src/Builder/AttachmentBuilder.php
private function setParameter($name, $value)
    {
        if (null !== $value && empty($value)) {
            return $this;
        }

        $this->data[$name] = $value;

        return $this;
    }
private function setParameter($name, $value)
    {
        if (null !== $value && empty($value)) {
            return $this;
        }

        $this->data[$name] = $value;

        return $this;
    }
Sets values on non-empty parameters.
Set $value to null to remove the custom value.

@param string $name
@param $value

@return $this