edje: Add property "part_exist"

This allows to safely verify if a part exists, without triggering any
potential call to NULL object, or even requiring the efl_part() handle
to be created.

This is perfectly equivalent to edje_object_part_exists(), but
implemented by both edje object and elm layout.

src/lib/edje/edje_legacy.c

@@ -1205,14 +1205,5 @@ edje_object_size_max_get(const Edje_Object *obj, int *maxw, int *maxh)
 EAPI Eina_Bool
 edje_object_part_exists(const Eo *obj, const char *part)
 {
-   Edje_Real_Part *rp;
-   Edje *ed;
-
-   if (!part) return EINA_FALSE;
-   ed = _edje_fetch(obj);
-   if (!ed) return EINA_FALSE;
-   rp = _edje_real_part_recursive_get(&ed, part);
-   if (!rp) return EINA_FALSE;
-
-   return EINA_TRUE;
+   return efl_layout_group_part_exist_get(obj, part);
 }

src/lib/edje/edje_util.c

@@ -3325,7 +3325,7 @@ _efl_canvas_layout_efl_layout_group_group_size_min_get(Eo *obj EINA_UNUSED, Edje
 }
 
 EOLIAN Eina_Size2D
-_efl_canvas_layout_efl_layout_group_group_size_max_get(Eo *obj EINA_UNUSED, Edje *ed EINA_UNUSED)
+_efl_canvas_layout_efl_layout_group_group_size_max_get(Eo *obj EINA_UNUSED, Edje *ed)
 {
    Eina_Size2D sz;
 
@@ -3343,6 +3343,19 @@ _efl_canvas_layout_efl_layout_group_group_size_max_get(Eo *obj EINA_UNUSED, Edje
    return sz;
 }
 
+EOLIAN Eina_Bool
+_efl_canvas_layout_efl_layout_group_part_exist_get(Eo *obj EINA_UNUSED, Edje *ed, const char *part)
+{
+   Edje_Real_Part *rp;
+
+   if (!part) return EINA_FALSE;
+   if (ed->delete_me) return EINA_FALSE;
+   rp = _edje_real_part_recursive_get(&ed, part);
+   if (!rp) return EINA_FALSE;
+
+   return EINA_TRUE;
+}
+
 EOLIAN void
 _efl_canvas_layout_efl_layout_calc_calc_force(Eo *obj EINA_UNUSED, Edje *ed)
 {

src/lib/edje/efl_canvas_layout.eo

@@ -116,6 +116,7 @@ class Efl.Canvas.Layout (Efl.Canvas.Group, Efl.File, Efl.Container, Efl.Part,
       Efl.Layout.Group.group_size_min { get; }
       Efl.Layout.Group.group_size_max { get; }
       Efl.Layout.Group.group_data { get; }
+      Efl.Layout.Group.part_exist { get; }
       Efl.Layout.Signal.message_send;
       Efl.Layout.Signal.signal_callback_add;
       Efl.Layout.Signal.signal_callback_del;

src/lib/edje/efl_layout_group.eo

@@ -98,6 +98,28 @@ interface Efl.Layout.Group
             val: string; [[The data's value string.]]
          }
       }
+      @property part_exist {
+         [[Whether the given part exists in this group.
+
+           This is mostly equivalent to verifying the part type on the object
+           as would be done in C as follows:
+             (efl_canvas_layout_part_type_get(efl_part(obj, "partname")) !=
+                EFL_CANVAS_LAYOUT_PART_TYPE_NONE)
+
+           The differences are that will silently return $false if the part
+           does not exist, and this will return $true if the part is of type
+           $SPACER in the EDC file ($SPACER parts have type $NONE).
+
+           See also @Efl.Canvas.Layout.Part.part_type.
+         ]]
+         get { [[Returns $true if the part exists in the EDC group.]] }
+         keys {
+            part: string @nonull; [[The part name to check.]]
+         }
+         values {
+            exists: bool; [[$true if the part exists, $false otherwise.]]
+         }
+      }
    }
 }
 

src/lib/elementary/efl_ui_layout.c

@@ -1575,6 +1575,14 @@ _efl_ui_layout_efl_layout_group_group_size_max_get(Eo *obj, Efl_Ui_Layout_Data *
    return efl_layout_group_size_max_get(wd->resize_obj);
 }
 
+EOLIAN static Eina_Bool
+_efl_ui_layout_efl_layout_group_part_exist_get(Eo *obj, Efl_Ui_Layout_Data *_pd EINA_UNUSED, const char *part)
+{
+   ELM_WIDGET_DATA_GET_OR_RETURN(obj, wd, EINA_FALSE);
+
+   return efl_layout_group_part_exist_get(wd->resize_obj, part);
+}
+
 /* layout's sizing evaluation is deferred. evaluation requests are
  * queued up and only flag the object as 'changed'. when it comes to
  * Evas's rendering phase, it will be addressed, finally (see

src/lib/elementary/efl_ui_layout.eo

@@ -59,6 +59,7 @@ class Efl.Ui.Layout (Efl.Ui.Widget, Efl.Part, Efl.Container, Efl.File,
       Efl.Layout.Group.group_data { get; }
       Efl.Layout.Group.group_size_min { get; }
       Efl.Layout.Group.group_size_max { get; }
+      Efl.Layout.Group.part_exist { get; }
       Efl.Ui.Widget.widget_sub_object_add;
       Efl.Ui.Widget.theme_apply;
       Efl.Ui.Widget.on_disabled_update;