@Test
public void test_null_and_missing() {

  FunctionExpression and = dsl.and(DSL.ref(BOOL_TYPE_MISSING_VALUE_FIELD, BOOLEAN),
      DSL.ref(BOOL_TYPE_MISSING_VALUE_FIELD, BOOLEAN));
  assertEquals(BOOLEAN, and.type());
  assertEquals(LITERAL_MISSING, and.valueOf(valueEnv()));
  and = dsl.and(DSL.ref(BOOL_TYPE_NULL_VALUE_FIELD, BOOLEAN),
      DSL.ref(BOOL_TYPE_NULL_VALUE_FIELD, BOOLEAN));
  assertEquals(BOOLEAN, and.type());
  assertEquals(LITERAL_NULL, and.valueOf(valueEnv()));
  and = dsl.and(DSL.ref(BOOL_TYPE_NULL_VALUE_FIELD, BOOLEAN),
      DSL.ref(BOOL_TYPE_MISSING_VALUE_FIELD, BOOLEAN));
  assertEquals(BOOLEAN, and.type());
  assertEquals(LITERAL_MISSING, and.valueOf(valueEnv()));
  and = dsl.and(DSL.ref(BOOL_TYPE_MISSING_VALUE_FIELD, BOOLEAN),
      DSL.ref(BOOL_TYPE_NULL_VALUE_FIELD, BOOLEAN));
  assertEquals(BOOLEAN, and.type());
  assertEquals(LITERAL_MISSING, and.valueOf(valueEnv()));
}