Fix dotnet format and coverage issues

- Add UTF-8 BOM to files missing it (CHARSET format errors)
- Rename ModelBuilder static fields to _camelCase (IDE1006)
- Add InternalsVisibleTo so the generator test project can reach
  the internal model types
- Add ModelEqualityTests + EmitterTests and extra generator behavior
  tests, raising generator coverage from ~81% to ~98%

Author: tillig

bench/Autofac.Extras.AggregateService.Bench/Program.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 using BenchmarkDotNet.Jobs;

src/Autofac.Extras.AggregateService.SourceGenerator/AggregateServiceModel.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 namespace Autofac.Extras.AggregateService.SourceGenerator;

src/Autofac.Extras.AggregateService.SourceGenerator/MemberKind.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 namespace Autofac.Extras.AggregateService.SourceGenerator;

src/Autofac.Extras.AggregateService.SourceGenerator/MemberModel.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 namespace Autofac.Extras.AggregateService.SourceGenerator;

src/Autofac.Extras.AggregateService.SourceGenerator/ModelBuilder.cs

@@ -12,11 +12,11 @@ namespace Autofac.Extras.AggregateService.SourceGenerator;
 /// </summary>
 internal static class ModelBuilder
 {
-    private static readonly SymbolDisplayFormat FullyQualifiedFormat = SymbolDisplayFormat.FullyQualifiedFormat;
+    private static readonly SymbolDisplayFormat _fullyQualifiedFormat = SymbolDisplayFormat.FullyQualifiedFormat;
 
     // Fully-qualified name without any type parameter/argument list, so the emitter can build
     // the open (IFoo<,>) and closed (IFoo<T>) forms itself without double-appending.
-    private static readonly SymbolDisplayFormat FullyQualifiedNoTypeParametersFormat =
+    private static readonly SymbolDisplayFormat _fullyQualifiedNoTypeParametersFormat =
         SymbolDisplayFormat.FullyQualifiedFormat.WithGenericsOptions(SymbolDisplayGenericsOptions.None);
 
     /// <summary>
@@ -60,7 +60,7 @@ internal static class ModelBuilder
             return null;
         }
 
-        var fullyQualified = definition.ToDisplayString(FullyQualifiedNoTypeParametersFormat);
+        var fullyQualified = definition.ToDisplayString(_fullyQualifiedNoTypeParametersFormat);
         var ns = definition.ContainingNamespace.IsGlobalNamespace
             ? string.Empty
             : definition.ContainingNamespace.ToDisplayString();
@@ -174,7 +174,7 @@ private static bool IsAccessor(IMethodSymbol method)
             return null;
         }
 
-        var propertyType = property.Type.ToDisplayString(FullyQualifiedFormat);
+        var propertyType = property.Type.ToDisplayString(_fullyQualifiedFormat);
         return new MemberModel(
             MemberKind.Property,
             property.Name,
@@ -204,7 +204,7 @@ private static bool IsAccessor(IMethodSymbol method)
             }
         }
 
-        var returnType = method.ReturnType.ToDisplayString(FullyQualifiedFormat);
+        var returnType = method.ReturnType.ToDisplayString(_fullyQualifiedFormat);
         var typeParameters = method.TypeParameters.Select(BuildTypeParameter).ToArray();
 
         // Void methods have no return type to resolve; the runtime throws when they are invoked,
@@ -245,7 +245,7 @@ private static ParameterModel[] BuildParameters(IMethodSymbol method)
             .OrderBy(p => p.Ordinal)
             .Select(p => new ParameterModel(
                 p.Name,
-                p.Type.ToDisplayString(FullyQualifiedFormat),
+                p.Type.ToDisplayString(_fullyQualifiedFormat),
                 BuildParameterModifier(p)))
             .ToArray();
 
@@ -290,7 +290,7 @@ private static string BuildConstraintClause(ITypeParameterSymbol typeParameter)
 
         foreach (var constraintType in typeParameter.ConstraintTypes)
         {
-            constraints.Add(constraintType.ToDisplayString(FullyQualifiedFormat));
+            constraints.Add(constraintType.ToDisplayString(_fullyQualifiedFormat));
         }
 
         // The parameterless-constructor constraint must come last and is not combinable with the

src/Autofac.Extras.AggregateService.SourceGenerator/ParameterModel.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 namespace Autofac.Extras.AggregateService.SourceGenerator;

src/Autofac.Extras.AggregateService.SourceGenerator/Properties/AssemblyInfo.cs

@@ -0,0 +1,6 @@
+// Copyright (c) Autofac Project. All rights reserved.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("Autofac.Extras.AggregateService.SourceGenerator.Test, PublicKey=00240000048000009400000006020000002400005253413100040000010001008728425885ef385e049261b18878327dfaaf0d666dea3bd2b0e4f18b33929ad4e5fbc9087e7eda3c1291d2de579206d9b4292456abffbe8be6c7060b36da0c33b883e3878eaf7c89fddf29e6e27d24588e81e86f3a22dd7b1a296b5f06fbfb500bbd7410faa7213ef4e2ce7622aefc03169b0324bcd30ccfe9ac8204e4960be6")]

test/Autofac.Extras.AggregateService.AotSmokeTest/Program.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Autofac Project. All rights reserved.
+// Copyright (c) Autofac Project. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
 using Autofac;

test/Autofac.Extras.AggregateService.SourceGenerator.Test/EmitterTests.cs

@@ -0,0 +1,46 @@
+// Copyright (c) Autofac Project. All rights reserved.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+
+namespace Autofac.Extras.AggregateService.SourceGenerator.Test;
+
+/// <summary>
+/// Direct unit tests for <see cref="Emitter"/> branches that the full-compilation
+/// harness cannot reach - notably the <c>ModuleInitializerAttribute</c> polyfill,
+/// which is only emitted when the consuming compilation lacks the attribute (a
+/// netstandard2.0 / net472 target), whereas the test host always has it.
+/// </summary>
+public class EmitterTests
+{
+    [Fact]
+    public void EmitRegistrations_EmitsModuleInitializerPolyfillWhenRequested()
+    {
+        var model = CreateClosedModel();
+
+        var source = Emitter.EmitRegistrations(new[] { model }, needsModuleInitializerPolyfill: true);
+
+        Assert.Contains("namespace System.Runtime.CompilerServices", source, StringComparison.Ordinal);
+        Assert.Contains("class ModuleInitializerAttribute", source, StringComparison.Ordinal);
+        Assert.Contains("GeneratedAggregateServiceModuleInitializer", source, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void EmitRegistrations_OmitsModuleInitializerPolyfillWhenNotRequested()
+    {
+        var model = CreateClosedModel();
+
+        var source = Emitter.EmitRegistrations(new[] { model }, needsModuleInitializerPolyfill: false);
+
+        Assert.DoesNotContain("class ModuleInitializerAttribute", source, StringComparison.Ordinal);
+        Assert.Contains("GeneratedAggregateServiceModuleInitializer", source, StringComparison.Ordinal);
+    }
+
+    private static AggregateServiceModel CreateClosedModel()
+        => new AggregateServiceModel(
+            interfaceFullyQualifiedName: "global::TestConsumer.IMyAggregate",
+            interfaceNamespace: "TestConsumer",
+            interfaceMinimalName: "TestConsumer_IMyAggregate",
+            backingClassName: "__TestConsumer_IMyAggregate_Aggregate",
+            isOpenGeneric: false,
+            typeParameters: new EquatableArray<TypeParameterModel>(System.Array.Empty<TypeParameterModel>()),
+            members: new EquatableArray<MemberModel>(System.Array.Empty<MemberModel>()));
+}

test/Autofac.Extras.AggregateService.SourceGenerator.Test/GeneratorBehaviorTests.cs

@@ -180,4 +180,133 @@ public static void Configure(ContainerBuilder builder)
 
         Assert.Single(result.Diagnostics, d => d.Id == "AGSVC001");
     }
+
+    [Fact]
+    public void NonInterfaceTypeArgumentIsNotGenerated()
+    {
+        // CreateInstance<T> where T is not an interface cannot be an aggregate service; the
+        // generator must skip it (the runtime throws ArgumentException instead).
+        var source = @"using Autofac;
+using Autofac.Extras.AggregateService;
+
+namespace TestConsumer
+{
+    public static class Registration
+    {
+        public static object Configure(IComponentContext context)
+        {
+            return AggregateServiceGenerator.CreateInstance<string>(context);
+        }
+    }
+}";
+
+        var driver = GeneratorTestHarness.Run(source);
+        var result = driver.GetRunResult();
+
+        Assert.Empty(result.GeneratedTrees);
+    }
+
+    [Fact]
+    public void NestedInterfaceIsNotGenerated()
+    {
+        // An aggregate interface nested inside another type is not supported; the generator skips
+        // it and the runtime falls back to the dynamic proxy.
+        var source = @"using Autofac;
+using Autofac.Extras.AggregateService;
+
+namespace TestConsumer
+{
+    public interface IDep { }
+
+    public class Outer
+    {
+        public interface INested
+        {
+            IDep Dep { get; }
+        }
+    }
+
+    public static class Registration
+    {
+        public static void Configure(ContainerBuilder builder)
+        {
+            builder.RegisterAggregateService<Outer.INested>();
+        }
+    }
+}";
+
+        var driver = GeneratorTestHarness.Run(source);
+        var result = driver.GetRunResult();
+
+        Assert.Empty(result.GeneratedTrees);
+        Assert.Single(result.Diagnostics, d => d.Id == "AGSVC001");
+    }
+
+    [Fact]
+    public void InterfaceWithEventIsNotGenerated()
+    {
+        // Events are an unsupported member shape; the generator skips the interface and reports
+        // AGSVC001 so the dynamic-proxy fallback is visible.
+        var source = @"using System;
+using Autofac;
+using Autofac.Extras.AggregateService;
+
+namespace TestConsumer
+{
+    public interface IDep { }
+
+    public interface IMyAggregate
+    {
+        IDep Dep { get; }
+
+        event EventHandler Something;
+    }
+
+    public static class Registration
+    {
+        public static void Configure(ContainerBuilder builder)
+        {
+            builder.RegisterAggregateService<IMyAggregate>();
+        }
+    }
+}";
+
+        var driver = GeneratorTestHarness.Run(source);
+        var result = driver.GetRunResult();
+
+        Assert.Empty(result.GeneratedTrees);
+        Assert.Single(result.Diagnostics, d => d.Id == "AGSVC001");
+    }
+
+    [Fact]
+    public void NullConditionalInvocationIsDiscovered()
+    {
+        // A null-conditional registration call (builder?.RegisterAggregateService<T>()) uses a
+        // MemberBindingExpressionSyntax; the generator must still discover it.
+        var source = @"using Autofac;
+using Autofac.Extras.AggregateService;
+
+namespace TestConsumer
+{
+    public interface IDep { }
+
+    public interface IMyAggregate
+    {
+        IDep Dep { get; }
+    }
+
+    public static class Registration
+    {
+        public static void Configure(ContainerBuilder builder)
+        {
+            builder?.RegisterAggregateService<IMyAggregate>();
+        }
+    }
+}";
+
+        var driver = GeneratorTestHarness.Run(source);
+        var result = driver.GetRunResult();
+
+        Assert.Contains(result.GeneratedTrees, t => t.FilePath.Contains("IMyAggregate", StringComparison.Ordinal));
+    }
 }