#![warn(clippy::drop_copy, clippy::forget_copy)] #![allow(clippy::toplevel_ref_arg, clippy::drop_ref, clippy::forget_ref, unused_mut)] use std::mem::{drop, forget}; use std::vec::Vec; #[derive(Copy, Clone)] struct SomeStruct; struct AnotherStruct { x: u8, y: u8, z: Vec, } impl Clone for AnotherStruct { fn clone(&self) -> AnotherStruct { AnotherStruct { x: self.x, y: self.y, z: self.z.clone(), } } } fn main() { let s1 = SomeStruct {}; let s2 = s1; let s3 = &s1; let mut s4 = s1; let ref s5 = s1; drop(s1); drop(s2); drop(s3); drop(s4); drop(s5); forget(s1); forget(s2); forget(s3); forget(s4); forget(s5); let a1 = AnotherStruct { x: 255, y: 0, z: vec![1, 2, 3], }; let a2 = &a1; let mut a3 = a1.clone(); let ref a4 = a1; let a5 = a1.clone(); drop(a2); drop(a3); drop(a4); drop(a5); forget(a2); let a3 = &a1; forget(a3); forget(a4); let a5 = a1.clone(); forget(a5); } #[allow(unused)] #[allow(clippy::unit_cmp)] fn issue9482(x: u8) { fn println_and(t: T) -> T { println!("foo"); t } match x { 0 => drop(println_and(12)), // Don't lint (copy type), we only care about side-effects 1 => drop(println_and(String::new())), // Don't lint (no copy type), we only care about side-effects 2 => { drop(println_and(13)); // Lint, even if we only care about the side-effect, it's already in a block }, 3 if drop(println_and(14)) == () => (), // Lint, idiomatic use is only in body of `Arm` 4 => drop(2), // Lint, not a fn/method call _ => (), } }