Ticket #17689: non-alnum-terms.diff

wp-includes/taxonomy.php

@@ -2052 +2052 @@
         $name = stripslashes($name);
         $description = stripslashes($description);
 
-        if ( empty($slug) )
-                $slug = sanitize_title($name);
+        if ( empty( $slug ) ) {
+                $name = trim( $name );
+                
+                // check for a term like "$$$" so it isn't repeatedly added
+                if ( preg_match_all( '#[^:alnum:]#', $name, $matches ) && count( $matches[0] ) === strlen( $name ) ) {
+                        $exists = $wpdb->get_row( $wpdb->prepare( "SELECT term_id, slug FROM $wpdb->terms WHERE name = %s", $name ) );
+                        if ( ! empty( $exists ) ) {
+                                if ( term_exists( $exists->term_id, $taxonomy ) )
+                                        return new WP_Error( 'term_exists', __( 'A term with the name provided already exists.' ) );
+                                
+                                // use the existing slug or the term will never match in term_exists
+                                $slug = $exists->slug;
+                        }
 
+                } else {
+                        $slug = sanitize_title( $name );
+                }
+        }
+
         $term_group = 0;
         if ( $alias_of ) {
                 $alias = $wpdb->get_row( $wpdb->prepare( "SELECT term_id, term_group FROM $wpdb->terms WHERE slug = %s", $alias_of) );