[Draft] Add generated C# full-generation benchmarks

.chronus/changes/mtg-hybrid-reference-map-2026-06-19-08-41-23.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/http-client-csharp"
+---
+
+Improve C# generator post-processing reference-map parity and performance.

.chronus/changes/mtg-manual-name-reduction-experiment-2026-06-23-07-14-07.md

@@ -0,0 +1,7 @@
+---
+changeKind: internal
+packages:
+  - "@typespec/http-client-csharp"
+---
+
+Tune hybrid provider reference-map benchmark parity and performance.

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/ClientProvider.cs

@@ -424,6 +424,73 @@ private IReadOnlyList<ParameterProvider> GetClientParameters()
 
         protected override string BuildName() => _inputClient.IsExactName ? _inputClient.Name : _inputClient.Name.ToIdentifierName();
 
+        protected override IReadOnlyList<string> BuildHelperDependencyNames()
+        {
+            foreach (var method in Methods.OfType<ScmMethodProvider>())
+            {
+                if (method.BodyStatements != null)
+                {
+                    return ["CancellationTokenExtensions", "ClientPipelineExtensions"];
+                }
+            }
+
+            return [];
+        }
+
+        protected override IReadOnlyList<CSharpType> BuildBodyDependencyTypes()
+        {
+            var dependencies = new List<CSharpType>();
+            foreach (var method in Methods.OfType<ScmMethodProvider>())
+            {
+                if (method.BodyStatements == null)
+                {
+                    continue;
+                }
+
+                if (method.CollectionDefinition != null)
+                {
+                    dependencies.Add(method.CollectionDefinition.Type);
+                }
+
+                if (method.ServiceMethod == null)
+                {
+                    continue;
+                }
+
+                AddInputTypeDependency(dependencies, method.ServiceMethod.Response.Type);
+                AddInputTypeDependency(dependencies, method.ServiceMethod.Exception?.Type);
+                foreach (var parameter in method.ServiceMethod.Parameters)
+                {
+                    AddInputTypeDependency(dependencies, parameter.Type);
+                }
+
+                foreach (var parameter in method.ServiceMethod.Operation.Parameters)
+                {
+                    AddInputTypeDependency(dependencies, parameter.Type);
+                }
+
+                foreach (var response in method.ServiceMethod.Operation.Responses)
+                {
+                    AddInputTypeDependency(dependencies, response.BodyType);
+                    foreach (var header in response.Headers)
+                    {
+                        AddInputTypeDependency(dependencies, header.Type);
+                    }
+                }
+            }
+
+            return dependencies;
+        }
+
+        private static void AddInputTypeDependency(List<CSharpType> dependencies, InputType? inputType)
+        {
+            var type = inputType == null ? null : ScmCodeModelGenerator.Instance.TypeFactory.CreateCSharpType(inputType);
+            if (type != null)
+            {
+                dependencies.Add(type);
+            }
+        }
+
         protected override FieldProvider[] BuildFields()
         {
             List<FieldProvider> fields = [EndpointField];

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/CollectionResultDefinition.cs

@@ -217,6 +217,22 @@ private bool HasPagingOperationNameCollision(string operationName)
         protected override TypeSignatureModifiers BuildDeclarationModifiers()
             => TypeSignatureModifiers.Internal | TypeSignatureModifiers.Partial | TypeSignatureModifiers.Class;
 
+        protected override IReadOnlyList<CSharpType> BuildBodyDependencyTypes()
+        {
+            var dependencies = new List<CSharpType> { Client.Type, ResponseModelType, NextPagePropertyType };
+            if (ItemModelType != null)
+            {
+                dependencies.Add(ItemModelType);
+            }
+
+            foreach (var field in RequestFields)
+            {
+                dependencies.Add(field.Type);
+            }
+
+            return dependencies;
+        }
+
         protected override FieldProvider[] BuildFields() => [ClientField, .. RequestFields];
 
         protected override CSharpType[] BuildImplements() =>

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/MrwSerializationTypeDefinition.cs

@@ -117,6 +117,10 @@ public MrwSerializationTypeDefinition(InputModelType inputModel, ModelProvider m
 
         protected override CSharpType? BuildBaseType() => _model.BaseType;
 
+        protected override IReadOnlyList<string> BuildHelperDependencyNames() => _rawDataField != null || _additionalProperties.Value.Length > 0
+            ? ["ChangeTrackingDictionary"]
+            : [];
+
         protected override SuppressionStatement[] BuildDisabledFileWarnings()
         {
             if (_model.CanonicalView.Properties.Any(p => ScmModelProvider.IsFileBinaryContentType(p.Type)))

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/MultipartFormDataSerializationDefinition.cs

@@ -51,6 +51,12 @@ protected override string BuildRelativeFilePath()
             return Path.Combine("src", "Generated", "Models", $"{Name}.Serialization.Multipart.cs");
         }
 
+        protected override IReadOnlyList<string> BuildHelperDependencyNames() => _model.Properties.Any(
+            prop => prop.WireInfo != null && !prop.WireInfo.IsRequired &&
+                (prop.Type is { IsCollection: true, IsReadOnlyMemory: false } || prop.Type.IsDictionary))
+            ? ["Optional"]
+            : [];
+
         protected override SuppressionStatement[] BuildDisabledFileWarnings()
             => [new SuppressionStatement(null, Literal(ScmModelProvider.FileBinaryContentDiagnosticId), ScmModelProvider.ScmEvaluationTypeSuppressionJustification)];
 

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/RestClientProvider.cs

@@ -78,6 +78,36 @@ protected override FieldProvider[] BuildFields()
             return [.. pipelineMessage20xClassifiersFields];
         }
 
+        protected override IReadOnlyList<string> BuildHelperDependencyNames()
+        {
+            var dependencies = new HashSet<string>(StringComparer.Ordinal)
+            {
+                "ClientUriBuilder"
+            };
+            foreach (var serviceMethod in _inputClient.Methods)
+            {
+                foreach (var parameter in serviceMethod.Operation.Parameters)
+                {
+                    if (parameter is not InputHeaderParameter and not InputQueryParameter)
+                    {
+                        continue;
+                    }
+
+                    var type = ScmCodeModelGenerator.Instance.TypeFactory.CreateCSharpType(parameter.Type);
+                    if (type?.IsDictionary == true)
+                    {
+                        dependencies.Add("ChangeTrackingDictionary");
+                    }
+                    else if (type?.IsCollection == true)
+                    {
+                        dependencies.Add("ChangeTrackingList");
+                    }
+                }
+            }
+
+            return [.. dependencies];
+        }
+
         protected override ScmMethodProvider[] BuildMethods()
         {
             List<ScmMethodProvider> methods = new List<ScmMethodProvider>();