Feature: Add snapshot tests and fix empty line generation

.gitignore

@@ -55,4 +55,10 @@ coverage/
 # NUnit
 *.VisualState.xml
 TestResult.xml
-nunit-*.xml
+nunit-*.xml
+
+# Verify snapshots (received files)
+*.received.*
+
+# User-specific files
+*.user

src/Directory.Packages.props

@@ -4,6 +4,7 @@
   </PropertyGroup>
   <ItemGroup>
     <!-- Analyzers -->
+    <PackageVersion Include="Endpointer" Version="0.1.0" />
     <PackageVersion Include="Meziantou.Analyzer" Version="2.0.285" />
     <PackageVersion Include="SonarAnalyzer.CSharp" Version="10.18.0.131500" />
     <PackageVersion Include="Roslynator.Analyzers" Version="4.15.0" />
@@ -19,5 +20,8 @@
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp.Workspaces" Version="5.0.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.2" />
     <PackageVersion Include="Microsoft.Extensions.TimeProvider.Testing" Version="10.2.0" />
+    <PackageVersion Include="Basic.Reference.Assemblies.Net80" Version="1.8.4" />
+    <PackageVersion Include="Verify.SourceGenerators" Version="2.5.0" />
+    <PackageVersion Include="Verify.TUnit" Version="31.4.3" />
   </ItemGroup>
 </Project>

src/Endpointer.Generator.Tests/Endpointer.Generator.Tests.csproj

@@ -9,6 +9,9 @@
     <PackageReference Include="TUnit" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Analyzer.Testing" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Workspaces" />
+    <PackageReference Include="Basic.Reference.Assemblies.Net80" />
+    <PackageReference Include="Verify.SourceGenerators" />
+    <PackageReference Include="Verify.TUnit" />
   </ItemGroup>
 
   <ItemGroup>

src/Endpointer.Generator.Tests/EndpointerGeneratorSnapshotTests.EndpointerRegistration_WithMultipleEndpoints_MatchesSnapshot.verified.txt

@@ -0,0 +1,36 @@
+[  
+// <auto-generated/>
+#nullable enable
+
+using Microsoft.AspNetCore.Routing;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Endpointer;
+
+public static class EndpointerExtensions
+{
+    public static IServiceCollection AddEndpointer(this IServiceCollection services)
+    {
+        services.AddScoped<App.Users.GetUserEndpoint>();
+        services.AddScoped<App.Users.CreateUserEndpoint>();
+        services.AddScoped<App.Orders.GetOrderEndpoint>();
+
+        return services;
+    }
+
+    public static IEndpointRouteBuilder MapEndpointer(this IEndpointRouteBuilder endpoints)
+    {
+        // App.Users.GetUserEndpoint
+        new App.Users.GetUserEndpoint.Endpoint().MapEndpoint(endpoints);
+
+        // App.Users.CreateUserEndpoint
+        new App.Users.CreateUserEndpoint.Endpoint().MapEndpoint(endpoints);
+
+        // App.Orders.GetOrderEndpoint
+        new App.Orders.GetOrderEndpoint.Endpoint().MapEndpoint(endpoints);
+
+        return endpoints;
+    }
+}
+
+]

src/Endpointer.Generator.Tests/EndpointerGeneratorSnapshotTests.EndpointerRegistration_WithNoEndpoints_MatchesSnapshot.verified.txt

@@ -0,0 +1,23 @@
+[  
+// <auto-generated/>
+#nullable enable
+
+using Microsoft.AspNetCore.Routing;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Endpointer;
+
+public static class EndpointerExtensions
+{
+    public static IServiceCollection AddEndpointer(this IServiceCollection services)
+    {
+        return services;
+    }
+
+    public static IEndpointRouteBuilder MapEndpointer(this IEndpointRouteBuilder endpoints)
+    {
+        return endpoints;
+    }
+}
+
+]

src/Endpointer.Generator.Tests/EndpointerGeneratorSnapshotTests.EndpointerRegistration_WithSingleEndpoint_MatchesSnapshot.verified.txt

@@ -0,0 +1,28 @@
+[  
+// <auto-generated/>
+#nullable enable
+
+using Microsoft.AspNetCore.Routing;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Endpointer;
+
+public static class EndpointerExtensions
+{
+    public static IServiceCollection AddEndpointer(this IServiceCollection services)
+    {
+        services.AddScoped<TestApp.GetTimeEndpoint>();
+
+        return services;
+    }
+
+    public static IEndpointRouteBuilder MapEndpointer(this IEndpointRouteBuilder endpoints)
+    {
+        // TestApp.GetTimeEndpoint
+        new TestApp.GetTimeEndpoint.Endpoint().MapEndpoint(endpoints);
+
+        return endpoints;
+    }
+}
+
+]

src/Endpointer.Generator.Tests/EndpointerGeneratorSnapshotTests.IEndpointInterface_MatchesSnapshot.verified.txt

@@ -0,0 +1,16 @@
+[  
+// <auto-generated/>
+#nullable enable
+
+using Microsoft.AspNetCore.Routing;
+
+namespace Endpointer;
+
+/// <summary>
+/// Marker interface for endpoint classes to be discovered by the source generator.
+/// </summary>
+public interface IEndpoint
+{
+    void MapEndpoint(IEndpointRouteBuilder endpoints);
+}
+]

src/Endpointer.Generator.Tests/EndpointerGeneratorSnapshotTests.cs

@@ -0,0 +1,149 @@
+using Basic.Reference.Assemblies;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+
+namespace Endpointer.Generator.Tests;
+
+public class EndpointerGeneratorSnapshotTests
+{
+    // Stub for ASP.NET Core types needed in test compilation
+    private const string AspNetCoreStubs = """
+        namespace Microsoft.AspNetCore.Routing
+        {
+            public interface IEndpointRouteBuilder { }
+        }
+        namespace Microsoft.Extensions.DependencyInjection
+        {
+            public interface IServiceCollection { }
+
+            public static class ServiceCollectionExtensions
+            {
+                public static IServiceCollection AddScoped<T>(this IServiceCollection services) => services;
+            }
+        }
+        """;
+
+    [Test]
+    public Task IEndpointInterface_MatchesSnapshot()
+    {
+        var (result, _) = RunGenerator("");
+
+        var generatedSources = result.Results[0].GeneratedSources
+            .Where(s => string.Equals(s.HintName, "IEndpoint.g.cs", StringComparison.Ordinal))
+            .Select(s => s.SourceText.ToString());
+
+        return Verify(generatedSources);
+    }
+
+    [Test]
+    public Task EndpointerRegistration_WithNoEndpoints_MatchesSnapshot()
+    {
+        var (result, _) = RunGenerator("");
+
+        var generatedSources = result.Results[0].GeneratedSources
+            .Where(s => string.Equals(s.HintName, "EndpointerRegistration.g.cs", StringComparison.Ordinal))
+            .Select(s => s.SourceText.ToString());
+
+        return Verify(generatedSources);
+    }
+
+    [Test]
+    public Task EndpointerRegistration_WithSingleEndpoint_MatchesSnapshot()
+    {
+        const string source = """
+            using Endpointer;
+            using Microsoft.AspNetCore.Routing;
+
+            namespace TestApp;
+
+            public class GetTimeEndpoint
+            {
+                public class Endpoint : IEndpoint
+                {
+                    public void MapEndpoint(IEndpointRouteBuilder endpoints) { }
+                }
+            }
+            """;
+
+        var (result, _) = RunGenerator(source);
+
+        var generatedSources = result.Results[0].GeneratedSources
+            .Where(s => string.Equals(s.HintName, "EndpointerRegistration.g.cs", StringComparison.Ordinal))
+            .Select(s => s.SourceText.ToString());
+
+        return Verify(generatedSources);
+    }
+
+    [Test]
+    public Task EndpointerRegistration_WithMultipleEndpoints_MatchesSnapshot()
+    {
+        const string source = """
+            using Endpointer;
+            using Microsoft.AspNetCore.Routing;
+
+            namespace App.Users
+            {
+                public class GetUserEndpoint
+                {
+                    public class Endpoint : IEndpoint
+                    {
+                        public void MapEndpoint(IEndpointRouteBuilder endpoints) { }
+                    }
+                }
+
+                public class CreateUserEndpoint
+                {
+                    public class Endpoint : IEndpoint
+                    {
+                        public void MapEndpoint(IEndpointRouteBuilder endpoints) { }
+                    }
+                }
+            }
+
+            namespace App.Orders
+            {
+                public class GetOrderEndpoint
+                {
+                    public class Endpoint : IEndpoint
+                    {
+                        public void MapEndpoint(IEndpointRouteBuilder endpoints) { }
+                    }
+                }
+            }
+            """;
+
+        var (result, _) = RunGenerator(source);
+
+        var generatedSources = result.Results[0].GeneratedSources
+            .Where(s => string.Equals(s.HintName, "EndpointerRegistration.g.cs", StringComparison.Ordinal))
+            .Select(s => s.SourceText.ToString());
+
+        return Verify(generatedSources);
+    }
+
+    private static (GeneratorDriverRunResult Result, Compilation OutputCompilation) RunGenerator(string source)
+    {
+        var syntaxTrees = new List<SyntaxTree>
+        {
+            CSharpSyntaxTree.ParseText(AspNetCoreStubs),
+        };
+
+        if (!string.IsNullOrEmpty(source))
+        {
+            syntaxTrees.Add(CSharpSyntaxTree.ParseText(source));
+        }
+
+        var compilation = CSharpCompilation.Create(
+            assemblyName: "TestAssembly",
+            syntaxTrees: syntaxTrees,
+            references: Net80.References.All,
+            options: new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary));
+
+        var generator = new EndpointerGenerator();
+
+        GeneratorDriver driver = CSharpGeneratorDriver.Create(generator);
+        driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var outputCompilation, out _);
+
+        return (driver.GetRunResult(), outputCompilation);
+    }
+}