Computing RexCall digest containing IN expressions leads to Exceptions

 /*  RexProgramTest */
  @Test public void testInDigest() {
    RexNode e = in(vInt(), literal(1), literal(2));
    assertThat(e.toString(), is("IN(?0.int0, 1, 2)"));
  }
 /*  RexProgramBuilder */
  protected RexNode in(Iterable<? extends RexNode> nodes) {
    return rexBuilder.makeCall(SqlStdOperatorTable.IN,
        ImmutableList.copyOf(nodes));
  }