csharp: Fix wrapping of private classes

Summary:
Sometimes, valid Eo objects of private classes can be returned from
methods. Currently we try to wrap in a minimal `Efl.Object` instance,
but as it is an abstract class, we can't instantiate directly.

This commits adds a dummy `Efl.ObjectRealized` to be instantiated when
wrapping such classes alongside a test case.

Fixes: T8258

Reviewers: felipealmeida, brunobelo, segfaultxavi, Jaehyun_Cho

Reviewed By: brunobelo

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D10101

src/bindings/mono/eo_mono/EoWrapper.cs

@@ -413,4 +413,15 @@ public abstract class EoWrapper : IWrapper, IDisposable
 
 } // namespace Eo
 
+/// <summary>Concrete realization of Efl.Object.
+///
+/// Some legacy classes (like Evas.Canvas) may be returned by some methods. As these classes are not bound, we
+/// allow minimal interaction with them through <see cref="Efl.Object" />.
+///
+/// But as <see cref="Efl.Object" /> is abstract, whis realized class will allow us to create C# instances of it.</summary>
+internal class ObjectRealized : Efl.Object
+{
+    protected ObjectRealized(Efl.Eo.Globals.WrappingHandle ch) : base(ch) { }
+}
+
 } // namespace Efl

src/bindings/mono/eo_mono/iwrapper.cs

@@ -843,7 +843,7 @@ public static class ClassRegister
 
             if (t == null)
             {
-                return typeof(Efl.Object);
+                return typeof(Efl.ObjectRealized);
             }
         }
 

src/tests/efl_mono/Eo.cs

@@ -621,4 +621,15 @@ class TestStaticInterfaceMembers
     }
 }
 
+class TestHiddenClasses
+{
+    public static void test_hidden_class()
+    {
+        var obj = new Dummy.TestObject();
+        var hidden = obj.HiddenObject;
+
+        Test.AssertEquals(hidden.Name, "hidden_object");
+    }
+}
+
 }

src/tests/efl_mono/dummy_hidden_object.c

@@ -0,0 +1,8 @@
+#include "libefl_mono_native_test.h"
+
+typedef struct Dummy_Hidden_Object_Data
+{
+} Dummy_Hidden_Object_Data;
+
+
+#include "dummy_hidden_object.eo.c"

src/tests/efl_mono/dummy_hidden_object.eo

@@ -0,0 +1,2 @@
+class Dummy.Hidden_Object extends Efl.Object {
+}

src/tests/efl_mono/dummy_test_object.c

@@ -22,6 +22,7 @@ typedef struct Dummy_Test_Object_Data
   Eo *iface_provider;
   int prop1;
   int prop2;
+  Eo *hidden_object;
 
   // Containers passed to C# as iterator/accessors
   Eina_Array *out_array;
@@ -75,6 +76,8 @@ _dummy_test_object_efl_object_constructor(Eo *obj, Dummy_Test_Object_Data *pd)
 {
    efl_constructor(efl_super(obj, DUMMY_TEST_OBJECT_CLASS));
    pd->provider = efl_add(DUMMY_NUMBERWRAPPER_CLASS, obj);
+   pd->hidden_object = efl_add(DUMMY_HIDDEN_OBJECT_CLASS, obj);
+   efl_name_set(pd->hidden_object, "hidden_object");
 
    if (efl_parent_get(obj) == NULL) { // Avoid recursion
        pd->iface_provider = efl_add(DUMMY_TEST_OBJECT_CLASS, obj);
@@ -4738,6 +4741,11 @@ int _dummy_test_object_dummy_test_iface_call_method_protected(const Eo *obj, EIN
     return dummy_test_iface_method_protected(obj, x);
 }
 
+Eo *_dummy_test_object_hidden_object_get(EINA_UNUSED const Eo *obj, Dummy_Test_Object_Data *pd)
+{
+    return pd->hidden_object;
+}
+
 // Inherit
 int _dummy_inherit_helper_receive_dummy_and_call_int_out(Dummy_Test_Object *x)
 {

src/tests/efl_mono/dummy_test_object.eo

@@ -1646,6 +1646,14 @@ class Dummy.Test_Object extends Efl.Object implements Dummy.Test_Iface {
          }
          return: const(ptr(Eina.Value_Type));
       }
+
+      @property hidden_object {
+         get {}
+
+         values {
+            obj: Efl.Object;
+         }
+      }
    }
    implements {
       Efl.Object.constructor;

src/tests/efl_mono/libefl_mono_native_test.h

@@ -56,6 +56,7 @@
 #include "dummy_part_holder.eo.h"
 #include "dummy_event_manager.eo.h"
 #include "dummy_constructible_object.eo.h"
+#include "dummy_hidden_object.eo.h"
 
 #include <interfaces/efl_part.eo.h>
 

src/tests/efl_mono/meson.build

@@ -10,9 +10,13 @@ eo_files = [
     'dummy_constructible_object.eo',
 ]
 
+private_eo_files = [
+    'dummy_hidden_object.eo'
+]
+
 eo_file_targets = []
 
-foreach eo_file : eo_files
+foreach eo_file : eo_files + private_eo_files
   eo_file_targets += custom_target('eolian_gen_' + eo_file,
     input : eo_file,
     output : [eo_file + '.h'],
@@ -35,6 +39,7 @@ efl_mono_native_test = library('efl_mono_native_test',
         'dummy_test_object.c',
         'dummy_event_manager.c',
         'dummy_constructible_object.c',
+        'dummy_hidden_object.c',
     ],
     dependencies : [ecore, eo, efl],
 )