Kahlan\Plugin\Double::_generateSignature PHP Method

    protected static function _generateSignature($method)
    {
        $params = [];
        $isVariadic = Suite::$PHP >= 7 ? $method->isVariadic() : false;
        foreach ($method->getParameters() as $num => $parameter) {
            $typehint = Inspector::typehint($parameter);
            $name = $parameter->getName();
            $name = $name && $name !== '...' ? $name : 'param' . $num;
            $reference = $parameter->isPassedByReference() ? '&' : '';
            $default = '';
            if ($parameter->isDefaultValueAvailable()) {
                $default = var_export($parameter->getDefaultValue(), true);
                $default = ' = ' . preg_replace('/\\s+/', '', $default);
            } elseif ($parameter->isOptional()) {
                if ($isVariadic && $parameter->isVariadic()) {
                    $reference = '...';
                    $default = '';
                } else {
                    $default = ' = NULL';
                }
            }
            $typehint = $typehint ? $typehint . ' ' : $typehint;
            $params[] = "{$typehint}{$reference}\${$name}{$default}";
        }
        return join(', ', $params);
    }