perf: switch typeSb to use ValueStringBuilder

Author: TimothyMakkison

TUnit.Engine/Services/TestIdentifierService.cs

@@ -89,44 +89,41 @@ private static void WriteTypeNameWithGenerics(ref ValueStringBuilder vsb, Type t
     {
         // Build the full type hierarchy including all containing types
         var typeHierarchy = new ValueListBuilder<string>([null, null, null, null]);
+        var typeVsb = new ValueStringBuilder(stackalloc char[128]);
         var currentType = type;
 
         while (currentType != null)
         {
             if (currentType.IsGenericType)
             {
-                var typeSb = new StringBuilder();
                 var name = currentType.Name;
 
                 var backtickIndex = name.IndexOf('`');
                 if (backtickIndex > 0)
                 {
-#if NET6_0_OR_GREATER
-                    typeSb.Append(name.AsSpan(0, backtickIndex));
-#else
-                    typeSb.Append(name.Substring(0, backtickIndex));
-#endif
+                    typeVsb.Append(name.AsSpan(0, backtickIndex));
                 }
                 else
                 {
-                    typeSb.Append(name);
+                    typeVsb.Append(name);
                 }
 
                 // Add the generic type arguments
                 var genericArgs = currentType.GetGenericArguments();
-                typeSb.Append('<');
+                typeVsb.Append('<');
                 for (var i = 0; i < genericArgs.Length; i++)
                 {
                     if (i > 0)
                     {
-                        typeSb.Append(", ");
+                        typeVsb.Append(", ");
                     }
                     // Use the full name for generic arguments to ensure uniqueness
-                    typeSb.Append(genericArgs[i].FullName ?? genericArgs[i].Name);
+                    typeVsb.Append(genericArgs[i].FullName ?? genericArgs[i].Name);
                 }
-                typeSb.Append('>');
+                typeVsb.Append('>');
 
-                typeHierarchy.Append(typeSb.ToString());
+                typeHierarchy.Append(typeVsb.AsSpan().ToString());
+                typeVsb.Length = 0;
             }
             else
             {
@@ -147,6 +144,7 @@ private static void WriteTypeNameWithGenerics(ref ValueStringBuilder vsb, Type t
             vsb.Append(typeHierarchy[i]);
         }
         typeHierarchy.Dispose();
+        typeVsb.Dispose();
     }
 
     private static void WriteTypeWithParameters(ref ValueStringBuilder vsb, ReadOnlySpan<ParameterMetadata> parameterTypes)