docs: private static Expression normalizeInPredicateToEquality(Expression expression)
      {
          if (expression instanceof InPredicate) {
              InPredicate inPredicate = (InPredicate) expression;
              if (inPredicate.getValueList() instanceof InListExpression) {
                  InListExpression valueList = (InListExpression) inPredicate.getValueList();
                  if (valueList.getValues().size() == 1) {
                      return new ComparisonExpression(ComparisonExpression.Operator.EQUAL, inPredicate.getValue(), Iterables.getOnlyElement(valueList.getValues()));
                  }
              }
          }
          return expression;
      }