rust-clippy/tests/ui/let_underscore_lock.rs

#![warn(clippy::let_underscore_lock)]

extern crate parking_lot;

fn main() {
    use parking_lot::lock_api::RawMutex;
    use parking_lot::{Mutex, RwLock};

    let p_m: Mutex<()> = Mutex::const_new(RawMutex::INIT, ());
    let _ = p_m.lock();
    //~^ ERROR: non-binding `let` on a synchronization lock

    let p_m1 = Mutex::new(0);
    let _ = p_m1.lock();
    //~^ ERROR: non-binding `let` on a synchronization lock

    let p_rw = RwLock::new(0);
    let _ = p_rw.read();
    //~^ ERROR: non-binding `let` on a synchronization lock
    let _ = p_rw.write();
    //~^ ERROR: non-binding `let` on a synchronization lock

    // These shouldn't throw an error.
    let _ = p_m;
    let _ = p_m1;
    let _ = p_rw;
}

fn uplifted() {
    // shouldn't lint std locks as they were uplifted as rustc's `let_underscore_lock`

    let m = std::sync::Mutex::new(());
    let rw = std::sync::RwLock::new(());

    let _ = m.lock();
    let _ = rw.read();
    let _ = rw.write();
    let _ = m.try_lock();
    let _ = rw.try_read();
    let _ = rw.try_write();

    let _ = m;
    let _ = rw;
}