rust/tests/ui/option_and_then_some.rs

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2019-08-15 03:53:11 +00:00
// run-rustfix
#![deny(clippy::option_and_then_some)]
// need a main anyway, use it get rid of unused warnings too
pub fn main() {
let x = Some(5);
// the easiest cases
let _ = x.and_then(Some);
let _ = x.and_then(|o| Some(o + 1));
// and an easy counter-example
let _ = x.and_then(|o| if o < 32 { Some(o) } else { None });
// Different type
let x: Result<u32, &str> = Ok(1);
let _ = x.and_then(Ok);
}
pub fn foo() -> Option<String> {
let x = Some(String::from("hello"));
Some("hello".to_owned()).and_then(|s| Some(format!("{}{}", s, x?)))
}
2019-08-19 05:41:47 +00:00
pub fn example2(x: bool) -> Option<&'static str> {
Some("a").and_then(|s| Some(if x { s } else { return None }))
}