1 #![warn(clippy::result_map_unit_fn)]
2 #![feature(never_type)]
6 field: Result<usize, usize>,
9 fn do_nothing<T>(_: T) {}
11 fn diverge<T>(_: T) -> ! {
15 fn plus_one(value: usize) -> usize {
20 fn result_map_unit_fn() {
21 let x = HasResult { field: Ok(10) };
23 x.field.map(|value| { do_nothing(value); do_nothing(value) });
25 x.field.map(|value| if value > 0 { do_nothing(value); do_nothing(value) });
27 // Suggestion for the let block should be `{ ... }` as it's too difficult to build a
28 // proper suggestion for these cases
33 x.field.map(|value| { do_nothing(value); do_nothing(value); });
35 // The following should suggest `if let Ok(_X) ...` as it's difficult to generate a proper let variable name for them
36 let res: Result<!, usize> = Ok(42).map(diverge);
37 "12".parse::<i32>().map(diverge);
39 let res: Result<(), usize> = Ok(plus_one(1)).map(do_nothing);
41 // Should suggest `if let Ok(_y) ...` to not override the existing foo variable
42 let y: Result<usize, usize> = Ok(42);