[Trimming] Enable trimming and AOT analyzers in Core

src/Compatibility/Core/src/Windows/FrameworkElementExtensions.cs

@@ -82,7 +82,9 @@ static DependencyProperty GetForegroundProperty(FrameworkElement element)
 			DependencyProperty foregroundProperty;
 			if (!ForegroundProperties.Value.TryGetValue(type, out foregroundProperty))
 			{
-				FieldInfo field = ReflectionExtensions.GetFields(type).FirstOrDefault(f => f.Name == "ForegroundProperty");
+#pragma warning disable IL2075 // The Compatibility assembly is not trimmable
+				FieldInfo field = type.GetField("ForegroundProperty", BindingFlags.Public | BindingFlags.Static | BindingFlags.FlattenHierarchy);
+#pragma warning restore IL2075
 				if (field == null)
 					throw new ArgumentException("type is not a Foregroundable type");
 

src/Controls/src/Core/BindablePropertyConverter.cs

@@ -113,8 +113,8 @@ static Type GetControlType(string typeName)
 		BindableProperty ConvertFrom(Type type, string propertyName, IXmlLineInfo lineinfo)
 		{
 			string name = propertyName + "Property";
-			FieldInfo bpinfo = type.GetField(fi => fi.Name == name && fi.IsStatic && fi.IsPublic && fi.FieldType == typeof(BindableProperty));
-			if (bpinfo == null)
+			FieldInfo bpinfo = type.GetField(name, BindingFlags.Public | BindingFlags.Static | BindingFlags.FlattenHierarchy);
+			if (bpinfo == null || bpinfo.FieldType != typeof(BindableProperty))
 				throw new XamlParseException($"Can't resolve {name} on {type.Name}", lineinfo);
 			var bp = bpinfo.GetValue(null) as BindableProperty;
 			var isObsolete = bpinfo.GetCustomAttribute<ObsoleteAttribute>() != null;

src/Core/src/Core.csproj

@@ -11,6 +11,14 @@
     <NoWarn>$(NoWarn);CS1591;RS0041;RS0026;RS0027</NoWarn>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetFramework)' != 'netstandard2.0' and '$(TargetFramework)' != 'netstandard2.1'">
+    <EnableTrimAnalyzer>true</EnableTrimAnalyzer>
+    <EnableAotAnalyzer>true</EnableAotAnalyzer>
+    <EnableSingleFileAnalyzer>true</EnableSingleFileAnalyzer>
+    <!-- TODO: Remove once XamlTypeInfo.g.cs generates trimming-friendly code -->
+    <NoWarn Condition="$(TargetFramework.Contains('-windows'))">$(NoWarn);IL2059</NoWarn>
+  </PropertyGroup>
+
   <PropertyGroup>
     <!-- NuGet package information -->
     <IsPackable>true</IsPackable>

src/Core/src/Hosting/ImageSources/IImageSourceServiceProvider.cs

@@ -1,6 +1,7 @@
 #nullable enable
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 
 namespace Microsoft.Maui
 {
@@ -12,15 +13,20 @@ public interface IImageSourceServiceProvider : IServiceProvider
 
 #if !NETSTANDARD
 		[Obsolete("Use GetImageSourceService instead.")]
+		[RequiresDynamicCode("The GetImageSourceServiceType method is not AOT compatible. Use GetImageSourceService instead.")]
+		[RequiresUnreferencedCode("The GetImageSourceServiceType method is not trimming compatible. Use GetImageSourceService instead.")]
 		Type GetImageSourceServiceType(Type imageSource) => throw new NotImplementedException();
 
 		[Obsolete("Use GetImageSourceService instead.")]
+		[RequiresUnreferencedCode("The GetImageSourceType method is not trimming compatible. Use GetImageSourceService instead.")]
 		Type GetImageSourceType(Type imageSource) => throw new NotImplementedException();
 #else
 		[Obsolete("Use GetImageSourceService instead.")]
+		[RequiresUnreferencedCode("The GetImageSourceType method is not trimming compatible. Use GetImageSourceService instead.")]
 		Type GetImageSourceServiceType(Type imageSource);
 
 		[Obsolete("Use GetImageSourceService instead.")]
+		[RequiresUnreferencedCode("The GetImageSourceType method is not trimming compatible. Use GetImageSourceService instead.")]
 		Type GetImageSourceType(Type imageSource);
 #endif
 	}

src/Core/src/Hosting/ImageSources/ImageSourceServiceProvider.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.Collections.Concurrent;
+using System.Diagnostics.CodeAnalysis;
 using Microsoft.Maui.Hosting.Internal;
 
 namespace Microsoft.Maui.Hosting
@@ -31,37 +32,54 @@ public ImageSourceServiceProvider(IImageSourceServiceCollection collection, ISer
 			return (IImageSourceService?)GetService(imageSourceService);
 		}
 
-		public Type GetImageSourceServiceType(Type imageSource) =>
-			_serviceCache.GetOrAdd(imageSource, type =>
+#if !NETSTANDARD
+		[RequiresDynamicCode("The GetImageSourceServiceType method is not AOT compatible. Use GetImageSourceService instead.")]
+#endif
+		[RequiresUnreferencedCode("The GetImageSourceServiceType method is not trimming compatible. Use GetImageSourceService instead.")]
+		public Type GetImageSourceServiceType(Type imageSource)
+		{
+			return _serviceCache.GetOrAdd(imageSource, CreateImageSourceServiceTypeCacheEntry);
+
+			Type CreateImageSourceServiceTypeCacheEntry(Type type)
 			{
 				var genericConcreteType = ImageSourceServiceType.MakeGenericType(type);
 
 				if (genericConcreteType != null && InternalCollection.TryGetService(genericConcreteType, out _))
+				{
 					return genericConcreteType;
+				}
 
 				return ImageSourceServiceType.MakeGenericType(GetImageSourceType(type));
-			});
-
-		public Type GetImageSourceType(Type imageSource) =>
-			_imageSourceCache.GetOrAdd(imageSource, CreateImageSourceTypeCacheEntry);
+			}
+		}
 
-		Type CreateImageSourceTypeCacheEntry(Type type)
+		[RequiresUnreferencedCode("The GetImageSourceType method is not trimming compatible. Use GetImageSourceService instead.")]
+		public Type GetImageSourceType(Type imageSource)
 		{
-			if (type.IsInterface)
-			{
-				if (type.GetInterface(ImageSourceInterface) != null)
-					return type;
-			}
-			else
+			return _imageSourceCache.GetOrAdd(imageSource, CreateImageSourceTypeCacheEntry);
+
+			Type CreateImageSourceTypeCacheEntry(Type type)
 			{
-				foreach (var directInterface in type.GetInterfaces())
+				if (type.IsInterface)
 				{
-					if (directInterface.GetInterface(ImageSourceInterface) != null)
-						return directInterface;
+					if (type.GetInterface(ImageSourceInterface) != null)
+					{
+						return type;
+					}
+				}
+				else
+				{
+					foreach (var directInterface in type.GetInterfaces())
+					{
+						if (directInterface.GetInterface(ImageSourceInterface) != null)
+						{
+							return directInterface;
+						}
+					}
 				}
-			}
 
-			throw new InvalidOperationException($"Unable to find the image source type because none of the interfaces on {type.Name} were derived from {nameof(IImageSource)}.");
+				throw new InvalidOperationException($"Unable to find the image source type because none of the interfaces on {type.Name} were derived from {nameof(IImageSource)}.");
+			}
 		}
 	}
 }

src/Core/src/HotReload/HotReloadExtensions.cs

@@ -1,6 +1,7 @@
 #nullable enable
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Reflection;
 using Microsoft.Maui.Hosting;
@@ -34,20 +35,24 @@ public static void CheckHandlers(this IView? view)
 			}
 		}
 
-		public static List<MethodInfo> GetOnHotReloadMethods(this Type type) => getOnHotReloadMethods(type).Distinct(new ReflectionMethodComparer()).ToList();
-
-		static IEnumerable<MethodInfo> getOnHotReloadMethods(Type type, bool isSubclass = false)
+		[RequiresUnreferencedCode("Hot Reload is not trim compatible")]
+		public static List<MethodInfo> GetOnHotReloadMethods(this Type type)
 		{
-			var flags = BindingFlags.Static | BindingFlags.FlattenHierarchy | BindingFlags.Public | BindingFlags.NonPublic;
-			if (isSubclass)
-				flags = BindingFlags.Static | BindingFlags.NonPublic;
-			var foos = type.GetMethods(flags).Where(x => x.GetCustomAttributes(typeof(OnHotReloadAttribute), true).Length > 0).ToList();
-			foreach (var foo in foos)
-				yield return foo;
-
-			if (type.BaseType != null)
-				foreach (var foo in getOnHotReloadMethods(type.BaseType, true))
+			return getOnHotReloadMethods(type).Distinct(new ReflectionMethodComparer()).ToList();
+
+			static IEnumerable<MethodInfo> getOnHotReloadMethods(Type type, bool isSubclass = false)
+			{
+				var flags = BindingFlags.Static | BindingFlags.FlattenHierarchy | BindingFlags.Public | BindingFlags.NonPublic;
+				if (isSubclass)
+					flags = BindingFlags.Static | BindingFlags.NonPublic;
+				var foos = type.GetMethods(flags).Where(x => x.GetCustomAttributes(typeof(OnHotReloadAttribute), true).Length > 0).ToList();
+				foreach (var foo in foos)
 					yield return foo;
+
+				if (type.BaseType != null)
+					foreach (var foo in getOnHotReloadMethods(type.BaseType, true))
+						yield return foo;
+			}
 		}
 
 		class ReflectionMethodComparer : IEqualityComparer<MethodInfo>

src/Core/src/HotReload/HotReloadHelper.cs

@@ -2,6 +2,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Reflection;
 using Microsoft.Extensions.DependencyInjection;
@@ -97,6 +98,11 @@ static void TransferState(IHotReloadableView oldView, IView newView)
 		static Dictionary<string, Type> replacedViews = new(StringComparer.Ordinal);
 		static Dictionary<IHotReloadableView, object[]> currentViews = new Dictionary<IHotReloadableView, object[]>();
 		static Dictionary<string, List<KeyValuePair<Type, Type>>> replacedHandlers = new(StringComparer.Ordinal);
+
+		[RequiresUnreferencedCode("Hot Reload is not trim compatible")]
+#if !NETSTANDARD
+		[RequiresDynamicCode("Hot Reload is not AOT compatible")]
+#endif
 		public static void RegisterReplacedView(string oldViewType, Type newViewType)
 		{
 			if (!IsSupported || !IsEnabled)
@@ -145,17 +151,15 @@ public static void RegisterReplacedView(string oldViewType, Type newViewType)
 				}
 			}
 
-		}
-
-
-		static void RegisterHandler(KeyValuePair<Type, Type> pair, Type newHandler)
-		{
-			_ = HandlerService ?? throw new ArgumentNullException(nameof(HandlerService));
-			var view = pair.Key;
-			var newType = newHandler;
-			if (pair.Value.IsGenericType)
-				newType = pair.Value.GetGenericTypeDefinition().MakeGenericType(newHandler);
-			HandlerService.AddHandler(view, newType);
+			static void RegisterHandler(KeyValuePair<Type, Type> pair, Type newHandler)
+			{
+				_ = HandlerService ?? throw new ArgumentNullException(nameof(HandlerService));
+				var view = pair.Key;
+				var newType = newHandler;
+				if (pair.Value.IsGenericType)
+					newType = pair.Value.GetGenericTypeDefinition().MakeGenericType(newHandler);
+				HandlerService.AddHandler(view, newType);
+			}
 		}
 
 		public static void TriggerReload()
@@ -179,6 +183,10 @@ public static void TriggerReload()
 			}
 		}
 		#region Metadata Update Handler
+		[RequiresUnreferencedCode("Hot Reload is not trim compatible")]
+#if !NETSTANDARD
+		[RequiresDynamicCode("Hot Reload is not AOT compatible")]
+#endif
 		public static void UpdateApplication(Type[] types)
 		{
 			IsEnabled = true;

src/Core/src/ImageSources/FileImageSourceService/FileImageSourceService.Tizen.cs

@@ -52,7 +52,7 @@ static string GetPath(string res)
 				return res;
 			}
 
-			foreach (AppFW.ResourceManager.Category category in Enum.GetValues(typeof(AppFW.ResourceManager.Category)))
+			foreach (AppFW.ResourceManager.Category category in Enum.GetValues<AppFW.ResourceManager.Category>())
 			{
 				foreach (var file in new[] { res, res + ".jpg", res + ".png", res + ".gif" })
 				{

src/Core/src/Platform/ReflectionExtensions.cs

@@ -1,24 +1,12 @@
 #nullable enable
 using System;
-using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Reflection;
 
 namespace Microsoft.Maui.Platform
 {
 	internal static class ReflectionExtensions
 	{
-		public static FieldInfo? GetField(this Type type, Func<FieldInfo, bool> predicate)
-		{
-			return GetFields(type).FirstOrDefault(predicate);
-		}
-
-		public static IEnumerable<FieldInfo> GetFields(this Type type)
-		{
-			return GetParts(type, i => i.DeclaredFields);
-		}
-
 		internal static object[]? GetCustomAttributesSafe(this Assembly assembly, Type attrType)
 		{
 			try
@@ -38,17 +26,5 @@ public static bool IsInstanceOfType(this Type self, object o)
 		{
 			return self.IsAssignableFrom(o.GetType());
 		}
-
-		static IEnumerable<T> GetParts<T>(Type type, Func<TypeInfo, IEnumerable<T>> selector)
-		{
-			Type? t = type;
-			while (t != null)
-			{
-				TypeInfo ti = t.GetTypeInfo();
-				foreach (T f in selector(ti))
-					yield return f;
-				t = ti.BaseType;
-			}
-		}
 	}
 }