Remove code duplication by unifying the certificatelist. You should now check for isInstallCert to determine wether this certificate should be installed or removed. Leaving the getInstallCertificates and getRemoveCertificates in place for compatibilty would have been easier to keep the tests stable.

#ifndef COMMONTEST_H
#define COMMONTEST_H

#include <QObject>

class CommonTest: public QObject
{
  Q_OBJECT

private Q_SLOTS:
  void testStrBase64Decode();
  void testInvalidInput();
};
#endif