[gtk/builder-tool-fixes: 1/2] builder-tool: Handle GtkWidget::visible properly

[Matthias Clasen <matthiasc src gnome org>]

commit 40fe3d94ac2e502c2d5697d8dc7b3faedce5d93e
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat May 4 15:58:11 2019 +0000

    builder-tool: Handle GtkWidget::visible properly
    
    This property has a 'smart' default that depends
    on the class of the object we're creating. Take
    that into account when deciding whether to omit
    properties that are set to their default value.

 gtk/tools/gtk-builder-tool-simplify.c | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)
---
diff --git a/gtk/tools/gtk-builder-tool-simplify.c b/gtk/tools/gtk-builder-tool-simplify.c
index 4ef7373bd3..93c19e0a8c 100644
--- a/gtk/tools/gtk-builder-tool-simplify.c
+++ b/gtk/tools/gtk-builder-tool-simplify.c
@@ -358,8 +358,11 @@ get_property_pspec (MyParserData *data,
   return pspec;
 }
 
+static const char *get_class_name (Element *element);
+
 static gboolean
-value_is_default (MyParserData *data,
+value_is_default (Element      *element,
+                  MyParserData *data,
                   GParamSpec   *pspec,
                   const gchar  *value_string)
 {
@@ -377,7 +380,25 @@ value_is_default (MyParserData *data,
       ret = FALSE;
     }
   else
-    ret = g_param_value_defaults (pspec, &value);
+    {
+      /* GtkWidget::visible has a 'smart' default */
+      if (pspec->owner_type == GTK_TYPE_WIDGET &&
+          g_str_equal (pspec->name, "visible"))
+        {
+          const char *class_name = get_class_name (element);
+          GType type = g_type_from_name (class_name);
+          gboolean default_value;
+
+          if (g_type_is_a (type, GTK_TYPE_NATIVE))
+            default_value = FALSE;
+          else
+            default_value = TRUE;
+
+          ret = g_value_get_boolean (&value) == default_value;
+        }
+      else
+        ret = g_param_value_defaults (pspec, &value);
+    }
 
   g_value_reset (&value);
 
@@ -556,7 +577,7 @@ property_can_be_omitted (Element      *element,
   if (needs_explicit_setting (pspec, kind))
     return FALSE;
 
-  return value_is_default (data, pspec, value_string);
+  return value_is_default (element, data, pspec, value_string);
 }
 
 static gboolean