_ss_environment.php

<?php

// If we're requesting a different database for testing
if(isset($_REQUEST['db'])) {
	if(
		class_exists('PHPUnit_Runner_Version') // If the PHPUnit runner is loaded
		|| php_sapi_name() === "cli" // Or we're definitely in CLI mode
		|| (isset($_SERVER['REQUEST_URI']) && strpos($_SERVER['REQUEST_URI'], '/dev/tests') !== false) // Or we're running tests in-browser
	) {
		global $databaseConfig;

		switch ($_REQUEST['db']) {
			case 'sqlite':
			case 'sqlite3':
				define('SS_DATABASE_CLASS', 'SQLite3Database');
				define('SS_SQLITE_DATABASE_PATH', ':memory:');			
				$databaseConfig["path"] = ':memory:';
				break;
			default:
				user_error('Unknown database type: ' . $_REQUEST['db'], E_USER_WARNING);
		}
	}
}