[gtk/matthiasc/css-change-tracking-4: 9/11] Change the superset matcher implementation

[Matthias Clasen <matthiasc src gnome org>]

commit e5db8a0ce9e33084314e231eb88c5681b4b99a28
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Jan 16 23:14:10 2020 -0500

    Change the superset matcher implementation
    
    Matchers are stack-allocated, so including a pointer
    to the subset in the superset matcher is risky, at best.
    Change it to copy the subset matcher. For now, this does
    not change anything in the matchers functionality, but
    we will take advantage of it in the following commits.

 gtk/gtkcssmatcher.c        | 23 ++++++++++++++++++-----
 gtk/gtkcssmatcherprivate.h |  5 ++++-
 2 files changed, 22 insertions(+), 6 deletions(-)
---
diff --git a/gtk/gtkcssmatcher.c b/gtk/gtkcssmatcher.c
index 34f0df54ca..a7f973450f 100644
--- a/gtk/gtkcssmatcher.c
+++ b/gtk/gtkcssmatcher.c
@@ -530,7 +530,7 @@ gtk_css_matcher_superset_has_name (const GtkCssMatcher     *matcher,
                                    /*interned*/ const char *name,
                                    gboolean                 match)
 {
-  return _gtk_css_matcher_has_name (matcher->superset.subset, name, match);
+  return _gtk_css_matcher_has_name ((GtkCssMatcher *)&matcher->superset.subset, name, match);
 }
 
 static gboolean
@@ -538,7 +538,7 @@ gtk_css_matcher_superset_has_class (const GtkCssMatcher *matcher,
                                     GQuark               class_name,
                                     gboolean             match)
 {
-  return _gtk_css_matcher_has_class (matcher->superset.subset, class_name, match);
+  return _gtk_css_matcher_has_class ((GtkCssMatcher *)&matcher->superset.subset, class_name, match);
 }
 
 static gboolean
@@ -546,7 +546,7 @@ gtk_css_matcher_superset_has_id (const GtkCssMatcher *matcher,
                                  const char          *id,
                                  gboolean             match)
 {
-  return _gtk_css_matcher_has_id (matcher->superset.subset, id, match);
+  return _gtk_css_matcher_has_id ((GtkCssMatcher *)&matcher->superset.subset, id, match);
 }
 
 static gboolean
@@ -564,7 +564,7 @@ gtk_css_matcher_superset_print (const GtkCssMatcher *matcher,
                                 GString             *string)
 {
   g_string_append (string, "SUPERSET(");
-  gtk_css_matcher_print (matcher->superset.subset, string);
+  gtk_css_matcher_print ((GtkCssMatcher *)&matcher->superset.subset, string);
   g_string_append (string, ")");
 }
 
@@ -587,5 +587,18 @@ _gtk_css_matcher_superset_init (GtkCssMatcher       *matcher,
   g_return_if_fail (subset != NULL);
 
   matcher->superset.klass = &GTK_CSS_MATCHER_SUPERSET;
-  matcher->superset.subset = subset;
+  switch (subset->klass->type)
+    {
+    case GTK_CSS_MATCHER_TYPE_WIDGET_PATH:
+      matcher->superset.subset.path = subset->path;
+      break;
+    case GTK_CSS_MATCHER_TYPE_NODE:
+      matcher->superset.subset.node = subset->node;
+      break;
+    case GTK_CSS_MATCHER_TYPE_ANY:
+    case GTK_CSS_MATCHER_TYPE_SUPERSET:
+    default:
+      g_assert_not_reached ();
+      break;
+    }
 }
diff --git a/gtk/gtkcssmatcherprivate.h b/gtk/gtkcssmatcherprivate.h
index 505900e582..ea345ac053 100644
--- a/gtk/gtkcssmatcherprivate.h
+++ b/gtk/gtkcssmatcherprivate.h
@@ -84,7 +84,10 @@ struct _GtkCssMatcherNode {
 
 struct _GtkCssMatcherSuperset {
   const GtkCssMatcherClass *klass;
-  const GtkCssMatcher      *subset;
+  union {
+    GtkCssMatcherWidgetPath   path;
+    GtkCssMatcherNode         node;
+  } subset;
 };
 
 union _GtkCssMatcher {