Fix the generated C# for fields of type function pointer

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/Generator/Generators/CSharp/CSharpTypePrinter.cs

@@ -157,42 +157,6 @@ namespace CppSharp.Generators.CSharp
             return base.VisitBuiltinType(builtin, quals);
         }
 
-        public override TypePrinterResult VisitFunctionType(FunctionType function,
-            TypeQualifiers quals)
-        {
-            var arguments = function.Parameters;
-            var returnType = function.ReturnType;
-            var args = string.Empty;
-
-            PushMarshalKind(MarshalKind.GenericDelegate);
-
-            if (arguments.Count > 0)
-                args = VisitParameters(function.Parameters, hasNames: false).Type;
-
-            PopMarshalKind();
-
-            if (ContextKind != TypePrinterContextKind.Managed)
-                return IntPtrType;
-
-            if (returnType.Type.IsPrimitiveType(PrimitiveType.Void))
-            {
-                if (!string.IsNullOrEmpty(args))
-                    args = string.Format("<{0}>", args);
-                return string.Format("Action{0}", args);
-            }
-
-            if (!string.IsNullOrEmpty(args))
-                args = string.Format(", {0}", args);
-
-            PushMarshalKind(MarshalKind.GenericDelegate);
-
-            var returnTypePrinterResult = returnType.Visit(this);
-
-            PopMarshalKind();
-
-            return string.Format("Func<{0}{1}>", returnTypePrinterResult, args);
-        }
-
         private bool allowStrings = true;
 
         public override TypePrinterResult VisitPointerType(PointerType pointer,

src/Generator/Passes/CheckIgnoredDecls.cs

@@ -110,7 +110,7 @@ namespace CppSharp.Passes
             type.TryGetDeclaration(out decl);
             string msg = "internal";
             TypeMap typeMap;
-            if (!(type is FunctionType) && (decl == null ||
+            if ((decl == null ||
                 ((decl.GenerationKind != GenerationKind.Internal ||
                   Context.TypeMaps.FindTypeMap(type, out typeMap)) &&
                  !HasInvalidType(field, out msg))))

src/Generator/Passes/DelegatesPass.cs

@@ -76,6 +76,26 @@ namespace CppSharp.Passes
             return true;
         }
 
+        public override bool VisitProperty(Property property)
+        {
+            if (!base.VisitProperty(property))
+                return false;
+
+            property.QualifiedType = CheckForDelegate(property.QualifiedType, property);
+
+            return true;
+        }
+
+        public override bool VisitFieldDecl(Field field)
+        {
+            if (!base.VisitFieldDecl(field))
+                return false;
+
+            field.QualifiedType = CheckForDelegate(field.QualifiedType, field);
+
+            return true;
+        }
+
         private QualifiedType CheckForDelegate(QualifiedType type, ITypedDecl decl)
         {
             if (type.Type is TypedefType)

src/Generator/Passes/RenamePass.cs

@@ -190,8 +190,14 @@ namespace CppSharp.Passes
                 declarations.RemoveAll(d => specialization.TemplatedDecl.TemplatedDecl == d);
 
             var @class = decl.Namespace as Class;
-            if (@class != null && @class.IsDependent)
-                declarations.AddRange(@class.TemplateParameters);
+            if (@class != null)
+            {
+                declarations.AddRange(from typedefDecl in @class.Typedefs
+                                      where typedefDecl.Type.Desugar() is FunctionType
+                                      select typedefDecl);
+                if (@class.IsDependent)
+                    declarations.AddRange(@class.TemplateParameters);
+            }
 
             var result = declarations.Any(d => d != decl && d.Name == newName);
             if (result)

tests/CSharp/CSharp.Tests.cs

@@ -1261,6 +1261,16 @@ public unsafe class CSharpTests : GeneratorTestFixture
         Assert.That(CSharp.CSharp.TakeConstCharStarRef("Test"), Is.EqualTo("Test"));
     }
 
+    [Test]
+    public void Test()
+    {
+        using (var hasFunctionPtrField = new HasFunctionPtrField())
+        {
+            hasFunctionPtrField.FunctionPtrField = @string => @string.Length;
+            Assert.That(hasFunctionPtrField.FunctionPtrField("Test"), Is.EqualTo(4));
+        }
+    }
+
     public class Inter : SimpleInterface
     {
         public override int Size => s;

tests/CSharp/CSharp.cpp

@@ -1543,6 +1543,14 @@ void InterfaceTester::setInterface(SimpleInterface* i)
     interface = i;
 }
 
+HasFunctionPtrField::HasFunctionPtrField()
+{
+}
+
+HasFunctionPtrField::~HasFunctionPtrField()
+{
+}
+
 void va_listFunction(va_list v)
 {
 }

tests/CSharp/CSharp.h

@@ -1295,6 +1295,14 @@ private:
     SimpleInterface* interface;
 };
 
+class DLL_API HasFunctionPtrField
+{
+public:
+    HasFunctionPtrField();
+    ~HasFunctionPtrField();
+    int (*functionPtrField)(const char*);
+};
+
 DLL_API void va_listFunction(va_list v);
 DLL_API char* returnCharPointer();
 DLL_API const char* takeConstCharStarRef(const char*& c);