rust-clippy/tests/ui/result_map_unit_fn_unfixable.rs
2019-09-25 14:45:18 -07:00

40 lines
1.1 KiB
Rust

#![feature(never_type)]
#![warn(clippy::result_map_unit_fn)]
#![allow(unused)]
fn do_nothing<T>(_: T) {}
fn diverge<T>(_: T) -> ! {
panic!()
}
fn plus_one(value: usize) -> usize {
value + 1
}
#[rustfmt::skip]
fn result_map_unit_fn() {
x.field.map(|value| { do_nothing(value); do_nothing(value) });
x.field.map(|value| if value > 0 { do_nothing(value); do_nothing(value) });
// Suggestion for the let block should be `{ ... }` as it's too difficult to build a
// proper suggestion for these cases
x.field.map(|value| {
do_nothing(value);
do_nothing(value)
});
x.field.map(|value| { do_nothing(value); do_nothing(value); });
// The following should suggest `if let Ok(_X) ...` as it's difficult to generate a proper let variable name for them
let res: Result<!, usize> = Ok(42).map(diverge);
"12".parse::<i32>().map(diverge);
let res: Result<(), usize> = Ok(plus_one(1)).map(do_nothing);
// Should suggest `if let Ok(_y) ...` to not override the existing foo variable
let y: Result<usize, usize> = Ok(42);
y.map(do_nothing);
}
fn main() {}