Ticket #16953: 16953.no-single-file.2.diff

wp-includes/plugin.php

@@ -642 +642 @@
 function wp_register_plugin_realpath( $file ) {
         global $wp_plugin_paths;
 
+        // Normalize, but store as static to avoid constant recalculation of a
+        // constant value
+        static $wp_plugin_path, $wpmu_plugin_path;
+        if ( empty( $wp_plugin_path ) || empty( $wpmu_plugin_path ) ) {
+                $wp_plugin_path = wp_normalize_path( WP_PLUGIN_DIR );
+                $wpmu_plugin_path = wp_normalize_path( WPMU_PLUGIN_DIR );
+        }
+
         $plugin_path = wp_normalize_path( dirname( $file ) );
         $plugin_realpath = wp_normalize_path( dirname( realpath( $file ) ) );
 
+        if ( $plugin_path === $wp_plugin_path || $plugin_path === $wpmu_plugin_path ) {
+                return false;
+        }
+
         if ( $plugin_path !== $plugin_realpath ) {
                 $wp_plugin_paths[ $plugin_path ] = $plugin_realpath;
         }
+
+        return true;
 }
 
 /**

wp-settings.php

@@ -168 +168 @@
 
 // Load must-use plugins.
 foreach ( wp_get_mu_plugins() as $mu_plugin ) {
-        wp_register_plugin_realpath( $mu_plugin );
         include_once( $mu_plugin );
 }
 unset( $mu_plugin );