Convert Eq impl to check Ord::Equal

Author: JulianKnodt

src/librustc_ast/ast.rs

@@ -310,7 +310,7 @@ pub type GenericBounds = Vec<GenericBound>;
 /// Specifies the enforced ordering for generic parameters. In the future,
 /// if we wanted to relax this order, we could override `PartialEq` and
 /// `PartialOrd`, to allow the kinds to be unordered.
-#[derive(PartialEq, Eq, Hash, Clone, Copy)]
+#[derive(Hash, Clone, Copy)]
 pub enum ParamKindOrd {
     Lifetime,
     Type,
@@ -340,6 +340,12 @@ impl PartialOrd for ParamKindOrd {
         Some(self.cmp(other))
     }
 }
+impl PartialEq for ParamKindOrd {
+    fn eq(&self, other: &Self) -> bool {
+        self.cmp(other) == Ordering::Equal
+    }
+}
+impl Eq for ParamKindOrd {}
 
 impl fmt::Display for ParamKindOrd {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

src/test/ui/const-generics/argument_order.stderr

@@ -11,7 +11,7 @@ LL |     let _: AlsoBad<7, 'static, u32, 'static, 17, u16>;
    |                       ^^^^^^^
    |
    = note: lifetime arguments must be provided before type arguments
-   = help: reorder the arguments: lifetimes, then consts, then types, then consts, then types: `<'a, 'b, N, T, M, U>`
+   = help: reorder the arguments: lifetimes, then consts: `<'a, 'b, N, T, M, U>`
 
 error: aborting due to 2 previous errors