fix: formatting of nested types within generic types

Source/aweXpect.Core/Formatting/ValueFormatters.Type.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
-using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
+using System.Linq;
 using System.Text;
 using aweXpect.Core.Helpers;
 
@@ -103,10 +104,16 @@ public static void Format(
 		FormatType(value, stringBuilder);
 	}
 
-#pragma warning disable S3776 // https://rules.sonarsource.com/csharp/RSPEC-3776
 	private static void FormatType(
 		Type value,
 		StringBuilder stringBuilder)
+		=> FormatType(value, stringBuilder, null);
+
+#pragma warning disable S3776 // https://rules.sonarsource.com/csharp/RSPEC-3776
+	private static void FormatType(
+		Type value,
+		StringBuilder stringBuilder,
+		Type[]? genericArguments)
 	{
 		if (value == typeof(void))
 		{
@@ -125,17 +132,31 @@ private static void FormatType(
 		{
 			if (value.IsNested && value.DeclaringType is not null)
 			{
-				FormatType(value.DeclaringType, stringBuilder);
+				Type[]? declaringTypeGenericArguments = null;
+				if (value.IsGenericType)
+				{
+					int arity = GetArityOfGenericParameters(value.DeclaringType);
+					declaringTypeGenericArguments = [..value.GenericTypeArguments.Take(arity)];
+					genericArguments = [..(genericArguments ?? value.GenericTypeArguments).Skip(arity)];
+				}
+
+				FormatType(value.DeclaringType, stringBuilder, declaringTypeGenericArguments);
 				stringBuilder.Append('.');
 			}
 
 			if (value.IsGenericType)
 			{
 				Type genericTypeDefinition = value.GetGenericTypeDefinition();
 				stringBuilder.Append(genericTypeDefinition.Name.SubstringUntilFirst('`'));
+				if (genericArguments?.Length == 0)
+				{
+					return;
+				}
+
 				stringBuilder.Append('<');
 				bool isFirstArgument = true;
-				foreach (Type argument in value.GetGenericArguments())
+				genericArguments ??= value.GetGenericArguments();
+				foreach (var argument in genericArguments)
 				{
 					if (!isFirstArgument)
 					{
@@ -158,6 +179,20 @@ private static void FormatType(
 		}
 	}
 #pragma warning restore S3776
+
+	private static int GetArityOfGenericParameters(Type type)
+	{
+		int tickIndex = type.Name.LastIndexOf('`');
+		if (tickIndex != -1)
+		{
+			var arityStr = type.Name[(tickIndex + 1)..];
+			if (int.TryParse(arityStr, NumberStyles.None, CultureInfo.InvariantCulture, out int arity))
+			{
+				return arity;
+			}
+		}
+		return 0;
+	}
 
 	private static bool AppendedPrimitiveAlias(Type value, StringBuilder stringBuilder)
 	{

Tests/aweXpect.Core.Tests/Formatting/ValueFormatters.TypeTests.cs

@@ -26,6 +26,38 @@ public async Task NestedGenericTypes_ShouldIncludeTheDeclaringTypeAndName()
 			await That(sb.ToString()).IsEqualTo(expectedResult);
 		}
 
+		[Fact]
+		public async Task NestedGenericTypeInGenericTypes_ShouldIncludeTheDeclaringTypeAndName()
+		{
+			Type value = typeof(NestedGenericType<TypeTests>.InnerClass<int, string>);
+			string expectedResult = "ValueFormatters.TypeTests.NestedGenericType<ValueFormatters.TypeTests>.InnerClass<int, string>";
+			StringBuilder sb = new();
+
+			string result = Formatter.Format(value);
+			string objectResult = Formatter.Format((object?)value);
+			Formatter.Format(sb, value);
+
+			await That(result).IsEqualTo(expectedResult);
+			await That(objectResult).IsEqualTo(expectedResult);
+			await That(sb.ToString()).IsEqualTo(expectedResult);
+		}
+
+		[Fact]
+		public async Task NestedTypeInGenericTypes_ShouldIncludeTheDeclaringTypeAndName()
+		{
+			Type value = typeof(NestedGenericType<TypeTests>.InnerRegularClass);
+			string expectedResult = "ValueFormatters.TypeTests.NestedGenericType<ValueFormatters.TypeTests>.InnerRegularClass";
+			StringBuilder sb = new();
+
+			string result = Formatter.Format(value);
+			string objectResult = Formatter.Format((object?)value);
+			Formatter.Format(sb, value);
+
+			await That(result).IsEqualTo(expectedResult);
+			await That(objectResult).IsEqualTo(expectedResult);
+			await That(sb.ToString()).IsEqualTo(expectedResult);
+		}
+
 		[Fact]
 		public async Task NestedTypes_ShouldIncludeTheDeclaringTypeAndName()
 		{
@@ -259,7 +291,12 @@ public async Task WhenVoid_ShouldUseSimpleName()
 		}
 
 		// ReSharper disable once UnusedTypeParameter
-		private class NestedGenericType<T>;
+		private class NestedGenericType<T>
+		{
+			public sealed class InnerClass<T1, T2>;
+
+			public sealed class InnerRegularClass;
+		}
 
 		// ReSharper disable once UnusedParameter.Local
 		private static void DummyMethodToGetSpecialTypes<TParameter>(TParameter value)