tup.appendField(map);
DataAtom output = new DataAtom();
EvalFunc<DataAtom> count = new COUNT();
FilterFunc isEmpty = new IsEmpty();
assertTrue(isEmpty.exec(tup));
count.exec(tup,output);
assertTrue(output.numval() == 0);
map.put("a", new DataAtom("a"));
assertFalse(isEmpty.exec(tup));
count.exec(tup,output);
assertTrue(output.numval() == 1);
map.put("b", new Tuple());
assertFalse(isEmpty.exec(tup));
count.exec(tup,output);
assertTrue(output.numval() == 2);
}