tests/ui/lint/let_underscore/let_underscore_lock.rs

//@ check-fail
use std::sync::{Arc, Mutex};

struct Struct<T> {
    a: T,
}

fn main() {
    let data = Arc::new(Mutex::new(0));
    let _ = data.lock().unwrap(); //~ERROR non-binding let on a synchronization lock

    let _ = data.lock(); //~ERROR non-binding let on a synchronization lock

    let (_, _) = (data.lock(), 1); //~ERROR non-binding let on a synchronization lock

    let (_a, Struct { a: _ }) = (0, Struct { a: data.lock() }); //~ERROR non-binding let on a synchronization lock

    (_ , _) = (data.lock(), 1); //~ERROR non-binding let on a synchronization lock

    let _b;
    (_b, Struct { a: _ }) = (0, Struct { a: data.lock() }); //~ERROR non-binding let on a synchronization lock
}