src/tools/clippy/tests/ui/derive.rs

   1
   2
   3 #![feature(untagged_unions)]
   4
   5 #![allow(dead_code)]
   6 #![warn(expl_impl_clone_on_copy)]
   7
   8 use std::hash::{Hash, Hasher};
   9
  10 #[derive(PartialEq, Hash)]
  11 struct Foo;
  12
  13 impl PartialEq<u64> for Foo {
  14     fn eq(&self, _: &u64) -> bool { true }
  15 }
  16
  17 #[derive(Hash)]
  18 struct Bar;
  19
  20 impl PartialEq for Bar {
  21     fn eq(&self, _: &Bar) -> bool { true }
  22 }
  23
  24 #[derive(Hash)]
  25 struct Baz;
  26
  27 impl PartialEq<Baz> for Baz {
  28     fn eq(&self, _: &Baz) -> bool { true }
  29 }
  30
  31 #[derive(PartialEq)]
  32 struct Bah;
  33
  34 impl Hash for Bah {
  35     fn hash<H: Hasher>(&self, _: &mut H) {}
  36 }
  37
  38 #[derive(Copy)]
  39 struct Qux;
  40
  41 impl Clone for Qux {
  42     fn clone(&self) -> Self { Qux }
  43 }
  44
  45 // looks like unions don't support deriving Clone for now
  46 #[derive(Copy)]
  47 union Union {
  48     a: u8,
  49 }
  50
  51 impl Clone for Union {
  52     fn clone(&self) -> Self {
  53         Union {
  54             a: 42,
  55         }
  56     }
  57 }
  58
  59 // See #666
  60 #[derive(Copy)]
  61 struct Lt<'a> {
  62     a: &'a u8,
  63 }
  64
  65 impl<'a> Clone for Lt<'a> {
  66     fn clone(&self) -> Self { unimplemented!() }
  67 }
  68
  69 // Ok, `Clone` cannot be derived because of the big array
  70 #[derive(Copy)]
  71 struct BigArray {
  72     a: [u8; 65],
  73 }
  74
  75 impl Clone for BigArray {
  76     fn clone(&self) -> Self { unimplemented!() }
  77 }
  78
  79 // Ok, function pointers are not always Clone
  80 #[derive(Copy)]
  81 struct FnPtr {
  82     a: fn() -> !,
  83 }
  84
  85 impl Clone for FnPtr {
  86     fn clone(&self) -> Self { unimplemented!() }
  87 }
  88
  89 // Ok, generics
  90 #[derive(Copy)]
  91 struct Generic<T> {
  92     a: T,
  93 }
  94
  95 impl<T> Clone for Generic<T> {
  96     fn clone(&self) -> Self { unimplemented!() }
  97 }
  98
  99 fn main() {}