rust/tests/ui/if_then_some_else_none.rs
2021-03-07 02:08:46 +09:00

67 lines
1.5 KiB
Rust

#![warn(clippy::if_then_some_else_none)]
fn main() {
// Should issue an error.
let _ = if foo() {
println!("true!");
Some("foo")
} else {
None
};
// Should not issue an error since the `else` block has a statement besides `None`.
let _ = if foo() {
println!("true!");
Some("foo")
} else {
eprintln!("false...");
None
};
// Should not issue an error since there are more than 2 blocks in the if-else chain.
let _ = if foo() {
println!("foo true!");
Some("foo")
} else if bar() {
println!("bar true!");
Some("bar")
} else {
None
};
let _ = if foo() {
println!("foo true!");
Some("foo")
} else {
bar().then(|| {
println!("bar true!");
"bar"
})
};
// Should not issue an error since the `then` block has `None`, not `Some`.
let _ = if foo() { None } else { Some("foo is false") };
// Should not issue an error since the `else` block doesn't use `None` directly.
let _ = if foo() { Some("foo is true") } else { into_none() };
// Should not issue an error since the `then` block doesn't use `Some` directly.
let _ = if foo() { into_some("foo") } else { None };
}
fn foo() -> bool {
unimplemented!()
}
fn bar() -> bool {
unimplemented!()
}
fn into_some<T>(v: T) -> Option<T> {
Some(v)
}
fn into_none<T>() -> Option<T> {
None
}