src/Query/FiltersAbstract.php
public function appendValueFilter($key, $value)
    {
        if (!empty($value)) {
            if ($this->getValues($key)) {
                return $this->append($key, $value);
            } else {
                return $this->addValuesFilter($key, [$value]);
            }
        } else {
            //do nothing
            return $this;
        }
    }
public function appendValueFilter($key, $value)
    {
        if (!empty($value)) {
            if ($this->getValues($key)) {
                return $this->append($key, $value);
            } else {
                return $this->addValuesFilter($key, [$value]);
            }
        } else {
            //do nothing
            return $this;
        }
    }
Adiciona um valor a ValuesFilter existente.

@param string $key
@param type   $value

@return bool