@Test
    public void testToString() {
        Seq<Integer> oneTwoThree = Seq.of(1, 2, 3);

        // [#118] toString() operations on a Stream are buffered
        assertEquals("123", oneTwoThree.toString());
        assertEquals("123", oneTwoThree.toString());

        assertEquals("1, 2, 3", oneTwoThree.toString(", "));
        assertEquals("1, 2, 3", oneTwoThree.toString(", "));

        assertEquals("1, null, 3", Seq.of(1, null, 3).toString(", "));
    }
@author Lukas Eder
@author Roman Tkalenko
jOOL/src/test/java/org/jooq/lambda/SeqTest.java