Fix: Using TypeBuilder as generic argument for a parent type throws (#99771)

* Fix: Using TypeBuilder as generic argument for a parent type throws

* No need to branch out for constructed generic parent

* Update method name

Author: buyaa-n

src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/ModuleBuilderImpl.cs

@@ -609,7 +609,7 @@ private static MemberInfo GetOriginalMemberIfConstructedType(MethodBase methodBa
             Type declaringType = methodBase.DeclaringType!;
             if (declaringType.IsConstructedGenericType &&
                 declaringType.GetGenericTypeDefinition() is not TypeBuilderImpl &&
-                !ContainsNotBakedTypeBuilder(declaringType.GetGenericArguments()))
+                !ContainsTypeBuilder(declaringType.GetGenericArguments()))
             {
                 return declaringType.GetGenericTypeDefinition().GetMemberWithSameMetadataDefinitionAs(methodBase);
             }
@@ -883,19 +883,19 @@ private static int GetTokenForHandle(EntityHandle handle)
 
         private EntityHandle GetHandleForMember(MemberInfo member)
         {
-            if (IsConstructedFromNotBakedTypeBuilder(member.DeclaringType!))
+            if (IsConstructedFromTypeBuilder(member.DeclaringType!))
             {
                 return default;
             }
 
             return GetMemberReferenceHandle(member);
         }
 
-        private static bool IsConstructedFromNotBakedTypeBuilder(Type type) => type.IsConstructedGenericType &&
+        private static bool IsConstructedFromTypeBuilder(Type type) => type.IsConstructedGenericType &&
             (type.GetGenericTypeDefinition() is TypeBuilderImpl ||
-             ContainsNotBakedTypeBuilder(type.GetGenericArguments()));
+             ContainsTypeBuilder(type.GetGenericArguments()));
 
-        private static bool ContainsNotBakedTypeBuilder(Type[] genericArguments)
+        internal static bool ContainsTypeBuilder(Type[] genericArguments)
         {
             foreach (Type type in genericArguments)
             {
@@ -904,7 +904,7 @@ private static bool ContainsNotBakedTypeBuilder(Type[] genericArguments)
                     return true;
                 }
 
-                if (IsConstructedFromNotBakedTypeBuilder(type))
+                if (IsConstructedFromTypeBuilder(type))
                 {
                     return true;
                 }
@@ -925,7 +925,7 @@ internal EntityHandle TryGetTypeHandle(Type type)
                 return eb._typeBuilder._handle;
             }
 
-            if (IsConstructedFromNotBakedTypeBuilder(type))
+            if (IsConstructedFromTypeBuilder(type))
             {
                 return default;
             }
@@ -954,20 +954,20 @@ internal EntityHandle TryGetMethodHandle(MethodInfo method)
                 return mb._handle;
             }
 
-            if (IsConstructedMethodFromNotBakedMethodBuilder(method) ||
-                IsArrayMethodFromNotBakedTypeBuilder(method))
+            if (IsConstructedFromMethodBuilderOrTypeBuilder(method) ||
+                IsArrayMethodTypeIsTypeBuilder(method))
             {
                 return default;
             }
 
             return GetHandleForMember(method);
         }
 
-        private static bool IsArrayMethodFromNotBakedTypeBuilder(MethodInfo method) => method is ArrayMethod arrayMethod &&
-            arrayMethod.DeclaringType!.GetElementType() is TypeBuilderImpl tb && tb._handle == default;
+        private static bool IsArrayMethodTypeIsTypeBuilder(MethodInfo method) => method is ArrayMethod arrayMethod &&
+            arrayMethod.DeclaringType!.GetElementType() is TypeBuilderImpl;
 
-        private static bool IsConstructedMethodFromNotBakedMethodBuilder(MethodInfo method) => method.IsConstructedGenericMethod &&
-            (method.GetGenericMethodDefinition() is MethodBuilderImpl mb && mb._handle == default || ContainsNotBakedTypeBuilder(method.GetGenericArguments()));
+        private static bool IsConstructedFromMethodBuilderOrTypeBuilder(MethodInfo method) => method.IsConstructedGenericMethod &&
+            (method.GetGenericMethodDefinition() is MethodBuilderImpl || ContainsTypeBuilder(method.GetGenericArguments()));
 
         internal EntityHandle TryGetMethodHandle(MethodInfo method, Type[] optionalParameterTypes)
         {
@@ -982,7 +982,7 @@ internal EntityHandle TryGetMethodHandle(MethodInfo method, Type[] optionalParam
                 return mb._handle;
             }
 
-            if (IsConstructedMethodFromNotBakedMethodBuilder(method))
+            if (IsConstructedFromMethodBuilderOrTypeBuilder(method))
             {
                 return default;
             }

src/libraries/System.Reflection.Emit/src/System/Reflection/Emit/TypeBuilderImpl.cs

@@ -211,9 +211,11 @@ private ConstructorBuilderImpl DefineDefaultConstructorInternal(MethodAttributes
         {
             // Get the parent class's default constructor and add it to the IL
             ConstructorInfo? con;
-            if (_typeParent!.IsConstructedGenericType && _typeParent.GetGenericTypeDefinition() is TypeBuilderImpl typeBuilder)
+            if (_typeParent!.IsConstructedGenericType &&
+                (_typeParent.GetGenericTypeDefinition() is TypeBuilderImpl || ModuleBuilderImpl.ContainsTypeBuilder(_typeParent.GetGenericArguments())))
             {
-                con = GetConstructor(_typeParent, typeBuilder.GetConstructor(
+                // When TypeBuilder involved need to construct the parent constructor using TypeBuilder.GetConstructor() static method
+                con = GetConstructor(_typeParent, _typeParent.GetGenericTypeDefinition().GetConstructor(
                     BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, EmptyTypes, null)!);
             }
             else

src/libraries/System.Reflection.Emit/tests/PersistedAssemblyBuilder/AssemblySaveTypeBuilderTests.cs

@@ -649,6 +649,23 @@ public void MethodBuilderGetParametersReturnParameterTest()
             Assert.Null(method3.ReturnParameter.Name);
             Assert.True(method3.ReturnParameter.IsRetval);
         }
+
+        public class BaseType<T> { }
+
+        [Fact]
+        public void GenericTypeWithTypeBuilderGenericParameter_UsedAsParent()
+        {
+            PersistedAssemblyBuilder ab = AssemblySaveTools.PopulateAssemblyBuilderAndTypeBuilder(out TypeBuilder typeBuilder);
+
+            Type type = typeBuilder.CreateType();
+            var baseType = typeof(BaseType<>).GetGenericTypeDefinition().MakeGenericType(type);
+
+            var typeBuilder2 = ab.GetDynamicModule("MyModule")
+                .DefineType("TestService", TypeAttributes.Public | TypeAttributes.Class, baseType);
+            typeBuilder2.CreateType();
+
+            Assert.NotNull(type.GetConstructor(Type.EmptyTypes)); // Default constructor created
+        }
     }
 
     // Test Types