Add test

Author: Randl

library/core/src/clone.rs

@@ -258,10 +258,8 @@ pub macro Clone($item:item) {
 /// Use closures allow captured values to be automatically used.
 /// This is similar to have a closure that you would call `.use` over each captured value.
 #[unstable(feature = "ergonomic_clones", issue = "132290")]
-#[rustc_const_unstable(feature = "const_clone", issue = "142757")]
-#[const_trait]
 #[lang = "use_cloned"]
-pub trait UseCloned: ~const Clone {
+pub trait UseCloned: Clone {
     // Empty.
 }
 
@@ -270,7 +268,7 @@ macro_rules! impl_use_cloned {
         $(
             #[unstable(feature = "ergonomic_clones", issue = "132290")]
             #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
-            impl const UseCloned for $t {}
+            impl UseCloned for $t {}
         )*
     }
 }
@@ -565,7 +563,8 @@ mod impls {
     }
 
     #[unstable(feature = "never_type", issue = "35121")]
-    impl Clone for ! {
+    #[rustc_const_unstable(feature = "const_clone", issue = "142757")]
+    impl const Clone for ! {
         #[inline]
         fn clone(&self) -> Self {
             *self

tests/ui/traits/const-traits/const-traits-core.rs

@@ -1,6 +1,6 @@
-//@ run-pass
 #![feature(
-    const_trait_impl, const_default, ptr_alignment_type, ascii_char, f16, f128, sync_unsafe_cell,
+    const_trait_impl, const_default, const_clone, ptr_alignment_type,
+    ascii_char, f16, f128, sync_unsafe_cell,
 )]
 #![allow(dead_code)]
 // core::default
@@ -43,4 +43,27 @@ const REF_CELL: std::cell::RefCell<()> = Default::default();
 const UNSAFE_CELL: std::cell::UnsafeCell<()> = Default::default();
 const SYNC_UNSAFE_CELL: std::cell::SyncUnsafeCell<()> = Default::default();
 
+// core::clone
+const UNIT_CLONE: () = UNIT.clone();
+//~^ ERROR: the trait bound `(): const Clone` is not satisfied
+const BOOL_CLONE: bool = BOOL.clone();
+const CHAR_CLONE: char = CHAR.clone();
+const ASCII_CHAR_CLONE: std::ascii::Char = ASCII_CHAR.clone();
+//~^ ERROR: the trait bound `Char: const Clone` is not satisfied
+const USIZE_CLONE: usize = USIZE.clone();
+const U8_CLONE: u8 = U8.clone();
+const U16_CLONE: u16 = U16.clone();
+const U32_CLONE: u32 = U32.clone();
+const U64_CLONE: u64 = U64.clone();
+const U128_CLONE: u128 = U128.clone();
+const I8_CLONE: i8 = I8.clone();
+const I16_CLONE: i16 = I16.clone();
+const I32_CLONE: i32 = I32.clone();
+const I64_CLONE: i64 = I64.clone();
+const I128_CLONE: i128 = I128.clone();
+const F16_CLONE: f16 = F16.clone();
+const F32_CLONE: f32 = F32.clone();
+const F64_CLONE: f64 = F64.clone();
+const F128_CLONE: f128 = F128.clone();
+
 fn main() {}

tests/ui/traits/const-traits/const-traits-core.stderr

@@ -0,0 +1,15 @@
+error[E0277]: the trait bound `(): const Clone` is not satisfied
+  --> $DIR/const-traits-core.rs:47:29
+   |
+LL | const UNIT_CLONE: () = UNIT.clone();
+   |                             ^^^^^
+
+error[E0277]: the trait bound `Char: const Clone` is not satisfied
+  --> $DIR/const-traits-core.rs:51:55
+   |
+LL | const ASCII_CHAR_CLONE: std::ascii::Char = ASCII_CHAR.clone();
+   |                                                       ^^^^^
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.