Implement IsByRefLike on the remaining Reflection.Emit Type subclasses

src/libraries/System.Private.CoreLib/src/System/Reflection/Emit/SymbolType.cs

@@ -259,6 +259,8 @@ internal void SetFormat(string format, int curIndex, int length)
 
         public override bool IsTypeDefinition => false;
 
+        public override bool IsByRefLike => false;
+
         public override bool IsSZArray => _rank <= 1 && _isSzArray;
 
         public override Type? GetNullableUnderlyingType() => null;

src/libraries/System.Private.CoreLib/src/System/Reflection/Emit/TypeBuilderInstantiation.cs

@@ -217,6 +217,7 @@ public override Type? BaseType
         protected override TypeAttributes GetAttributeFlagsImpl() { return _genericType.Attributes; }
 
         public override bool IsTypeDefinition => false;
+        public override bool IsByRefLike => _genericType.IsByRefLike;
         public override bool IsSZArray => false;
 
         protected override bool IsArrayImpl() { return false; }

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

@@ -83,6 +83,7 @@ public override Type[] GetGenericParameterConstraints() =>
         public override bool IsGenericType => false;
         public override bool IsGenericParameter => true;
         public override bool IsConstructedGenericType => false;
+        public override bool IsByRefLike => false;
         public override bool ContainsGenericParameters => false;
         public override MethodBase? DeclaringMethod => _type.DeclaringMethod;
         public override Type? BaseType => _parent;

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

@@ -622,6 +622,7 @@ public override Type GetEnumUnderlyingType()
                 throw new ArgumentException(SR.Argument_MustBeEnum);
             }
         }
+        public override bool IsByRefLike => false;
         public override bool IsSZArray => false;
         public override Guid GUID => throw new NotSupportedException();
         public override Type? BaseType => _typeParent;

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

@@ -1010,5 +1010,38 @@ public void TestContainsGenericParametersOnMethodCtorOfConstructedGenericType()
             Assert.False(TypeBuilder.GetConstructor(instantiatedTypeBuilder2, constructorBuilder).ContainsGenericParameters);
             Assert.False(TypeBuilder.GetMethod(instantiatedTypeBuilder2, methodBuilder).ContainsGenericParameters);
         }
+
+        [Fact]
+        public void IsByRefLike_TypeBuilderAndConstructedTypes_ReturnsFalse()
+        {
+            AssemblySaveTools.PopulateAssemblyBuilderAndTypeBuilder(out TypeBuilder type);
+            GenericTypeParameterBuilder[] typeParams = type.DefineGenericParameters("T");
+
+            Type[] types =
+            [
+                type,
+                typeParams[0],
+                type.MakeGenericType(typeof(int)),
+                type.MakeArrayType(),
+                type.MakeArrayType(2),
+                type.MakePointerType(),
+                type.MakeByRefType(),
+                typeParams[0].MakeArrayType(),
+                typeParams[0].MakePointerType(),
+                typeParams[0].MakeByRefType(),
+            ];
+
+            Assert.All(types, t => Assert.False(t.IsByRefLike));
+        }
+
+        [Theory]
+        [InlineData(typeof(Span<>), true)]
+        [InlineData(typeof(ReadOnlySpan<>), true)]
+        [InlineData(typeof(List<>), false)]
+        public void IsByRefLike_RuntimeGenericTypeInstantiatedOverTypeBuilder_MatchesGenericTypeDefinition(Type genericTypeDefinition, bool expected)
+        {
+            AssemblySaveTools.PopulateAssemblyBuilderAndTypeBuilder(out TypeBuilder type);
+            Assert.Equal(expected, genericTypeDefinition.MakeGenericType(type).IsByRefLike);
+        }
     }
 }

src/libraries/System.Reflection.Emit/tests/TypeBuilder/TypeBuilderIsByRefLike.cs

@@ -1,6 +1,7 @@
 // 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 Xunit;
 
 namespace System.Reflection.Emit.Tests
@@ -13,5 +14,36 @@ public void IsByRefLikeReturnsFalse()
             TypeBuilder type = Helpers.DynamicType(TypeAttributes.Public);
             Assert.False(type.IsByRefLike);
         }
+
+        [Fact]
+        public void IsByRefLike_TypesConstructedFromTypeBuilder_ReturnsFalse()
+        {
+            TypeBuilder type = Helpers.DynamicType(TypeAttributes.Public);
+            GenericTypeParameterBuilder[] typeParams = type.DefineGenericParameters("T");
+
+            Type[] constructedTypes =
+            [
+                type.MakeGenericType(typeof(int)),
+                type.MakeArrayType(),
+                type.MakeArrayType(2),
+                type.MakePointerType(),
+                type.MakeByRefType(),
+                typeParams[0].MakeArrayType(),
+                typeParams[0].MakePointerType(),
+                typeParams[0].MakeByRefType(),
+            ];
+
+            Assert.All(constructedTypes, t => Assert.False(t.IsByRefLike));
+        }
+
+        [Theory]
+        [InlineData(typeof(Span<>), true)]
+        [InlineData(typeof(ReadOnlySpan<>), true)]
+        [InlineData(typeof(List<>), false)]
+        public void IsByRefLike_RuntimeGenericTypeInstantiatedOverTypeBuilder_MatchesGenericTypeDefinition(Type genericTypeDefinition, bool expected)
+        {
+            TypeBuilder type = Helpers.DynamicType(TypeAttributes.Public);
+            Assert.Equal(expected, genericTypeDefinition.MakeGenericType(type).IsByRefLike);
+        }
     }
 }