public static function getPluginFile( $slug ) {

		// Load plugin.php if not already included by core.
		if ( ! function_exists( 'get_plugins' ) ) {
			require ABSPATH . '/wp-admin/includes/plugin.php';
		}

		$plugins = get_plugins();

		foreach ( $plugins as $file => $info ) {

			// Get the basename of the plugin.
			$basename = dirname( plugin_basename( $file ) );
			if ( $basename === $slug ) {
				return $file;
			}
		}

		return null;
	}