### Question:
ModelToVLogConverter { static String[][] toVLogFactTuples(final Collection<Fact> facts) { final String[][] tuples = new String[facts.size()][]; int i = 0; for (final Fact fact : facts) { final String[] vLogFactTuple = ModelToVLogConverter.toVLogFactTuple(fact); tuples[i] = vLogFactTuple; i++; } return tuples; } private  ModelToVLogConverter();  static final String PREDICATE_ARITY_SUFFIX_SEPARATOR; }### Answer:
@Test public void testToVLogFactTuples() { final Constant c1 = Expressions.makeAbstractConstant("1"); final Constant c2 = Expressions.makeAbstractConstant("2"); final Constant c3 = Expressions.makeAbstractConstant("3"); final Fact atom1 = Expressions.makeFact("p1", Arrays.asList(c1)); final Fact atom2 = Expressions.makeFact("p2", Arrays.asList(c2, c3)); final String[][] vLogTuples = ModelToVLogConverter.toVLogFactTuples(Arrays.asList(atom1, atom2)); final String[][] expectedTuples = { { "1" }, { "2", "3" } }; assertArrayEquals(expectedTuples, vLogTuples); }