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46 lines
942 B
Rust
46 lines
942 B
Rust
#![warn(clippy::readonly_write_lock)]
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use std::sync::RwLock;
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fn mutate_i32(x: &mut i32) {
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*x += 1;
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}
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fn accept_i32(_: i32) {}
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fn main() {
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let lock = RwLock::new(42);
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let lock2 = RwLock::new(1234);
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{
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let writer = lock.read().unwrap();
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//~^ ERROR: this write lock is used only for reading
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//~| NOTE: `-D clippy::readonly-write-lock` implied by `-D warnings`
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dbg!(&writer);
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}
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{
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let writer = lock.read().unwrap();
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//~^ ERROR: this write lock is used only for reading
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accept_i32(*writer);
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}
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{
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let mut writer = lock.write().unwrap();
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mutate_i32(&mut writer);
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dbg!(&writer);
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}
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{
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let mut writer = lock.write().unwrap();
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*writer += 1;
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}
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{
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let mut writer1 = lock.write().unwrap();
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let mut writer2 = lock2.write().unwrap();
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*writer2 += 1;
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*writer1 = *writer2;
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}
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}
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