Ticket #13780: 13780-check-theme-version-on-activate.diff

wp-includes/class-wp-theme.php

@@ -22 +22 @@
                 'Author'      => 'Author',
                 'AuthorURI'   => 'Author URI',
                 'Version'     => 'Version',
+                'Requires'    => 'Requires at least',
                 'Template'    => 'Template',
                 'Status'      => 'Status',
                 'Tags'        => 'Tags',

wp-includes/theme.php

@@ -661 +661 @@
  * @param string $stylesheet Stylesheet name
  */
 function switch_theme( $stylesheet ) {
-        global $wp_theme_directories, $sidebars_widgets;
-
-        if ( is_array( $sidebars_widgets ) )
-                set_theme_mod( 'sidebars_widgets', array( 'time' => time(), 'data' => $sidebars_widgets ) );
+        global $wp_theme_directories, $sidebars_widgets, $wp_version;
 
         $old_theme  = wp_get_theme();
         $new_theme = wp_get_theme( $stylesheet );
 
+        if ( version_compare( $wp_version, $new_theme->get('Requires'), '<' ) ) {
+                wp_die( sprintf( __('The theme %s requires WordPress %s or higher. Please <a href="%s">update WordPress</a>.'), '<strong>' . $new_theme->get('Name') . '</strong>', $new_theme->get('Requires'), network_admin_url('update-core.php') ) );
+        }
+
+        if ( is_array( $sidebars_widgets ) )
+                set_theme_mod( 'sidebars_widgets', array( 'time' => time(), 'data' => $sidebars_widgets ) );
+
         if ( func_num_args() > 1 ) {
                 $template = $stylesheet;
                 $stylesheet = func_get_arg( 1 );