Ticket #17689: 17689-noformatting.diff

src/wp-includes/taxonomy.php

@@ -2091 +2091 @@
         $name = wp_unslash($name);
         $description = wp_unslash($description);
 
-        if ( empty($slug) )
-                $slug = sanitize_title($name);
+        if ( empty( $slug ) ) {
+                $name = trim( $name );
+                $sanitized_name = sanitize_title( $name );
+                $exists = $wpdb->get_row( $wpdb->prepare( "SELECT term_id, slug FROM $wpdb->terms WHERE name = %s ORDER BY term_id ASC LIMIT 1", $name ) );
+                if ( ! empty( $exists ) && term_exists( $exists->term_id, $taxonomy ) ) {
+                        if ( $sanitized_name === $exists->slug )
+                                return new WP_Error( 'term_exists', __( 'A term with the name provided already exists.' ) );
 
+                        $slug = $exists->slug;
+                } elseif ( ! empty( $exists ) ) {
+                        $exists = $wpdb->get_var( $wpdb->prepare( "SELECT term_id FROM $wpdb->terms WHERE slug = %s ORDER BY term_id ASC LIMIT 1", $sanitized_name ) );
+                        if ( ! empty( $exists ) )
+                                return new WP_Error( 'term_exists', __( 'A term with the name provided already exists.' ) );
+                } else {
+                        $slug = $sanitized_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) );