Ticket #8446: 8446-valid-classnames-for-post-categories-and-tags.patch

wp-includes/formatting.php

@@ -76 +76 @@
 }
 
 /**
+ * clean invalid chars from css class names
+ * 
+ * invalid chars will be replaced with '_', if the class
+ * should not be treated as a suffix for an existing class,
+ * then invalid classes will be prefixed with 'a_' to 
+ * become valid again. 
+ * 
+ * @since 2.7.2
+ * 
+ * @param  array|string $class  array or string with class(es)
+ * @param  bool         $suffix optional wether or not class(es) 
+ *                                                              are treated as being a suffix 
+ *                                                              (defaults to true)
+ * @return string       classname(es) cleaned  
+ */
+function clean_css_classnames($class, $suffix = true)
+{
+        if (is_array($class)) {
+                $return = array();
+                foreach($class as $single)
+                        $return[] = clean_css_classnames($single, $suffix);
+                return $return; 
+        }       
+        
+        $class = preg_replace('|[^_a-z0-9-]|i', '_', $class);
+        
+        if (false == $suffix && 0 == preg_match('|^-?[_a-z]+[_a-z0-9-]*$|i', $class))
+                $class = 'a_' . $class;
+                        
+        return $class;
+}
+
+/**
  * Accepts matches array from preg_replace_callback in wpautop() or a string.
  *
  * Ensures that the contents of a <<pre>>...<</pre>> HTML block are not

wp-includes/post-template.php

@@ -320 +320 @@
                 if ( empty($cat->slug ) )
                         continue;
                 $classes[] = 'category-' . $cat->slug;
+                $classes[] = 'categoryid-' . $cat->term_id;
         }
 
         // Tags
         foreach ( (array) get_the_tags($post->ID) as $tag ) {
                 if ( empty($tag->slug ) )
                         continue;
-                $classes[] = 'tag-' . $tag->slug;
+                $classes[] = 'tag-' . $tag->slug;               
+                $classes[] = 'tagid-' . $tag->term_id;
         }
 
         if ( !empty($class) ) {
@@ -334 +336 @@
                         $class = preg_split('#\s+#', $class);
                 $classes = array_merge($classes, $class);
         }
+        
+        $classes = clean_css_classnames($classes, false);
 
         return apply_filters('post_class', $classes, $class, $post_id);
 }