[gtk/wip/matthiasc/css-change: 13/27] cssstyle: Try harder to skip initial values

[Matthias Clasen <matthiasc src gnome org>]

commit 791a81f092dfdc9f2da70305779f7728693d0b42
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jan 13 20:13:13 2020 -0500

    cssstyle: Try harder to skip initial values
    
    Compare values against the computed value of their
    properties initial value. This works for fine for
    all expect the border-width properties, whose special
    handling defeats this.

 gtk/gtkcssstyle.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)
---
diff --git a/gtk/gtkcssstyle.c b/gtk/gtkcssstyle.c
index 53561657cb..d6ff5cbb84 100644
--- a/gtk/gtkcssstyle.c
+++ b/gtk/gtkcssstyle.c
@@ -37,6 +37,7 @@
 #include "gtkstyleanimationprivate.h"
 #include "gtkstylepropertyprivate.h"
 #include "gtkstyleproviderprivate.h"
+#include "gtksettings.h"
 
 G_DEFINE_ABSTRACT_TYPE (GtkCssStyle, gtk_css_style, G_TYPE_OBJECT)
 
@@ -137,13 +138,24 @@ gtk_css_style_print (GtkCssStyle *style,
       GtkCssValue *value;
       const char *name;
 
-      section = gtk_css_style_get_section (style, i);
-      if (!section && skip_initial)
-        continue;
-
+      value = gtk_css_style_get_value (style, i);
       prop = _gtk_css_style_property_lookup_by_id (i);
+      if (skip_initial)
+        { 
+          GtkCssValue *initial = _gtk_css_style_property_get_initial_value (prop);
+          GtkCssStyle *default_style = gtk_css_static_style_get_default ();
+          GtkCssValue *computed = _gtk_css_value_compute (initial, i,
+                                                          GTK_STYLE_PROVIDER (gtk_settings_get_default ()),
+                                                          default_style,
+                                                          default_style);
+          gboolean is_initial = _gtk_css_value_equal (value, computed);
+          gtk_css_value_unref (computed);
+          if (is_initial)
+            continue;
+        }
+
+      section = gtk_css_style_get_section (style, i);
       name = _gtk_style_property_get_name (GTK_STYLE_PROPERTY (prop));
-      value = gtk_css_style_get_value (style, i);
 
       g_string_append_printf (string, "%*s%s: ", indent, "", name);
       _gtk_css_value_print (value, string);