[gtk+] cssstylechange: Add helper function to print change

[Timm Bäder <baedert src gnome org>]

commit d3a0dfe81a67ec39e12652f022fc43c16b421a67
Author: Timm Bäder <mail baedert org>
Date:   Fri Feb 5 10:28:13 2016 +0100

    cssstylechange: Add helper function to print change
    
    So I don't have to print both styles to the console, paste them both
    into a file and then run diff on the 2 files anymore.

 gtk/gtkcssstylechange.c        |   44 ++++++++++++++++++++++++++++++++++++++++
 gtk/gtkcssstylechangeprivate.h |    2 +
 2 files changed, 46 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkcssstylechange.c b/gtk/gtkcssstylechange.c
index 0ce6120..400dfe8 100644
--- a/gtk/gtkcssstylechange.c
+++ b/gtk/gtkcssstylechange.c
@@ -110,3 +110,47 @@ gtk_css_style_change_changes_property (GtkCssStyleChange *change,
   return _gtk_bitmask_get (change->changes, id);
 }
 
+void
+gtk_css_style_change_print (GtkCssStyleChange *change,
+                            GString           *string)
+{
+  int i;
+  GtkCssStyle *old = gtk_css_style_change_get_old_style (change);
+  GtkCssStyle *new = gtk_css_style_change_get_new_style (change);
+
+  for (i = 0; i < GTK_CSS_PROPERTY_N_PROPERTIES; i ++)
+    {
+      if (gtk_css_style_change_changes_property (change, i))
+        {
+          GtkCssStyleProperty *prop;
+          GtkCssValue *value;
+          const char *name;
+
+          prop = _gtk_css_style_property_lookup_by_id (i);
+          name = _gtk_style_property_get_name (GTK_STYLE_PROPERTY (prop));
+
+          value = gtk_css_style_get_value (old, i);
+          _gtk_css_value_print (value, string);
+
+          g_string_append_printf (string, "%s: ", name);
+          _gtk_css_value_print (value, string);
+          g_string_append (string, "\n");
+
+          g_string_append_printf (string, "%s: ", name);
+          value = gtk_css_style_get_value (new, i);
+          _gtk_css_value_print (value, string);
+          g_string_append (string, "\n");
+        }
+    }
+
+}
+
+char *
+gtk_css_style_change_to_string (GtkCssStyleChange *change)
+{
+  GString *string = g_string_new ("");
+
+  gtk_css_style_change_print (change, string);
+
+  return g_string_free (string, FALSE);
+}
diff --git a/gtk/gtkcssstylechangeprivate.h b/gtk/gtkcssstylechangeprivate.h
index 078dee0..85b9a32 100644
--- a/gtk/gtkcssstylechangeprivate.h
+++ b/gtk/gtkcssstylechangeprivate.h
@@ -47,7 +47,9 @@ gboolean        gtk_css_style_change_affects            (GtkCssStyleChange
                                                          GtkCssAffects           affects);
 gboolean        gtk_css_style_change_changes_property   (GtkCssStyleChange      *change,
                                                          guint                   id);
+void            gtk_css_style_change_print              (GtkCssStyleChange      *change, GString *string);
 
+char *          gtk_css_style_change_to_string          (GtkCssStyleChange      *change);
 G_END_DECLS
 
 #endif /* __GTK_CSS_STYLE_CHANGE_PRIVATE_H__ */