Add GenericTypeParameterBuilder implementation and save a generic type into assembly.

src/coreclr/System.Private.CoreLib/src/System/Reflection/Emit/RuntimeTypeBuilder.cs

@@ -491,14 +491,11 @@ internal RuntimeTypeBuilder(
             int[]? interfaceTokens = null;
             if (interfaces != null)
             {
+                interfaceTokens = new int[interfaces.Length + 1];
                 for (i = 0; i < interfaces.Length; i++)
                 {
                     // cannot contain null in the interface list
                     ArgumentNullException.ThrowIfNull(interfaces[i], nameof(interfaces));
-                }
-                interfaceTokens = new int[interfaces.Length + 1];
-                for (i = 0; i < interfaces.Length; i++)
-                {
                     interfaceTokens[i] = m_module.GetTypeTokenInternal(interfaces[i]);
                 }
             }
@@ -1144,15 +1141,18 @@ internal void SetInterfaces(params Type[]? interfaces)
 
         protected override GenericTypeParameterBuilder[] DefineGenericParametersCore(params string[] names)
         {
-            for (int i = 0; i < names.Length; i++)
-                ArgumentNullException.ThrowIfNull(names[i], nameof(names));
-
             if (m_inst != null)
+            {
                 throw new InvalidOperationException();
+            }
 
             m_inst = new RuntimeGenericTypeParameterBuilder[names.Length];
             for (int i = 0; i < names.Length; i++)
-                m_inst[i] = new RuntimeGenericTypeParameterBuilder(new RuntimeTypeBuilder(names[i], i, this));
+            {
+                string name = names[i];
+                ArgumentNullException.ThrowIfNull(name, nameof(names));
+                m_inst[i] = new RuntimeGenericTypeParameterBuilder(new RuntimeTypeBuilder(name, i, this));
+            }
 
             return m_inst;
         }

src/libraries/System.Reflection.Emit/src/System.Reflection.Emit.csproj

@@ -8,6 +8,7 @@
     <Compile Include="System\Reflection\Emit\CustomAttributeWrapper.cs" />
     <Compile Include="System\Reflection\Emit\AssemblyBuilderImpl.cs" />
     <Compile Include="System\Reflection\Emit\FieldBuilderImpl.cs" />
+    <Compile Include="System\Reflection\Emit\GenericTypeParameterBuilderImpl.cs" />
     <Compile Include="System\Reflection\Emit\MethodBuilderImpl.cs" />
     <Compile Include="System\Reflection\Emit\ModuleBuilderImpl.cs" />
     <Compile Include="System\Reflection\Emit\ParameterBuilderImpl.cs" />

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

@@ -0,0 +1,148 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
+
+namespace System.Reflection.Emit
+{
+    internal sealed class GenericTypeParameterBuilderImpl : GenericTypeParameterBuilder
+    {
+        private readonly string _name;
+        private readonly TypeBuilderImpl _type;
+        private readonly int _genParamPosition;
+        private GenericParameterAttributes _genParamAttributes;
+        private bool _isGenericType;
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
+        private Type? _parent;
+
+        internal List<CustomAttributeWrapper>? _customAttributes;
+        internal List<Type>? _interfaces;
+
+        internal GenericTypeParameterBuilderImpl(string name, int genParamPosition, TypeBuilderImpl typeBuilder)
+        {
+            _name = name;
+            _genParamPosition = genParamPosition;
+            _type = typeBuilder;
+            _isGenericType = true;
+        }
+
+        protected override void SetBaseTypeConstraintCore([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] Type? baseTypeConstraint)
+        {
+            _parent = baseTypeConstraint;
+
+            if (_parent != null)
+            {
+                _interfaces ??= new List<Type>();
+                _interfaces.Add(_parent);
+            }
+        }
+
+        protected override void SetCustomAttributeCore(ConstructorInfo con, ReadOnlySpan<byte> binaryAttribute)
+        {
+            _customAttributes ??= new List<CustomAttributeWrapper>();
+            _customAttributes.Add(new CustomAttributeWrapper(con, binaryAttribute));
+        }
+
+        protected override void SetGenericParameterAttributesCore(GenericParameterAttributes genericParameterAttributes) =>
+            _genParamAttributes = genericParameterAttributes;
+
+        protected override void SetInterfaceConstraintsCore(params Type[]? interfaceConstraints)
+        {
+            if (interfaceConstraints != null)
+            {
+                _interfaces ??= new List<Type>(interfaceConstraints.Length);
+                _interfaces.AddRange(interfaceConstraints);
+            }
+        }
+        public override Type[] GetGenericParameterConstraints() =>
+            _interfaces == null ? EmptyTypes : _interfaces.ToArray();
+        public override bool IsGenericTypeParameter => _isGenericType;
+        public override bool IsGenericMethodParameter => !_isGenericType;
+        public override int GenericParameterPosition => _genParamPosition;
+        public override GenericParameterAttributes GenericParameterAttributes => _genParamAttributes;
+        public override string Name => _name;
+        public override Module Module => _type.Module;
+        public override Assembly Assembly => _type.Assembly;
+        public override string? FullName => null;
+        public override string? Namespace => null;
+        public override string? AssemblyQualifiedName => null;
+        public override Type UnderlyingSystemType => this;
+        public override bool IsGenericTypeDefinition => false;
+        public override bool IsGenericType => false;
+        public override bool IsGenericParameter => true;
+        public override bool IsConstructedGenericType => false;
+        public override bool ContainsGenericParameters => _type.ContainsGenericParameters;
+        public override MethodBase? DeclaringMethod => throw new NotImplementedException();
+        public override Type? BaseType => _parent;
+        public override RuntimeTypeHandle TypeHandle => throw new NotSupportedException();
+        public override Guid GUID => throw new NotSupportedException();
+        protected override bool IsArrayImpl() => false;
+        protected override bool IsByRefImpl() => false;
+        protected override bool IsPointerImpl() => false;
+        protected override bool IsPrimitiveImpl() => false;
+        protected override bool IsCOMObjectImpl() => false;
+        protected override bool HasElementTypeImpl() => false;
+        protected override TypeAttributes GetAttributeFlagsImpl() => TypeAttributes.Public;
+        public override Type GetElementType() => throw new NotSupportedException();
+        public override object[] GetCustomAttributes(bool inherit) => throw new NotSupportedException();
+        public override object[] GetCustomAttributes(Type attributeType, bool inherit) => throw new NotSupportedException();
+        public override bool IsDefined(Type attributeType, bool inherit) => throw new NotSupportedException();
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)]
+        protected override ConstructorInfo GetConstructorImpl(BindingFlags bindingAttr, Binder? binder, CallingConventions callConvention, Type[] types, ParameterModifier[]? modifiers) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)]
+        public override ConstructorInfo[] GetConstructors(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods | DynamicallyAccessedMemberTypes.NonPublicMethods)]
+        protected override MethodInfo GetMethodImpl(string name, BindingFlags bindingAttr, Binder? binder, CallingConventions callConvention, Type[]? types, ParameterModifier[]? modifiers) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods | DynamicallyAccessedMemberTypes.NonPublicMethods)]
+        public override MethodInfo[] GetMethods(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicFields | DynamicallyAccessedMemberTypes.NonPublicFields)]
+        public override FieldInfo GetField(string name, BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicFields | DynamicallyAccessedMemberTypes.NonPublicFields)]
+        public override FieldInfo[] GetFields(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.Interfaces)]
+        [return: DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.Interfaces)]
+        public override Type GetInterface(string name, bool ignoreCase) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.Interfaces)]
+        public override Type[] GetInterfaces() => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicEvents | DynamicallyAccessedMemberTypes.NonPublicEvents)]
+        public override EventInfo GetEvent(string name, BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicEvents)]
+        public override EventInfo[] GetEvents() => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicProperties | DynamicallyAccessedMemberTypes.NonPublicProperties)]
+        protected override PropertyInfo GetPropertyImpl(string name, BindingFlags bindingAttr, Binder? binder, Type? returnType, Type[]? types, ParameterModifier[]? modifiers) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicProperties | DynamicallyAccessedMemberTypes.NonPublicProperties)]
+        public override PropertyInfo[] GetProperties(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicNestedTypes | DynamicallyAccessedMemberTypes.NonPublicNestedTypes)]
+        public override Type[] GetNestedTypes(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicNestedTypes | DynamicallyAccessedMemberTypes.NonPublicNestedTypes)]
+        public override Type GetNestedType(string name, BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(TypeBuilderImpl.GetAllMembers)]
+        public override MemberInfo[] GetMember(string name, MemberTypes type, BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        public override InterfaceMapping GetInterfaceMap([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicMethods | DynamicallyAccessedMemberTypes.NonPublicMethods)] Type interfaceType) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicEvents | DynamicallyAccessedMemberTypes.NonPublicEvents)]
+        public override EventInfo[] GetEvents(BindingFlags bindingAttr) => throw new NotSupportedException();
+
+        [DynamicallyAccessedMembers(TypeBuilderImpl.GetAllMembers)]
+        public override MemberInfo[] GetMembers(BindingFlags bindingAttr) => throw new NotSupportedException();
+        [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)]
+        public override object InvokeMember(string name, BindingFlags invokeAttr, Binder? binder, object? target, object?[]? args, ParameterModifier[]? modifiers, CultureInfo? culture, string[]? namedParameters) => throw new NotSupportedException();
+    }
+}