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// run-rustfix
#![warn(clippy::significant_drop_tightening)]
use std::sync::Mutex;
pub fn complex_return_triggers_the_lint() -> i32 {
fn foo() -> i32 {
1
}
let mutex = Mutex::new(1);
let lock = mutex.lock().unwrap();
let _ = *lock;
let _ = *lock;
drop(lock);
foo()
}
pub fn path_return_can_be_ignored() -> i32 {
let mutex = Mutex::new(1);
let lock = mutex.lock().unwrap();
let rslt = *lock;
let _ = *lock;
rslt
}
pub fn post_bindings_can_be_ignored() {
let mutex = Mutex::new(1);
let lock = mutex.lock().unwrap();
let rslt = *lock;
let another = rslt;
let _ = another;
}
pub fn unnecessary_contention_with_multiple_owned_results() {
{
let mutex = Mutex::new(1i32);
let lock = mutex.lock().unwrap();
let _ = lock.abs();
let _ = lock.is_positive();
}
{
let mutex = Mutex::new(1i32);
let lock = mutex.lock().unwrap();
let rslt0 = lock.abs();
let rslt1 = lock.is_positive();
drop(lock);
do_heavy_computation_that_takes_time((rslt0, rslt1));
}
}
pub fn unnecessary_contention_with_single_owned_results() {
{
let mutex = Mutex::new(1i32);
let lock = mutex.lock().unwrap();
let _ = lock.abs();
}
{
let mutex = Mutex::new(vec![1i32]);
let mut lock = mutex.lock().unwrap();
lock.clear();
}
{
let mutex = Mutex::new(1i32);
let rslt0 = mutex.lock().unwrap().abs();
do_heavy_computation_that_takes_time(rslt0);
}
{
let mutex = Mutex::new(vec![1i32]);
mutex.lock().unwrap().clear();
do_heavy_computation_that_takes_time(());
}
}
// Marker used for illustration purposes.
pub fn do_heavy_computation_that_takes_time<T>(_: T) {}
fn main() {}
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