static ErrorCounter gazelle_performMultipleTests(S data, O... _) {
  new ErrorCounter errorCounter;
  SS tests = equalsSignsSections(data);
  S performOnly = stringPar performOnly(_);
  for (S name, test : tests) {
    if (performOnly != null && !eqic(trim(tok_dropStuffInRoundBrackets(name)), trim(performOnly))) continue;
    printAsciiHeading(upper(name));
    gazelle_fakery_performTest(test, paramsPlus(_, +errorCounter));
  }
  ret errorCounter;
}