implement the feature of changing the name of a model

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/CSharpGen.cs

@@ -7,6 +7,7 @@
 using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.Generator.CSharp.Primitives;
+using Microsoft.Generator.CSharp.SourceInput;
 
 namespace Microsoft.Generator.CSharp
 {
@@ -29,6 +30,8 @@ public async Task ExecuteAsync()
             var generatedTestOutputPath = Path.Combine(outputPath, "..", "..", "tests", GeneratedFolderName);
 
             GeneratedCodeWorkspace workspace = await GeneratedCodeWorkspace.Create();
+            GeneratedCodeWorkspace existingCode = GeneratedCodeWorkspace.CreateExistingCodeProject(CodeModelPlugin.Instance.Configuration.ProjectDirectory, generatedSourceOutputPath);
+            SourceInputModel.Initialize(await existingCode.GetCompilationAsync());
 
             var output = CodeModelPlugin.Instance.OutputLibrary;
             Directory.CreateDirectory(Path.Combine(generatedSourceOutputPath, "Models"));

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/PostProcessing/GeneratedCodeWorkspace.cs

@@ -47,6 +47,14 @@ public static void Initialize()
             _cachedProject = Task.Run(CreateGeneratedCodeProject);
         }
 
+        internal async Task<CSharpCompilation> GetCompilationAsync()
+        {
+            var compilation = await _project.GetCompilationAsync() as CSharpCompilation;
+            Debug.Assert(compilation != null);
+
+            return compilation;
+        }
+
         public void AddPlainFiles(string name, string content)
         {
             PlainFiles.Add(name, content);
@@ -140,17 +148,18 @@ internal static async Task<GeneratedCodeWorkspace> Create()
             return new GeneratedCodeWorkspace(generatedCodeProject);
         }
 
-        public static GeneratedCodeWorkspace CreateExistingCodeProject(string outputDirectory)
+        internal static GeneratedCodeWorkspace CreateExistingCodeProject(string projectDirectory, string generatedDirectory)
         {
             var workspace = new AdhocWorkspace();
             var newOptionSet = workspace.Options.WithChangedOption(FormattingOptions.NewLine, LanguageNames.CSharp, _newLine);
             workspace.TryApplyChanges(workspace.CurrentSolution.WithOptions(newOptionSet));
             Project project = workspace.AddProject("ExistingCode", LanguageNames.CSharp);
 
-            if (Path.IsPathRooted(outputDirectory))
+            if (Path.IsPathRooted(projectDirectory))
             {
-                outputDirectory = Path.GetFullPath(outputDirectory);
-                project = AddDirectory(project, outputDirectory, null);
+                projectDirectory = Path.GetFullPath(projectDirectory);
+
+                project = AddDirectory(project, projectDirectory, skipPredicate: sourceFile => sourceFile.StartsWith(generatedDirectory));
             }
 
             project = project
@@ -161,7 +170,7 @@ public static GeneratedCodeWorkspace CreateExistingCodeProject(string outputDire
             return new GeneratedCodeWorkspace(project);
         }
 
-        public static async Task<Compilation?> CreatePreviousContractFromDll(string xmlDocumentationpath, string dllPath)
+        internal static async Task<Compilation?> CreatePreviousContractFromDll(string xmlDocumentationpath, string dllPath)
         {
             var workspace = new AdhocWorkspace();
             Project project = workspace.AddProject("PreviousContract", LanguageNames.CSharp);

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/NamedTypeSymbolProvider.cs

@@ -6,13 +6,12 @@
 using System.Linq;
 using System.Xml.Linq;
 using Microsoft.CodeAnalysis;
-using Microsoft.Generator.CSharp.Expressions;
 using Microsoft.Generator.CSharp.Primitives;
 using Microsoft.Generator.CSharp.Statements;
 
 namespace Microsoft.Generator.CSharp.Providers
 {
-    public class NamedTypeSymbolProvider : TypeProvider
+    public sealed class NamedTypeSymbolProvider : TypeProvider
     {
         private INamedTypeSymbol _namedTypeSymbol;
 

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/Providers/TypeProvider.cs

@@ -6,12 +6,29 @@
 using System.Linq;
 using Microsoft.Generator.CSharp.Expressions;
 using Microsoft.Generator.CSharp.Primitives;
+using Microsoft.Generator.CSharp.SourceInput;
 using Microsoft.Generator.CSharp.Statements;
 
 namespace Microsoft.Generator.CSharp.Providers
 {
     public abstract class TypeProvider
     {
+        private Lazy<NamedTypeSymbolProvider?> _customization;
+        protected TypeProvider()
+        {
+            _customization = new(GetCustomizationProvider);
+        }
+
+        private NamedTypeSymbolProvider? GetCustomizationProvider()
+        {
+            if (this is NamedTypeSymbolProvider)
+                return null;
+            var type = SourceInputModel.Instance.FindForType(GetNamespace(), BuildName());
+            return type != null ? new NamedTypeSymbolProvider(type) : null;
+        }
+
+        public NamedTypeSymbolProvider? Customization => _customization.Value;
+
         protected string? _deprecated;
 
         /// <summary>
@@ -22,10 +39,13 @@ public abstract class TypeProvider
 
         private string? _relativeFilePath;
 
-        public string Name => _name ??= BuildName();
+        public string Name => _name ??= GetName();
 
         private string? _name;
 
+        private string GetName()
+            => Customization?.Name ?? BuildName();
+
         protected virtual FormattableString Description { get; } = FormattableStringHelpers.Empty;
 
         private XmlDocProvider? _xmlDocs;
@@ -45,7 +65,7 @@ public string? Deprecated
         private CSharpType? _type;
         public CSharpType Type => _type ??= new(
             this,
-            GetNamespace(),
+            Customization?.GetNamespace() ?? GetNamespace(),
             GetTypeArguments(),
             GetBaseType());
 

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/src/SourceInput/SourceInputModel.cs

@@ -11,19 +11,28 @@
 using Microsoft.CodeAnalysis;
 using Microsoft.Generator.CSharp.Customization;
 using Microsoft.Generator.CSharp.Primitives;
-using Microsoft.Generator.CSharp.Providers;
 using NuGet.Configuration;
 
 namespace Microsoft.Generator.CSharp.SourceInput
 {
-    internal sealed class SourceInputModel
+    internal class SourceInputModel
     {
         private static SourceInputModel? _instance;
-        public static SourceInputModel Instance => _instance ?? throw new InvalidOperationException("SourceInputModel has not been initialized");
+        public static SourceInputModel Instance
+        {
+            get
+            {
+                return _instance ?? throw new InvalidOperationException("SourceInputModel has not been initialized");
+            }
+            set
+            {
+                _instance = value;
+            }
+        }
 
-        public static void Initialize(Compilation customization, CompilationCustomCode? existingCompilation = null)
+        public static void Initialize(Compilation customization, CompilationCustomCode? previousContract = null)
         {
-            _instance = new SourceInputModel(customization, existingCompilation);
+            _instance = new SourceInputModel(customization, previousContract);
         }
 
         private readonly CompilationCustomCode? _existingCompilation;
@@ -33,7 +42,7 @@ public static void Initialize(Compilation customization, CompilationCustomCode?
         public Compilation Customization { get; }
         public Compilation? PreviousContract { get; }
 
-        private SourceInputModel(Compilation customization, CompilationCustomCode? existingCompilation = null)
+        internal SourceInputModel(Compilation customization, CompilationCustomCode? existingCompilation = null)
         {
             Customization = customization;
             PreviousContract = LoadBaselineContract().GetAwaiter().GetResult();
@@ -77,9 +86,8 @@ private SourceInputModel(Compilation customization, CompilationCustomCode? exist
             return _existingCompilation?.FindMethod(namespaceName, typeName, methodName, parameters);
         }
 
-        public INamedTypeSymbol? FindForType(string name)
+        public INamedTypeSymbol? FindForType(string ns, string name)
         {
-            var ns = CodeModelPlugin.Instance.Configuration.ModelNamespace;
             var fullyQualifiedMetadataName = $"{ns}.{name}";
             if (!_nameMap.TryGetValue(name, out var type) &&
                 !_nameMap.TryGetValue(fullyQualifiedMetadataName, out type))

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/test/Providers/ModelProviders/ModelCustomizationTests.cs

@@ -0,0 +1,64 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.Generator.CSharp.Input;
+using Microsoft.Generator.CSharp.Providers;
+using Microsoft.Generator.CSharp.Tests.Common;
+using NUnit.Framework;
+
+namespace Microsoft.Generator.CSharp.Tests.Providers.ModelProviders
+{
+    public class ModelCustomizationTests
+    {
+        // Validates that the property body's setter is correctly set based on the property type
+        [TestCase]
+        public void TestCustomization_CanChangeModelName()
+        {
+            SyntaxTree syntaxTree = CSharpSyntaxTree.ParseText(_customizationCode);
+            CSharpCompilation compilation = CSharpCompilation.Create("ExistingCode")
+                .WithOptions(new CSharpCompilationOptions(OutputKind.ConsoleApplication))
+                .AddReferences(MetadataReference.CreateFromFile(typeof(object).Assembly.Location))
+                .AddSyntaxTrees(syntaxTree);
+            MockHelpers.LoadMockPlugin(customization: compilation);
+
+            var props = new[]
+            {
+                InputFactory.Property("prop1", InputFactory.Array(InputPrimitiveType.String))
+            };
+
+            var inputModel = InputFactory.Model("mockInputModel", properties: props);
+            var modelTypeProvider = new ModelProvider(inputModel);
+
+            Assert.AreEqual("CustomizedModel", modelTypeProvider.Type.Name);
+            Assert.AreEqual("NewNamespace.Models", modelTypeProvider.Type.Namespace);
+        }
+
+        private const string _customizationCode = @"#nullable disable
+
+using System;
+
+namespace NewNamespace
+{
+    [AttributeUsage(AttributeTargets.Class)]
+    internal class CodeGenTypeAttribute : Attribute
+    {
+        public string OriginalName { get; }
+
+        public CodeGenTypeAttribute(string originalName)
+        {
+            OriginalName = originalName;
+        }
+    }
+}
+namespace NewNamespace.Models
+{
+    [CodeGenType(""MockInputModel"")]
+    public partial class CustomizedModel
+    {
+    }
+}
+";
+    }
+}

packages/http-client-csharp/generator/Microsoft.Generator.CSharp/test/TestHelpers/MockHelpers.cs

@@ -1,14 +1,15 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-using System.IO;
 using System;
-using System.Collections.Generic;
+using System.IO;
+using Microsoft.CodeAnalysis;
 using Microsoft.Generator.CSharp.Input;
 using Microsoft.Generator.CSharp.Primitives;
-using Moq.Protected;
-using Moq;
+using Microsoft.Generator.CSharp.SourceInput;
 using Microsoft.Generator.CSharp.Tests.Common;
+using Moq;
+using Moq.Protected;
 
 namespace Microsoft.Generator.CSharp.Tests
 {
@@ -20,7 +21,8 @@ public static Mock<CodeModelPlugin> LoadMockPlugin(
             Func<InputType, CSharpType>? createCSharpTypeCore = null,
             Func<OutputLibrary>? createOutputLibrary = null,
             string? configuration = null,
-            InputModelType[]? inputModelTypes = null)
+            InputModelType[]? inputModelTypes = null,
+            Compilation? customization = null)
         {
             var configFilePath = Path.Combine(AppContext.BaseDirectory, TestHelpersFolder);
             // initialize the singleton instance of the plugin
@@ -48,6 +50,18 @@ public static Mock<CodeModelPlugin> LoadMockPlugin(
             mockPlugin.SetupGet(p => p.TypeFactory).Returns(mockTypeFactory.Object);
 
             CodeModelPlugin.Instance = mockPlugin.Object;
+
+            if (customization == null)
+            {
+                var workspace = new AdhocWorkspace();
+                Project project = workspace.AddProject("ExistingCode", LanguageNames.CSharp);
+                customization = project.GetCompilationAsync().GetAwaiter().GetResult()!;
+            }
+
+            var sourceInputModel = new Mock<SourceInputModel>(() => new SourceInputModel(customization, null)) { CallBase = true };
+
+            SourceInputModel.Instance = sourceInputModel.Object;
+
             return mockPlugin;
         }
     }