support ignoring types globally

Author: lofcz

FastCloner.Tests/IgnoredTypesTests.cs

@@ -1989,6 +1989,57 @@ public bool HasPropertyChangedSubscribers()
         }
     }
 
+    struct ClonerIgnoreStructTest
+    {
+        [FastClonerIgnore]
+        public int MyInt;
+    }
+    
+    struct ClonerIgnoreStructTestNullable
+    {
+        [FastClonerIgnore]
+        public int? MyInt;
+    }
+
+    [Test]
+    public void CloneSimpleInt()
+    {
+        int i = 42.DeepClone();
+        Assert.That(i, Is.EqualTo(42));
+    }
+    
+    [Test]
+    public void StructMembersIgnoreNullable()
+    {
+        // Arrange
+        ClonerIgnoreStructTestNullable inst = new ClonerIgnoreStructTestNullable
+        {
+            MyInt = 49
+        };
+
+        // Act
+        ClonerIgnoreStructTestNullable cloned = inst.DeepClone();
+
+        // Assert
+        Assert.That(cloned.MyInt, Is.EqualTo(null), "Should ignore the field");
+    }
+    
+    [Test]
+    public void StructMembersIgnore()
+    {
+        // Arrange
+        ClonerIgnoreStructTest inst = new ClonerIgnoreStructTest
+        {
+            MyInt = 49
+        };
+
+        // Act
+        ClonerIgnoreStructTest cloned = inst.DeepClone();
+
+        // Assert
+        Assert.That(cloned.MyInt, Is.EqualTo(0), "Should ignore the field");
+    }
+
     [Test]
     public void EventPropertyNotifyChangedIgnore()
     {

FastCloner.Tests/SpecialCaseTests.cs

@@ -7,9 +7,7 @@ internal static class ClonerToExprGenerator
 {
     internal static object GenerateClonerInternal(Type realType, bool isDeepClone)
     {
-        if (realType.IsValueType())
-            throw new InvalidOperationException("Operation is valid only for reference types");
-        return GenerateProcessMethod(realType, isDeepClone);
+        return realType.IsValueType() ? throw new InvalidOperationException("Operation is valid only for reference types") : GenerateProcessMethod(realType, isDeepClone);
     }
 
     private static object GenerateProcessMethod(Type type, bool isDeepClone)

FastCloner/Code/ClonerToExprGenerator.cs

@@ -5,6 +5,13 @@ namespace FastCloner.Code;
 
 internal static class FastClonerCache
 {
+    internal static readonly ConcurrentDictionary<Type, bool> AlwaysIgnoredTypes = [];
+
+    internal static bool IsTypeIgnored(Type type)
+    {
+        return AlwaysIgnoredTypes.TryGetValue(type, out _);
+    }
+    
     private static readonly ClrCache<object?> classCache = new ClrCache<object?>();
     private static readonly ClrCache<object?> structCache = new ClrCache<object?>();
     private static readonly ClrCache<object> deepClassToCache = new ClrCache<object>();
@@ -14,7 +21,8 @@ internal static class FastClonerCache
     private static readonly ClrCache<Dictionary<string, Type>> ignoredEventInfoCache = new ClrCache<Dictionary<string, Type>>();
     private static readonly ClrCache<List<MemberInfo>> allMembersCache = new ClrCache<List<MemberInfo>>();
     private static readonly GenericClrCache<MemberInfo, bool> memberIgnoreStatusCache = new GenericClrCache<MemberInfo, bool>();
-    
+    private static readonly ClrCache<bool> typeContainsIgnoredMembersCache = new ClrCache<bool>();
+
     public static object? GetOrAddField(Type type, Func<Type, object?> valueFactory) => fieldCache.GetOrAdd(type, valueFactory);
     public static object? GetOrAddClass(Type type, Func<Type, object?> valueFactory) => classCache.GetOrAdd(type, valueFactory);
     public static object? GetOrAddStructAsObject(Type type, Func<Type, object?> valueFactory) => structCache.GetOrAdd(type, valueFactory);
@@ -24,6 +32,10 @@ internal static class FastClonerCache
     public static Dictionary<string, Type> GetOrAddIgnoredEventInfo(Type type, Func<Type, Dictionary<string, Type>> valueFactory) => ignoredEventInfoCache.GetOrAdd(type, valueFactory);
     public static List<MemberInfo> GetOrAddAllMembers(Type type, Func<Type, List<MemberInfo>> valueFactory) => allMembersCache.GetOrAdd(type, valueFactory);
     public static bool GetOrAddMemberIgnoreStatus(MemberInfo memberInfo, Func<MemberInfo, bool> valueFactory) => memberIgnoreStatusCache.GetOrAdd(memberInfo, valueFactory);
+    public static bool GetOrAddTypeContainsIgnoredMembers(Type type, Func<Type, bool> valueFactory)
+    {
+        return type.IsValueType && typeContainsIgnoredMembersCache.GetOrAdd(type, valueFactory);
+    }
 
     /// <summary>
     /// Clears the FastCloner cached reflection metadata.