Nested separated_list for empty input fails?

[zbraniecki]

• Rust version : 1.39
• nom version : 5.0.1

Test case

fn and_parser(i: &str) -> IResult<&str, Vec<&str>> {
    separated_list(tag(" and "), tag("foo"))(i)
}

fn or_parser(i: &str) -> IResult<&str, Vec<Vec<&str>>> {
    separated_list(tag(" or "), and_parser)(i)
}

assert_eq!(parser("foo and foo or foo"), Ok(("", vec![vec!["foo", "foo"], vec!["foo"]])));

// FAILS with `Err(Error(("", SeparatedList)))`
assert_eq!(or_parser(""), Ok(("", vec![vec![]])));

Why wouldn't that work?

[zbraniecki]

According to @pcpthm analysis in https://users.rust-lang.org/t/nom-5-and-nested-separated-list/34590/2?u=zbraniecki it seems like a bug in nom

[Geal]

now that ##1170 is merged, this should be more consistent