src/Report/ReporterFactory.php
public function registerReporter(ReporterInterface $reporter)
    {
        $format = $reporter->getFormat();

        if (isset($this->reporters[$format])) {
            throw new \UnexpectedValueException(sprintf('Reporter for format "%s" is already registered.', $format));
        }

        $this->reporters[$format] = $reporter;

        return $this;
    }
public function registerReporter(ReporterInterface $reporter)
    {
        $format = $reporter->getFormat();

        if (isset($this->reporters[$format])) {
            throw new \UnexpectedValueException(sprintf('Reporter for format "%s" is already registered.', $format));
        }

        $this->reporters[$format] = $reporter;

        return $this;
    }
@param ReporterInterface $reporter

@return $this