Added DataLoader group refinements.

src/HotChocolate/Core/src/Types.Analyzers/FileBuilders/DataLoaderFileBuilder.cs

@@ -499,6 +499,7 @@ public void WriteDataLoaderGroupClass(
 
         _writer.DecreaseIndent();
         _writer.WriteIndentedLine("}");
+        _writer.WriteLine();
 
         _writer.WriteIndentedLine("public sealed class {0} : I{0}", groupClassName);
         _writer.WriteIndentedLine("{");

src/HotChocolate/Core/src/Types.Analyzers/Helpers/DataLoaderAttributeHelper.cs

@@ -28,11 +28,15 @@ static void AddGroupNames(ImmutableHashSet<string>.Builder builder, IEnumerable<
             {
                 if (IsDataLoaderGroupAttribute(attribute.AttributeClass))
                 {
-                    foreach (var arg in attribute.ConstructorArguments.FirstOrDefault().Values)
+                    var constructorArguments = attribute.ConstructorArguments;
+                    if (constructorArguments.Length > 0)
                     {
-                        if (arg.Value is string groupName)
+                        foreach (var arg in constructorArguments[0].Values)
                         {
-                            builder.Add(groupName);
+                            if (arg.Value is string groupName)
+                            {
+                                builder.Add(groupName);
+                            }
                         }
                     }
                 }

src/HotChocolate/Core/src/Types.Analyzers/Models/DataLoaderInfo.cs

@@ -258,7 +258,8 @@ public override bool Equals(SyntaxInfo obj)
 
     private bool Equals(DataLoaderInfo other)
         => AttributeSyntax.IsEquivalentTo(other.AttributeSyntax)
-            && MethodSyntax.IsEquivalentTo(other.MethodSyntax);
+            && MethodSyntax.IsEquivalentTo(other.MethodSyntax)
+            && Groups.SequenceEqual(other.Groups, StringComparer.Ordinal);
 
     public override int GetHashCode()
         => HashCode.Combine(AttributeSyntax, MethodSyntax);

src/HotChocolate/Core/test/Types.Analyzers.Tests/DataLoaderTests.cs

@@ -62,6 +62,66 @@ public class Entity
             """).MatchMarkdownAsync();
     }
 
+    [Fact]
+    public async Task GenerateSource_BatchDataLoader_With_Group_Only_On_Class_MatchesSnapshot()
+    {
+        await TestHelper.GetGeneratedSourceSnapshot(
+            """
+            using System.Collections.Generic;
+            using System.Threading;
+            using System.Threading.Tasks;
+            using HotChocolate;
+            using GreenDonut;
+
+            namespace TestNamespace;
+
+            [DataLoaderGroup("Group1")]
+            internal static class TestClass
+            {
+                [DataLoader]
+                public static Task<IReadOnlyDictionary<int, Entity>> GetEntityByIdAsync(
+                    IReadOnlyList<int> entityIds,
+                    CancellationToken cancellationToken)
+                    => default!;
+            }
+
+            public class Entity
+            {
+                public int Id { get; set; }
+            }
+            """).MatchMarkdownAsync();
+    }
+
+    [Fact]
+    public async Task GenerateSource_BatchDataLoader_With_Group_Only_On_Method_MatchesSnapshot()
+    {
+        await TestHelper.GetGeneratedSourceSnapshot(
+            """
+            using System.Collections.Generic;
+            using System.Threading;
+            using System.Threading.Tasks;
+            using HotChocolate;
+            using GreenDonut;
+
+            namespace TestNamespace;
+
+            internal static class TestClass
+            {
+                [DataLoaderGroup("Group1")]
+                [DataLoader]
+                public static Task<IReadOnlyDictionary<int, Entity>> GetEntityByIdAsync(
+                    IReadOnlyList<int> entityIds,
+                    CancellationToken cancellationToken)
+                    => default!;
+            }
+
+            public class Entity
+            {
+                public int Id { get; set; }
+            }
+            """).MatchMarkdownAsync();
+    }
+
     [Fact]
     public async Task GenerateSource_GroupedDataLoader_MatchesSnapshot()
     {

src/HotChocolate/Core/test/Types.Analyzers.Tests/__snapshots__/DataLoaderTests.GenerateSource_BatchDataLoader_With_Group_MatchesSnapshot.md

@@ -69,6 +69,7 @@ namespace TestNamespace
     {
         IEntityByIdDataLoader EntityById { get; }
     }
+
     public sealed class Group1 : IGroup1
     {
         private readonly IServiceProvider _services;
@@ -96,6 +97,7 @@ namespace TestNamespace
     {
         IEntityByIdDataLoader EntityById { get; }
     }
+
     public sealed class Group2 : IGroup2
     {
         private readonly IServiceProvider _services;

src/HotChocolate/Core/test/Types.Analyzers.Tests/__snapshots__/DataLoaderTests.GenerateSource_BatchDataLoader_With_Group_Only_On_Class_MatchesSnapshot.md

@@ -0,0 +1,129 @@
+# GenerateSource_BatchDataLoader_With_Group_Only_On_Class_MatchesSnapshot
+
+## GreenDonutDataLoader.735550c.g.cs
+
+```csharp
+// <auto-generated/>
+
+#nullable enable
+#pragma warning disable
+
+using System;
+using System.Runtime.CompilerServices;
+using Microsoft.Extensions.DependencyInjection;
+using GreenDonut;
+
+namespace TestNamespace
+{
+    public interface IEntityByIdDataLoader
+        : global::GreenDonut.IDataLoader<int, global::TestNamespace.Entity>
+    {
+    }
+
+    public sealed class EntityByIdDataLoader
+        : global::GreenDonut.DataLoaderBase<int, global::TestNamespace.Entity>
+        , IEntityByIdDataLoader
+    {
+        private readonly global::System.IServiceProvider _services;
+
+        public EntityByIdDataLoader(
+            global::System.IServiceProvider services,
+            global::GreenDonut.IBatchScheduler batchScheduler,
+            global::GreenDonut.DataLoaderOptions options)
+            : base(batchScheduler, options)
+        {
+            _services = services ??
+                throw new global::System.ArgumentNullException(nameof(services));
+        }
+
+        protected override async global::System.Threading.Tasks.ValueTask FetchAsync(
+            global::System.Collections.Generic.IReadOnlyList<int> keys,
+            global::System.Memory<GreenDonut.Result<global::TestNamespace.Entity?>> results,
+            global::GreenDonut.DataLoaderFetchContext<global::TestNamespace.Entity> context,
+            global::System.Threading.CancellationToken ct)
+        {
+            var temp = await TestNamespace.TestClass.GetEntityByIdAsync(keys, ct).ConfigureAwait(false);
+            CopyResults(keys, results.Span, temp);
+        }
+
+        private void CopyResults(
+            global::System.Collections.Generic.IReadOnlyList<int> keys,
+            global::System.Span<GreenDonut.Result<global::TestNamespace.Entity?>> results,
+            global::System.Collections.Generic.IReadOnlyDictionary<int, TestNamespace.Entity> resultMap)
+        {
+            for (var i = 0; i < keys.Count; i++)
+            {
+                var key = keys[i];
+                if (resultMap.TryGetValue(key, out var value))
+                {
+                    results[i] = global::GreenDonut.Result<global::TestNamespace.Entity?>.Resolve(value);
+                }
+                else
+                {
+                    results[i] = global::GreenDonut.Result<global::TestNamespace.Entity?>.Resolve(default(global::TestNamespace.Entity));
+                }
+            }
+        }
+    }
+    public interface IGroup1
+    {
+        IEntityByIdDataLoader EntityById { get; }
+    }
+
+    public sealed class Group1 : IGroup1
+    {
+        private readonly IServiceProvider _services;
+        private IEntityByIdDataLoader? _entityById;
+
+        public Group1(IServiceProvider services)
+        {
+            _services = services
+                ?? throw new ArgumentNullException(nameof(services));
+        }
+        public IEntityByIdDataLoader EntityById
+        {
+            get
+            {
+                if (_entityById is null)
+                {
+                    _entityById = _services.GetRequiredService<IEntityByIdDataLoader>();
+                }
+
+                return _entityById!;
+            }
+        }
+    }
+}
+
+
+```
+
+## HotChocolateTypeModule.735550c.g.cs
+
+```csharp
+// <auto-generated/>
+
+#nullable enable
+#pragma warning disable
+
+using System;
+using System.Runtime.CompilerServices;
+using HotChocolate;
+using HotChocolate.Types;
+using HotChocolate.Execution.Configuration;
+
+namespace Microsoft.Extensions.DependencyInjection
+{
+    public static partial class TestsTypesRequestExecutorBuilderExtensions
+    {
+        public static IRequestExecutorBuilder AddTestsTypes(this IRequestExecutorBuilder builder)
+        {
+            builder.AddDataLoader<global::TestNamespace.IEntityByIdDataLoader, global::TestNamespace.EntityByIdDataLoader>();
+            builder.Services.AddScoped<global::TestNamespace.IGroup1, global::TestNamespace.Group1>();
+            return builder;
+        }
+    }
+}
+
+```
+

src/HotChocolate/Core/test/Types.Analyzers.Tests/__snapshots__/DataLoaderTests.GenerateSource_BatchDataLoader_With_Group_Only_On_Method_MatchesSnapshot.md

@@ -0,0 +1,129 @@
+# GenerateSource_BatchDataLoader_With_Group_Only_On_Method_MatchesSnapshot
+
+## GreenDonutDataLoader.735550c.g.cs
+
+```csharp
+// <auto-generated/>
+
+#nullable enable
+#pragma warning disable
+
+using System;
+using System.Runtime.CompilerServices;
+using Microsoft.Extensions.DependencyInjection;
+using GreenDonut;
+
+namespace TestNamespace
+{
+    public interface IEntityByIdDataLoader
+        : global::GreenDonut.IDataLoader<int, global::TestNamespace.Entity>
+    {
+    }
+
+    public sealed class EntityByIdDataLoader
+        : global::GreenDonut.DataLoaderBase<int, global::TestNamespace.Entity>
+        , IEntityByIdDataLoader
+    {
+        private readonly global::System.IServiceProvider _services;
+
+        public EntityByIdDataLoader(
+            global::System.IServiceProvider services,
+            global::GreenDonut.IBatchScheduler batchScheduler,
+            global::GreenDonut.DataLoaderOptions options)
+            : base(batchScheduler, options)
+        {
+            _services = services ??
+                throw new global::System.ArgumentNullException(nameof(services));
+        }
+
+        protected override async global::System.Threading.Tasks.ValueTask FetchAsync(
+            global::System.Collections.Generic.IReadOnlyList<int> keys,
+            global::System.Memory<GreenDonut.Result<global::TestNamespace.Entity?>> results,
+            global::GreenDonut.DataLoaderFetchContext<global::TestNamespace.Entity> context,
+            global::System.Threading.CancellationToken ct)
+        {
+            var temp = await TestNamespace.TestClass.GetEntityByIdAsync(keys, ct).ConfigureAwait(false);
+            CopyResults(keys, results.Span, temp);
+        }
+
+        private void CopyResults(
+            global::System.Collections.Generic.IReadOnlyList<int> keys,
+            global::System.Span<GreenDonut.Result<global::TestNamespace.Entity?>> results,
+            global::System.Collections.Generic.IReadOnlyDictionary<int, TestNamespace.Entity> resultMap)
+        {
+            for (var i = 0; i < keys.Count; i++)
+            {
+                var key = keys[i];
+                if (resultMap.TryGetValue(key, out var value))
+                {
+                    results[i] = global::GreenDonut.Result<global::TestNamespace.Entity?>.Resolve(value);
+                }
+                else
+                {
+                    results[i] = global::GreenDonut.Result<global::TestNamespace.Entity?>.Resolve(default(global::TestNamespace.Entity));
+                }
+            }
+        }
+    }
+    public interface IGroup1
+    {
+        IEntityByIdDataLoader EntityById { get; }
+    }
+
+    public sealed class Group1 : IGroup1
+    {
+        private readonly IServiceProvider _services;
+        private IEntityByIdDataLoader? _entityById;
+
+        public Group1(IServiceProvider services)
+        {
+            _services = services
+                ?? throw new ArgumentNullException(nameof(services));
+        }
+        public IEntityByIdDataLoader EntityById
+        {
+            get
+            {
+                if (_entityById is null)
+                {
+                    _entityById = _services.GetRequiredService<IEntityByIdDataLoader>();
+                }
+
+                return _entityById!;
+            }
+        }
+    }
+}
+
+
+```
+
+## HotChocolateTypeModule.735550c.g.cs
+
+```csharp
+// <auto-generated/>
+
+#nullable enable
+#pragma warning disable
+
+using System;
+using System.Runtime.CompilerServices;
+using HotChocolate;
+using HotChocolate.Types;
+using HotChocolate.Execution.Configuration;
+
+namespace Microsoft.Extensions.DependencyInjection
+{
+    public static partial class TestsTypesRequestExecutorBuilderExtensions
+    {
+        public static IRequestExecutorBuilder AddTestsTypes(this IRequestExecutorBuilder builder)
+        {
+            builder.AddDataLoader<global::TestNamespace.IEntityByIdDataLoader, global::TestNamespace.EntityByIdDataLoader>();
+            builder.Services.AddScoped<global::TestNamespace.IGroup1, global::TestNamespace.Group1>();
+            return builder;
+        }
+    }
+}
+
+```
+