsonTypeInfo<global::jsonpolymorphicgeneratordemo.teacher>? jsonTypeInfo = null;
            global::System.Text.Json.Serialization.JsonConverter? customConverter;
            if (options.Converters.Count &gt; 0 &amp;&amp; (customConverter = GetRuntimeProvidedCustomConverter(options, typeof(global::JsonPolymorphicGeneratorDemo.Teacher))) != null)
            {
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateValueInfo<global::jsonpolymorphicgeneratordemo.teacher>(options, customConverter);
            }
            else
            {
                global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.teacher> objectInfo = new global::System.Text.Json.Serialization.Metadata.JsonObjectInfoValues<global::jsonpolymorphicgeneratordemo.teacher>()
                {
                    ObjectCreator = static () =&gt; new global::JsonPolymorphicGeneratorDemo.Teacher(),
                    ObjectWithParameterizedConstructorCreator = null,
                    PropertyMetadataInitializer = _ =&gt; TeacherPropInit(options),
                    ConstructorParameterMetadataInitializer = null,
                    NumberHandling = default,
                    SerializeHandler = TeacherSerializeHandler
                };
        
                jsonTypeInfo = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreateObjectInfo<global::jsonpolymorphicgeneratordemo.teacher>(options, objectInfo);
            }
        
            if (makeReadOnly)
            {
                jsonTypeInfo.MakeReadOnly();
            }
        
            return jsonTypeInfo;
        }
        
        private static global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] TeacherPropInit(global::System.Text.Json.JsonSerializerOptions options)
        {
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[] properties = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo[1];
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string> info0 = new global::System.Text.Json.Serialization.Metadata.JsonPropertyInfoValues<global::system.string>()
            {
                IsProperty = true,
                IsPublic = true,
                IsVirtual = false,
                DeclaringType = typeof(global::JsonPolymorphicGeneratorDemo.Person),
                Converter = null,
                Getter = static (obj) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name!,
                Setter = static (obj, value) =&gt; ((global::JsonPolymorphicGeneratorDemo.Person)obj).Name = value!,
                IgnoreCondition = null,
                HasJsonInclude = false,
                IsExtensionData = false,
                NumberHandling = default,
                PropertyName = "Name",
                JsonPropertyName = null
            };
        
            global::System.Text.Json.Serialization.Metadata.JsonPropertyInfo propertyInfo0 = global::System.Text.Json.Serialization.Metadata.JsonMetadataServices.CreatePropertyInfo<global::system.string>(options, info0);
            properties[0] = propertyInfo0;
        
            return properties;
        }
        
        // Intentionally not a static method because we create a delegate to it. Invoking delegates to instance
        // methods is almost as fast as virtual calls. Static methods need to go through a shuffle thunk.
        private void TeacherSerializeHandler(global::System.Text.Json.Utf8JsonWriter writer, global::JsonPolymorphicGeneratorDemo.Teacher? value)
        {
            if (value == null)
            {
                writer.WriteNullValue();
                return;
            }
        
            writer.WriteStartObject();
            writer.WriteString(PropName_name, value.Name);
        
            writer.WriteEndObject();
        }
    }

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/jsonConverterSourceGenerator

RSCG – N.SourceGenerators.UnionTypes

name	N.SourceGenerators.UnionTypes
nuget	https://www.nuget.org/packages/N.SourceGenerators.UnionTypes/
link	https://github.com/Ne4to/N.SourceGenerators.UnionTypes
author	Alexey Sosnin

Generating different union types

This is how you can use N.SourceGenerators.UnionTypes .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net7.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="N.SourceGenerators.UnionTypes" Version="0.26.0" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is


using UnionTypesDemo;

Console.WriteLine("Save or not");
var data = SaveToDatabase.Save(0);
Console.WriteLine(data.IsValidationError);
data = SaveToDatabase.Save(1);
Console.WriteLine(data.IsSuccess);


using N.SourceGenerators.UnionTypes;
namespace UnionTypesDemo;
public record Success(int Value);
public record ValidationError(string Message);

[UnionType(typeof(Success))]
[UnionType(typeof(ValidationError))]
public partial class ResultSave
{
}


namespace UnionTypesDemo;

public class SaveToDatabase
{
    public static ResultSave Save(int i)
    {
        if(i ==0)
        {
            return new ValidationError(" cannot save 0");
        }
        return new Success(i);
    }
}

The code that is generated is

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.GenericParameter, Inherited = false, AllowMultiple = false)]
    internal sealed class GenericUnionTypeAttribute : Attribute
    {
        public string? Alias { get; set; }
        public bool AllowNull { get; set; }
        public object? TypeDiscriminator { get; set; }
    }
}

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct, Inherited = false, AllowMultiple = false)]
    internal sealed class JsonPolymorphicUnionAttribute : Attribute
    {
        public string? TypeDiscriminatorPropertyName { get; set; }
    }
}

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#pragma warning disable
#nullable enable
namespace UnionTypesDemo
{
    partial class ResultSave : System.IEquatable<ResultSave>
    {
        private readonly int _variantId;
        private const int SuccessId = 1;
        private readonly global::UnionTypesDemo.Success _success;
        public bool IsSuccess => _variantId == SuccessId;

        public global::UnionTypesDemo.Success AsSuccess
        {
            get
            {
                if (_variantId == SuccessId)
                    return _success;
                throw new System.InvalidOperationException($"Unable convert to Success. Inner value is {ValueAlias} not Success.");
            }
        }

        public ResultSave(global::UnionTypesDemo.Success success)
        {
            System.ArgumentNullException.ThrowIfNull(success);
            _variantId = SuccessId;
            _success = success;
        }

        public static implicit operator ResultSave(global::UnionTypesDemo.Success success) => new ResultSave(success);
        public static explicit operator global::UnionTypesDemo.Success(ResultSave value)
        {
            if (value._variantId == SuccessId)
                return value._success;
            throw new System.InvalidOperationException($"Unable convert to Success. Inner value is {value.ValueAlias} not Success.");
        }

        public bool TryGetSuccess([System.Diagnostics.CodeAnalysis.NotNullWhen(true)] out global::UnionTypesDemo.Success value)
        {
            if (_variantId == SuccessId)
            {
                value = _success;
                return true;
            }
            else
            {
                value = default;
                return false;
            }
        }

        private const int ValidationErrorId = 2;
        private readonly global::UnionTypesDemo.ValidationError _validationError;
        public bool IsValidationError => _variantId == ValidationErrorId;

        public global::UnionTypesDemo.ValidationError AsValidationError
        {
            get
            {
                if (_variantId == ValidationErrorId)
                    return _validationError;
                throw new System.InvalidOperationException($"Unable convert to ValidationError. Inner value is {ValueAlias} not ValidationError.");
            }
        }

        public ResultSave(global::UnionTypesDemo.ValidationError validationError)
        {
            System.ArgumentNullException.ThrowIfNull(validationError);
            _variantId = ValidationErrorId;
            _validationError = validationError;
        }

        public static implicit operator ResultSave(global::UnionTypesDemo.ValidationError validationError) => new ResultSave(validationError);
        public static explicit operator global::UnionTypesDemo.ValidationError(ResultSave value)
        {
            if (value._variantId == ValidationErrorId)
                return value._validationError;
            throw new System.InvalidOperationException($"Unable convert to ValidationError. Inner value is {value.ValueAlias} not ValidationError.");
        }

        public bool TryGetValidationError([System.Diagnostics.CodeAnalysis.NotNullWhen(true)] out global::UnionTypesDemo.ValidationError value)
        {
            if (_variantId == ValidationErrorId)
            {
                value = _validationError;
                return true;
            }
            else
            {
                value = default;
                return false;
            }
        }

        public TOut Match<TOut>(global::System.Func<global::UnionTypesDemo.Success, TOut> matchSuccess, global::System.Func<global::UnionTypesDemo.ValidationError, TOut> matchValidationError)
        {
            if (_variantId == SuccessId)
                return matchSuccess(_success);
            if (_variantId == ValidationErrorId)
                return matchValidationError(_validationError);
            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public async global::System.Threading.Tasks.Task<TOut> MatchAsync<TOut>(global::System.Func<global::UnionTypesDemo.Success, global::System.Threading.CancellationToken, global::System.Threading.Tasks.Task<TOut>> matchSuccess, global::System.Func<global::UnionTypesDemo.ValidationError, global::System.Threading.CancellationToken, global::System.Threading.Tasks.Task<TOut>> matchValidationError, global::System.Threading.CancellationToken ct)
        {
            if (_variantId == SuccessId)
                return await matchSuccess(_success, ct).ConfigureAwait(false);
            if (_variantId == ValidationErrorId)
                return await matchValidationError(_validationError, ct).ConfigureAwait(false);
            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public void Switch(global::System.Action<global::UnionTypesDemo.Success> switchSuccess, global::System.Action<global::UnionTypesDemo.ValidationError> switchValidationError)
        {
            if (_variantId == SuccessId)
            {
                switchSuccess(_success);
                return;
            }

            if (_variantId == ValidationErrorId)
            {
                switchValidationError(_validationError);
                return;
            }

            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public async global::System.Threading.Tasks.Task SwitchAsync(global::System.Func<global::UnionTypesDemo.Success, global::System.Threading.CancellationToken, global::System.Threading.Tasks.Task> switchSuccess, global::System.Func<global::UnionTypesDemo.ValidationError, global::System.Threading.CancellationToken, global::System.Threading.Tasks.Task> switchValidationError, global::System.Threading.CancellationToken ct)
        {
            if (_variantId == SuccessId)
            {
                await switchSuccess(_success, ct).ConfigureAwait(false);
                return;
            }

            if (_variantId == ValidationErrorId)
            {
                await switchValidationError(_validationError, ct).ConfigureAwait(false);
                return;
            }

            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public global::System.Type ValueType
        {
            get
            {
                if (_variantId == SuccessId)
                    return typeof(global::UnionTypesDemo.Success);
                if (_variantId == ValidationErrorId)
                    return typeof(global::UnionTypesDemo.ValidationError);
                throw new System.InvalidOperationException("Inner type is unknown");
            }
        }

        private string ValueAlias
        {
            get
            {
                if (_variantId == SuccessId)
                    return "Success";
                if (_variantId == ValidationErrorId)
                    return "ValidationError";
                throw new System.InvalidOperationException("Inner type is unknown");
            }
        }

        public override int GetHashCode()
        {
            if (_variantId == SuccessId)
                return _success.GetHashCode();
            if (_variantId == ValidationErrorId)
                return _validationError.GetHashCode();
            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public static bool operator ==(ResultSave? left, ResultSave? right)
        {
            return Equals(left, right);
        }

        public static bool operator !=(ResultSave? left, ResultSave? right)
        {
            return !Equals(left, right);
        }

        public bool Equals(ResultSave? other)
        {
            if (ReferenceEquals(null, other))
            {
                return false;
            }

            if (ReferenceEquals(this, other))
            {
                return true;
            }

            if (ValueType != other.ValueType)
            {
                return false;
            }

            if (_variantId == SuccessId)
                return System.Collections.Generic.EqualityComparer<global::UnionTypesDemo.Success>.Default.Equals(_success, other._success);
            if (_variantId == ValidationErrorId)
                return System.Collections.Generic.EqualityComparer<global::UnionTypesDemo.ValidationError>.Default.Equals(_validationError, other._validationError);
            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public override string ToString()
        {
            if (_variantId == SuccessId)
                return _success.ToString();
            if (_variantId == ValidationErrorId)
                return _validationError.ToString();
            throw new System.InvalidOperationException("Inner type is unknown");
        }

        public override bool Equals(object? other)
        {
            if (ReferenceEquals(null, other))
            {
                return false;
            }

            if (ReferenceEquals(this, other))
            {
                return true;
            }

            if (other.GetType() != typeof(ResultSave))
            {
                return false;
            }

            return Equals((ResultSave)other);
        }
    }
}

#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.Class, Inherited = false, AllowMultiple = true)]
    sealed class UnionConverterAttribute : Attribute
    {
        public Type FromType { get; }
        public Type ToType { get; }
        public string? MethodName { get; }

        public UnionConverterAttribute(Type fromType, Type toType, string? methodName = null)
        {
            FromType = fromType;
            ToType = toType;
            MethodName = methodName;
        }
    }
}

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct, Inherited = false, AllowMultiple = true)]
    sealed class UnionConverterFromAttribute : Attribute
    {
        public Type FromType { get; }

        public UnionConverterFromAttribute(Type fromType)
        {
            FromType = fromType;
        }
    }
}

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct, Inherited = false, AllowMultiple = true)]
    sealed class UnionConverterToAttribute : Attribute
    {
        public Type ToType { get; }

        public UnionConverterToAttribute(Type toType)
        {
            ToType = toType;
        }
    }
}

// <auto-generated>
//   This code was generated by https://github.com/Ne4to/N.SourceGenerators.UnionTypes
//   Feel free to open an issue
// </auto-generated>
#nullable enable
using System;
using System.Runtime.CompilerServices;

namespace N.SourceGenerators.UnionTypes
{
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Struct, Inherited = false, AllowMultiple = true)]
    internal sealed class UnionTypeAttribute : Attribute
    {
        public Type Type { get; }
        public string? Alias { get; }
        public int Order { get; }
        public bool AllowNull { get; set; }
        public object? TypeDiscriminator { get; set; }

        public UnionTypeAttribute(Type type, string? alias = null, [CallerLineNumber] int order = 0)
        {
            Type = type;
            Alias = alias;
            Order = order;
        }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/N.SourceGenerators.UnionTypes

RSCG – AutoConstructor

name	AutoConstructor
nuget	https://www.nuget.org/packages/AutoConstructor/
link	https://github.com/k94ll13nn3/AutoConstructor
author	Kévin Gallienne

Generating constructor for class with many properties

This is how you can use AutoConstructor .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net7.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>

	<ItemGroup>
	  <PackageReference Include="AutoConstructor" Version="4.1.1">
	    <PrivateAssets>all</PrivateAssets>
	    <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
	  </PackageReference>
	</ItemGroup>
</Project>

The code that you will use is


using QuickConstructorDemo;

var p = new Person("Andrei", "Ignat");

Console.WriteLine(p.FullName());


namespace QuickConstructorDemo;

[AutoConstructor]
internal partial class Person
{
    private readonly string FirstName;
    private readonly string? LastName;
    
    public string FullName() => $"{FirstName} {LastName}";
    
}

The code that is generated is

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by the AutoConstructor source generator.
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

[System.AttributeUsage(System.AttributeTargets.Class, Inherited = false, AllowMultiple = false)]
internal sealed class AutoConstructorAttribute : System.Attribute
{
}

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by the AutoConstructor source generator.
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

[System.AttributeUsage(System.AttributeTargets.Field, Inherited = false, AllowMultiple = false)]
internal sealed class AutoConstructorIgnoreAttribute : System.Attribute
{
}

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by the AutoConstructor source generator.
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

[System.AttributeUsage(System.AttributeTargets.Field, Inherited = false, AllowMultiple = false)]
internal sealed class AutoConstructorInjectAttribute : System.Attribute
{
    public AutoConstructorInjectAttribute(string initializer = null, string parameterName = null, System.Type injectedType = null)
    {
        Initializer = initializer;
        ParameterName = parameterName;
        InjectedType = injectedType;
    }

    public string Initializer { get; }

    public string ParameterName { get; }

    public System.Type InjectedType { get; }
}

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by the AutoConstructor source generator.
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
#nullable enable
namespace QuickConstructorDemo
{
    partial class Person
    {
        public Person(string FirstName, string? LastName)
        {
            this.FirstName = FirstName;
            this.LastName = LastName;
        }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/AutoConstructor

RSCG – DudNet

name	DudNet
nuget	https://www.nuget.org/packages/Jwshyns.DudNet/
link	https://github.com/jwshyns/DudNet
author	jwshyns

Generate proxy classes for the principal classes

This is how you can use DudNet .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net7.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Jwshyns.DudNet" Version="1.2.0" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is


using DudNetDemo;

var p = new Person();
var p1= new PersonProxy(p);
p1.FirstName = "John";
p1.LastName = "Doe";
Console.WriteLine(p.FullName());
Console.WriteLine(p1.FullName());


using DudNet.Attributes;
using System.Runtime.CompilerServices;

namespace DudNetDemo;
[ProxyService]
public partial class Person : IPerson
{
    public string? FirstName { get; set; }
    public string? LastName { get; set; }
    public string FullName()
    {
        return FirstName + " " + LastName;
    }
}

The code that is generated is

using System.Runtime.CompilerServices;
using DudNet.Attributes;
using System.Runtime.CompilerServices;

namespace DudNetDemo;

/// <inheritdoc cref="IPerson"/>
public partial class PersonDud : IPerson {

	public string? FirstName {
		get {
			return (string?) default;
		}
		set {
		}
	}
	public string? LastName {
		get {
			return (string?) default;
		}
		set {
		}
	}
	public string FullName() {
		return (string) default;
	}

}

using System.Runtime.CompilerServices;
using DudNet.Attributes;
using System.Runtime.CompilerServices;

namespace DudNetDemo;

/// <inheritdoc cref="IPerson"/>
public partial class PersonProxy : IPerson {

	private readonly IPerson _service;

	public string? FirstName {
		get {
			Interceptor();
			get_FirstNameInterceptor();
			return _service.FirstName;
		}
		set {
			Interceptor();
			set_FirstNameInterceptor(value);
			_service.FirstName = value;
		}
	}
	public string? LastName {
		get {
			Interceptor();
			get_LastNameInterceptor();
			return _service.LastName;
		}
		set {
			Interceptor();
			set_LastNameInterceptor(value);
			_service.LastName = value;
		}
	}
	public string FullName() {
		Interceptor();
		FullNameInterceptor();
		return _service.FullName();
	}
	partial void Interceptor([CallerMemberName]string callerName = null);
	partial void get_FirstNameInterceptor();
	partial void set_FirstNameInterceptor(string? value);
	partial void get_LastNameInterceptor();
	partial void set_LastNameInterceptor(string? value);
	partial void FullNameInterceptor();

}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/DudNet

RSCG – MinimalApiBuilder

name	MinimalApiBuilder
nuget	https://www.nuget.org/packages/MinimalApiBuilder/
link	https://github.com/JensDll/MinimalApiBuilder
author

Generate Minimal API from classes

This is how you can use MinimalApiBuilder .

The code that you start with is


<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>net7.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="7.0.12" />
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
	  <PackageReference Include="MinimalApiBuilder" Version="1.3.3" />
  </ItemGroup>

	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>

</Project>

The code that you will use is


using MinimalApiBuilder;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
//MinimalApiBuilder.DependencyInjection.AddMinimalApiBuilderEndpoints(builder.Services);
builder.Services.AddMinimalApiBuilderEndpoints();
var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseAuthorization();

app.MapControllers();

app.MapGet<BasicEndpoint>("/hello");
app.Run();


using Microsoft.AspNetCore.Mvc;
using MinimalApiBuilder;

public partial class BasicEndpoint : MinimalApiBuilderEndpoint
{
    private static string Handle([FromServices] BasicEndpoint endpoint)
    {
        return "Hello, World!";
    }
}

The code that is generated is

// <auto-generated>
// This is a MinimalApiBuilder source generated file.
// </auto-generated>

#nullable enable

namespace MinimalApiBuilder
{
    public static class DependencyInjection
    {
        [global::System.CodeDom.Compiler.GeneratedCodeAttribute("MinimalApiBuilder.Generator", "1.3.3.0")]
        public static global::Microsoft.Extensions.DependencyInjection.IServiceCollection AddMinimalApiBuilderEndpoints(this global::Microsoft.Extensions.DependencyInjection.IServiceCollection services)
        {
            global::Microsoft.Extensions.DependencyInjection.ServiceCollectionServiceExtensions.AddScoped<global::BasicEndpoint>(services);
            return services;
        }
    }
}

// <auto-generated>
// This is a MinimalApiBuilder source generated file.
// </auto-generated>

#nullable enable

public partial class BasicEndpoint : global::MinimalApiBuilder.IEndpoint
{
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("MinimalApiBuilder.Generator", "1.3.3.0")]
    public static global::System.Delegate _auto_generated_Handler { get; } = Handle;
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("MinimalApiBuilder.Generator", "1.3.3.0")]
    public static void _auto_generated_Configure(global::Microsoft.AspNetCore.Builder.RouteHandlerBuilder builder)
    {
    }
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("MinimalApiBuilder.Generator", "1.3.3.0")]
    public static void Configure(global::Microsoft.AspNetCore.Builder.RouteHandlerBuilder builder)
    {
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/MinimalApiBuilder

What I have learned from 80+ RSCG

I have analyzed more than 80 Roslyn Source Code Generators – see https://ignatandrei.github.io/RSCG_Examples/v2/docs/List-of-RSCG . The conclusions are here:

RSCG is here to stay . There are examples from Microsoft – and a bunch of other RSCG
First version of RSCG was simple, but VS not performant. The second version is more difficult to implement – but VS is more happy
There are many RSCG for the same thing – for example, generating constructors from fields / properties: https://ignatandrei.github.io/RSCG_Examples/v2/docs/rscg-examples#constructor . You have to test them like you test any dll
Creating RSCG is difficult – you can add some errors to the code generated and/or warnings and/or more problems. I will put here my findings: https://ignatandrei.github.io/RSCG_Examples/v2/docs/GoodPractices

Adding more data to a result of a task

Every now and then I need to generate , from an array of data, an array of Tasks and then

await Task.WhenAll(TheTaskArray)

The problem is that I need to consolidate the return data of each array with the original array – to make some modifications.

For example, in the generator of https://ignatandrei.github.io/RSCG_Examples/v2/docs/category/rscg-examples I do something like this

var t = _AllDescriptions
            .Select(it =>GrabReadMe(it))
            .ToArray();
var data = await Task.WhenAll(t);
//now, for each item in data array I want to put something into original _AllDescriptions

My first try was a simple class

public struct TaskWithData<TData, TResult>//: INotifyCompletion
{
    private readonly TData data;
    private readonly Task<TResult> taskToExecute;
 
    public TaskWithData(TData data,Task<TResult> taskToExecute)
    {
        ArgumentNullException.ThrowIfNull(taskToExecute);
        this.data = data;
        this.taskToExecute = taskToExecute;
    }
# region add this to have Task.WhenAll
    public async Task<( TData data, TResult res)> GetTask() {
        var res = await taskToExecute;
        return (data,res);
    }
    public static explicit operator Task<(TData data, TResult res)>(TaskWithData<TData,TResult> b) 
        => b.GetTask() ;

    #endregion
}

And now the code could be written as

var t = _AllDescriptions.Select(
            it => new TaskWithData<Description, string?>(it, GrabReadMe(it))
            )
            .Select(td=>td.GetTask())            
            .ToArray();

        var desc = await Task.WhenAll(t);
        foreach (var item in desc)
        {
            item.data.Readme = item.res;
        }

But I do not like so much … so 2 iterations with extensions

public static class Extensions
{ 
    #region transform to task
    public static Task<( TData data, TResult res)> AddData<TData, TResult>(this Task<TResult> taskToExecute, TData data)
    {
        var td=new TaskWithData<TData, TResult>(data,taskToExecute);
        return td.GetTask();
    }
    public static Task<(TData data, TResult res)>[] SelectTaskWithData<TData, TResult>(this TData[] arr,Func<TData, Task<TResult>> func) {
        return arr.Select(it => func(it).AddData(it)).ToArray();
    }
    #endregion
}

So now the code becomes

var t = _AllDescriptions
            .Select(it =>GrabReadMe(it).AddData(it))
            .ToArray();

var t = _AllDescriptions.SelectTaskWithData(GrabReadMe).ToArray();

It was interesting to create this in order to add more data to the return value of a Task

Category: .NET Core

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