static void ctxTestRule(S input, S ruleName) {
  ctxTestRule("", input, ruleName);
}

static void ctxTestRule(S prelude, S input, S ruleName) {
  //ruleName = addPrefix("Agent#", ruleName);
  S desc = prelude + input + " -> " + ruleName;
  print("\nTesting: " + desc);
  try {
    ctxContext().rulesFired.clear();
    ctxClearOutput();
    ctxProcessInput(input);
    ctxProcessRules();
    ctxDefaultOnEmptyOutput();
    S output = ctxGetOutput();
    bool ok1 = ctxContext().rulesFired.contains(ruleName);
    if (!ok1) desc += " was: " + struct(ctxContext().rulesFired);
    bool ok2 = nempty(output);
    if (!ok2)
      desc += " no output";
    else
      desc += " output: " + quote(output);
    addTestResult(desc, (boolToInt(ok1)+boolToInt(ok2))*50);
  } catch e {
    addTestResult(desc, e);
  }
}