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mod and_then;
mod common;
mod map_err;
mod trait_;
mod try_filter_map;
mod try_flat_map;

pub use and_then::*;
pub use map_err::*;
pub use trait_::*;
pub use try_filter_map::*;
pub use try_flat_map::*;

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn try_flat_map_test_1() {
        let input = vec![
            Ok(vec![Ok(1usize), Ok(2)]),
            Ok(vec![Err("err"), Ok(3)]),
            Ok(vec![Ok(4)]),
        ];
        let output: Vec<_> = input.into_iter().try_flat_map(Ok).collect();
        assert_eq!(output, vec![Ok(1usize), Ok(2), Err("err")]);
    }

    #[test]
    fn try_flat_map_test_2() {
        let input = vec![Ok(vec![Ok(1usize), Ok(2)]), Err("err"), Ok(vec![Ok(3)])];
        let output: Vec<_> = input.into_iter().try_flat_map(Ok).collect();
        assert_eq!(output, vec![Ok(1usize), Ok(2), Err("err")]);
    }

    #[test]
    fn try_filter_map_test() {
        let input = vec![
            Ok(Some(1usize)),
            Ok(None),
            Ok(Some(3usize)),
            Err("err"),
            Ok(Some(4usize)),
        ];
        let output: Vec<_> = input.into_iter().try_filter_map(Ok).collect();
        assert_eq!(output, vec![Ok(1usize), Ok(3), Err("err")]);
    }

    #[test]
    fn and_then_test() {
        let input = vec![Ok(1isize), Ok(2), Err("err"), Ok(3)];
        let output: Vec<_> = input.into_iter().and_then(|val| Ok(-val)).collect();
        assert_eq!(output, vec![Ok(-1), Ok(-2), Err("err")]);
    }
}