Suppress trim and AOT diagnostics in Dapper fallback paths (#2233)

Dapper/DefaultTypeMap.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Reflection;
 
@@ -33,6 +34,7 @@ namespace Dapper
 
             static MethodInfo Throw(PropertyInfo propertyInfo) => throw new InvalidOperationException("Property setting not found for: " + propertyInfo?.Name);
         }
+        [UnconditionalSuppressMessage("Trimming", "IL2075", Justification = "The property was obtained from the mapped type and its setter must be preserved whenever the property is preserved.")]
         internal static MethodInfo? GetPropertySetter(PropertyInfo propertyInfo, Type type)
         {
             if (propertyInfo.DeclaringType == type) return propertyInfo.GetSetMethod(true);
@@ -46,6 +48,7 @@ namespace Dapper
                    null)!.GetSetMethod(true);
         }
 
+        [UnconditionalSuppressMessage("Trimming", "IL2070", Justification = "Dapper's runtime mapping contract requires the mapped type's properties to be preserved.")]
         internal static List<PropertyInfo> GetSettableProps(Type t)
         {
             return t
@@ -54,6 +57,7 @@ namespace Dapper
                   .ToList();
         }
 
+        [UnconditionalSuppressMessage("Trimming", "IL2070", Justification = "Dapper's runtime mapping contract requires the mapped type's fields to be preserved.")]
         private static FieldInfo[] GetSettableFields(Type t)
         {
             return t.GetFields(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

Dapper/NRT.cs

@@ -1,6 +1,14 @@
 #if !NET5_0_OR_GREATER
 namespace System.Diagnostics.CodeAnalysis
 {
+    [AttributeUsage(AttributeTargets.All, Inherited = false, AllowMultiple = true)]
+    internal sealed class UnconditionalSuppressMessageAttribute : Attribute
+    {
+        public UnconditionalSuppressMessageAttribute(string category, string checkId) { }
+
+        public string? Justification { get; set; }
+    }
+
     [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
     internal sealed class NotNullWhenAttribute : Attribute
     {

Dapper/SqlDataRecordListTVPParameter.cs

@@ -2,6 +2,7 @@
 using System.Collections;
 using System.Collections.Generic;
 using System.Data;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Reflection;
 using System.Reflection.Emit;
@@ -64,6 +65,8 @@ namespace Dapper
             }
         }
 
+        [UnconditionalSuppressMessage("Trimming", "IL2070", Justification = "The provider parameter type is only known at runtime and must preserve its public properties.")]
+        [UnconditionalSuppressMessage("Aot", "IL3050", Justification = "This fallback is only used for provider-specific structured parameters and is not supported by Dapper's AOT interceptors.")]
         static Action<IDbDataParameter, string?> CreateFor(Type type, string nameProperty, int sqlDbType)
         {
             var name = type.GetProperty(nameProperty, BindingFlags.Public | BindingFlags.Instance);

Dapper/SqlMapper.cs

@@ -365,6 +365,7 @@ namespace Dapper
             AddTypeHandlerCore(type, handler, true); // do not allow suppress clone
         }
 
+        [UnconditionalSuppressMessage("Aot", "IL3050", Justification = "Runtime type-handler registration requires the caller to statically root the corresponding TypeHandlerCache<T> instantiation.")]
         private static void AddTypeHandlerCore(Type type, ITypeHandler? handler, bool clone)
         {
             if (type is null) throw new ArgumentNullException(nameof(type));
@@ -458,6 +459,7 @@ namespace Dapper
         [Obsolete(ObsoleteInternalUsageOnly, false)]
         [Browsable(false)]
         [EditorBrowsable(EditorBrowsableState.Never)]
+        [UnconditionalSuppressMessage("Aot", "IL3050", Justification = "Runtime generic construction is limited to the optional SQL data-record handler path, which is not supported by Dapper's AOT interceptors.")]
         public static DbType? LookupDbType(Type type, string name, bool demand, out ITypeHandler? handler)
         {
             handler = null;
@@ -2554,6 +2556,8 @@ namespace Dapper
                                                        && type.FullName?.StartsWith("System.ValueTuple`", StringComparison.Ordinal) == true)
                                                        || (type is not null && IsValueTuple(Nullable.GetUnderlyingType(type)));
 
+        [UnconditionalSuppressMessage("Trimming", "IL2075", Justification = "The runtime parameter generator requires the parameter object's public properties and constructors to be preserved.")]
+        [UnconditionalSuppressMessage("Aot", "IL3050", Justification = "This runtime parameter generator is a fallback for non-intercepted calls and is not used by generated AOT code.")]
         internal static Action<IDbCommand, object?> CreateParamInfoGenerator(Identity identity, bool checkForDuplicates, bool removeUnused, IList<LiteralToken> literals)
         {
             Type type = identity.ParametersType!;

Dapper/TypeExtensions.cs

@@ -1,10 +1,12 @@
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
 
 namespace Dapper
 {
     internal static class TypeExtensions
     {
+        [UnconditionalSuppressMessage("Trimming", "IL2070", Justification = "All callers use framework types whose public methods are preserved.")]
         public static MethodInfo? GetPublicInstanceMethod(this Type type, string name, Type[] types)
             => type.GetMethod(name, BindingFlags.Instance | BindingFlags.Public, null, types, null);
     }