@Test
public void testSequence_withIterable() {

  Parser<?> parser =
      Parsers.sequence(Arrays.asList(Scanners.isChar('a'), Scanners.isChar('b')));
  assertEquals("sequence", parser.toString());
  assertEquals(null, parser.parse("ab", mode));
  assertFailure(mode, parser, "xb", 1, 1);
  assertFailure(mode, parser, "ax", 1, 2);
}