Fix trim warnings in 'AdaptiveFromAbiHelper'

src/WinRT.Runtime/Projections/Bindable.net5.cs

@@ -370,9 +370,11 @@ internal static class IBindableVectorView_Delegates
 }
 
 namespace ABI.System.Collections
-{
+{
  using global::Microsoft.UI.Xaml.Interop;
- using global::System;
+ using global::System;
+ using global::System.Diagnostics.CodeAnalysis;
+ using global::System.Reflection;
  using global::System.Runtime.CompilerServices;
 
 #if EMBED
@@ -396,22 +398,82 @@ internal unsafe interface IEnumerable : global::System.Collections.IEnumerable,
 #pragma warning disable CA2257 // This member is a type (so it cannot be invoked)
  public sealed class AdaptiveFromAbiHelper : FromAbiHelper, global::System.Collections.IEnumerable
 #pragma warning restore CA2257
- {
- private readonly Func<IWinRTObject, global::System.Collections.IEnumerator> _enumerator;
+ {
+ /// <summary>
+ /// The cached <see cref="IEnumerable{T}.GetEnumerator"/> method.
+ /// </summary>
+ private static readonly MethodInfo EnumerableOfTGetEnumerator = typeof(IEnumerable<>).GetMethod("GetEnumerator");
+
+#if NET8_0_OR_GREATER
+ private readonly MethodInvoker _enumerator;
+#else
+ private readonly MethodInfo _enumerator;
+#endif
 
  public AdaptiveFromAbiHelper(Type runtimeType, IWinRTObject winRTObject)
  :base(winRTObject)
  {
- Type enumGenericType = (runtimeType.IsGenericType && runtimeType.GetGenericTypeDefinition() == typeof(global::System.Collections.Generic.IEnumerable<>)) ? 
- runtimeType : runtimeType.GetInterface("System.Collections.Generic.IEnumerable`1");
- if(enumGenericType != null)
- {
- var getEnumerator = enumGenericType.GetMethod("GetEnumerator");
- _enumerator = (IWinRTObject obj) => (global::System.Collections.IEnumerator)getEnumerator.Invoke(obj, null);
+ Type enumGenericType;
+
+ // First, look for and get the IEnumerable<> interface implemented by this type, if one exists. The scenario is, imagine you
+ // got an 'IList<string>' from somewhere, and then you use LINQ with it. What LINQ does is it converts both to object. Then
+ // it does a cast to 'IEnumerable'. At this point, you are trying an IDIC cast for 'IEnumerable' and asking the IDIC 'IEnumerable'
+ // interface to handle it. The question to answer is, what version of 'IEnumerable' is it. Is it the one provided by 'IList<string>'
+ // or is it the one that maps to 'IBindableIterable'. We actually don't know at this point which one to use, especially given the
+ // 'IBindableIterable' interface may not even be implemented on the native object, as it was an 'IList<string>' originally. This is
+ // also why we can't just check whether the object implements 'IEnumerable' and just call 'GetEnumerator()' on that.
+ if (runtimeType.IsGenericType && runtimeType.GetGenericTypeDefinition() == typeof(IEnumerable<>))
+ {
+ enumGenericType = runtimeType;
  }
+ else
+ {
+ [SuppressMessage("Trimming", "IL2070", Justification =
+ """
+ 'SomeType.GetInterfaces().Any(t => t.GetGenericTypeDefinition() == typeof(IEnumerable<>)' is safe,
+ provided you obtained someType from something like an analyzable 'Type.GetType' or 'object.GetType'
+ (i.e. it is safe when the type you're asking about can exist on the GC heap as allocated).
+ """)]
+ [MethodImpl(MethodImplOptions.NoInlining)]
+ static Type GetEnumerableOfTInterface(Type runtimeType)
+ {
+ foreach (Type interfaceType in runtimeType.GetInterfaces())
+ {
+ if (interfaceType.IsGenericType && interfaceType.GetGenericTypeDefinition() == typeof(IEnumerable<>))
+ {
+ return interfaceType;
+ }
+ }
+
+ return null;
+ }
+
+ enumGenericType = GetEnumerableOfTInterface(runtimeType);
+ }
+
+ var methodInfo = (MethodInfo)enumGenericType?.GetMemberWithSameMetadataDefinitionAs(EnumerableOfTGetEnumerator);
+
+#if NET8_0_OR_GREATER
+ _enumerator = methodInfo is null ? null : MethodInvoker.Create(methodInfo);
+#else
+ _enumerator = methodInfo;
+#endif
  }
 
- public override global::System.Collections.IEnumerator GetEnumerator() => _enumerator != null ? _enumerator(_winrtObject) : base.GetEnumerator();
+ public override IEnumerator GetEnumerator()
+ {
+ if (_enumerator is not null)
+ {
+ // The method returns IEnumerator<>, which implements IEnumerator
+#if NET8_0_OR_GREATER
+ return Unsafe.As<IEnumerator>(_enumerator.Invoke(_winrtObject));
+#else
+ return Unsafe.As<IEnumerator>(_enumerator.Invoke(_winrtObject, null));
+#endif
+ }
+
+ return base.GetEnumerator();
+ }
  }
 
 #pragma warning disable CA2257 // This member is a type (so it cannot be invoked)
@@ -547,7 +609,7 @@ private static FromAbiHelper _AbiHelper(IWinRTObject _this)
  internal
 #else
  public 
-#endif 
+#endif
  static class IEnumerable_Delegates
  {
  public unsafe delegate int First_0(IntPtr thisPtr, IntPtr* result);

src/WinRT.Runtime/TypeNameSupport.cs

@@ -196,7 +196,7 @@ private static Type FindTypeByNameCore(string runtimeClassName, Type[] genericTy
  return null;
 
 #if NET
- [UnconditionalSuppressMessage("AOT", "IL3050", Justification = "Calls to MakeGenericType are done with reference types")]
+ [UnconditionalSuppressMessage("AOT", "IL3050", Justification = "Calls to MakeGenericType are done with reference types.")]
 #endif
  static Type ResolveGenericType(Type resolvedType, Type[] genericTypes, string runtimeClassName)
  {