rust-clippy/tests/ui/redundant_closure_call_fixable.rs
Quinn Sinclair e0228eeb94 Fixes FP in redundant_closure_call when closures are passed to macros
There are cases where the closure call is needed in some macros, this in
particular occurs when the closure has parameters. To handle this case,
we allow the lint when there are no parameters in the closure, or the
closure is outside a macro invocation.

fixes: #11274, #1553
changelog: FP: [`redundant_closure_call`] when closures with parameters
are passed in macros.
2024-01-13 17:45:30 +01:00

113 lines
2.2 KiB
Rust

#![feature(async_closure)]
#![warn(clippy::redundant_closure_call)]
#![allow(clippy::redundant_async_block)]
#![allow(clippy::type_complexity)]
#![allow(unused)]
async fn something() -> u32 {
21
}
async fn something_else() -> u32 {
2
}
fn main() {
let a = (|| 42)();
let b = (async || {
let x = something().await;
let y = something_else().await;
x * y
})();
let c = (|| {
let x = 21;
let y = 2;
x * y
})();
let d = (async || something().await)();
macro_rules! m {
() => {
(|| 0)()
};
}
macro_rules! m2 {
() => {
(|| m!())()
};
}
m2!();
issue9956();
}
fn issue9956() {
assert_eq!((|| || 43)()(), 42);
// ... and some more interesting cases I've found while implementing the fix
// not actually immediately calling the closure:
let a = (|| 42);
dbg!(a());
// immediately calling it inside of a macro
dbg!((|| 42)());
// immediately calling only one closure, so we can't remove the other ones
let a = (|| || || 123)();
dbg!(a()());
// nested async closures
let a = (|| || || || async || 1)()()()()();
let h = async { a.await };
// macro expansion tests
macro_rules! echo {
($e:expr) => {
$e
};
}
let a = (|| echo!(|| echo!(|| 1)))()()();
assert_eq!(a, 1);
let a = (|| echo!((|| 123)))()();
assert_eq!(a, 123);
// chaining calls, but not closures
fn x() -> fn() -> fn() -> fn() -> i32 {
|| || || 42
}
let _ = x()()()();
fn bar() -> fn(i32, i32) {
foo
}
fn foo(_: i32, _: i32) {}
bar()((|| || 42)()(), 5);
foo((|| || 42)()(), 5);
}
async fn issue11357() {
(|| async {})().await;
}
mod issue11707 {
use core::future::Future;
fn spawn_on(fut: impl Future<Output = ()>) {}
fn demo() {
spawn_on((|| async move {})());
}
}
fn avoid_double_parens() {
std::convert::identity((|| 13_i32 + 36_i32)()).leading_zeros();
}
fn fp_11274() {
macro_rules! m {
($closure:expr) => {
$closure(1)
};
}
m!(|x| println!("{x}"));
}