// run-rustfix
#![allow(dead_code)]
#![warn(clippy::manual_filter_map)]
#![allow(clippy::redundant_closure)] // FIXME suggestion may have redundant closure

fn main() {
    // is_some(), unwrap()
    let _ = (0..).filter_map(|a| to_opt(a));

    // ref pattern, expect()
    let _ = (0..).filter_map(|a| to_opt(a));

    // is_ok(), unwrap_or()
    let _ = (0..).filter_map(|a| to_res(a).ok());
}

fn no_lint() {
    // no shared code
    let _ = (0..).filter(|n| *n > 1).map(|n| n + 1);

    // very close but different since filter() provides a reference
    let _ = (0..).filter(|n| to_opt(n).is_some()).map(|a| to_opt(a).unwrap());

    // similar but different
    let _ = (0..).filter(|n| to_opt(n).is_some()).map(|n| to_res(n).unwrap());
    let _ = (0..)
        .filter(|n| to_opt(n).map(|n| n + 1).is_some())
        .map(|a| to_opt(a).unwrap());
}

fn to_opt<T>(_: T) -> Option<T> {
    unimplemented!()
}

fn to_res<T>(_: T) -> Result<T, ()> {
    unimplemented!()
}