Ticket #18501: 18501.patch

wp-includes/plugin.php

@@ -581 +581 @@
  * @return string the filesystem path of the directory that contains the plugin
  */
 function plugin_dir_path( $file ) {
-        return trailingslashit( dirname( $file ) );
+        $file          = str_replace(  '\\','/',   $file           ); // sanitize for Win32 installs
+        $file          = preg_replace( '|/+|','/', $file           ); // remove any duplicate slash
+        $plugin_dir    = str_replace(  '\\','/',   WP_PLUGIN_DIR   ); // sanitize for Win32 installs
+        $plugin_dir    = preg_replace( '|/+|','/', $plugin_dir     ); // remove any duplicate slash
+        $mu_plugin_dir = str_replace(  '\\','/',   WPMU_PLUGIN_DIR ); // sanitize for Win32 installs
+        $mu_plugin_dir = preg_replace( '|/+|','/', $mu_plugin_dir  ); // remove any duplicate slash
+
+        // Determine if plugin is in /plugins or /mu-plugins
+        if ( 0 === strpos( $file, $mu_plugin_dir ) )
+                $path = $mu_plugin_dir;
+        else
+                $path = $plugin_dir;
+
+        // Get relative path from plugins dir
+        $file = preg_replace( '#^' . preg_quote( $plugin_dir, '#' ) . '/|^' . preg_quote( $mu_plugin_dir, '#' ) . '/#', '', $file );
+        $file = trim( $file, '/' );
+
+        // Get the folder name and add it to the path
+        $folder = dirname( $file );
+        if ( '.' != $folder )
+                $path .= '/' . ltrim( $folder, '/' );
+
+        return trailingslashit( $path );
 }
 
 /**