Add diagnostic code for generic associated const error.

Author: quantheory

src/librustc_typeck/check/mod.rs

@@ -3773,9 +3773,9 @@ pub fn resolve_ty_and_def_ufcs<'a, 'b, 'tcx>(fcx: &FnCtxt<'b, 'tcx>,
         match def {
             def::DefAssociatedConst(..) => {
                 if ty::type_has_params(ty) || ty::type_has_self(ty) {
-                    fcx.sess().span_err(span,
-                                        "Associated consts cannot depend \
-                                         on type parameters or Self.");
+                    span_err!(fcx.sess(), span, E0329,
+                              "Associated consts cannot depend \
+                               on type parameters or Self.");
                     fcx.write_error(node_id);
                     return true;
                 }

src/librustc_typeck/diagnostics.rs

@@ -771,6 +771,7 @@ register_diagnostics! {
     E0326, // associated const implemented with different type from trait
     E0327, // referred to method instead of constant in match pattern
     E0328, // cannot implement Unsize explicitly
+    E0329, // associated const depends on type parameter or Self.
     E0366, // dropck forbid specialization to concrete type or region
     E0367, // dropck forbid specialization to predicate not in struct/enum
     E0369, // binary operation `<op>` cannot be applied to types

src/test/compile-fail/associated-const-type-parameters.rs

@@ -14,13 +14,13 @@ pub trait Foo {
     const MIN: i32;
 
     fn get_min() -> i32 {
-        Self::MIN //~ Associated consts cannot depend on type parameters or Self.
+        Self::MIN //~ ERROR E0329
     }
 }
 
 fn get_min<T: Foo>() -> i32 {
-    T::MIN; //~ Associated consts cannot depend on type parameters or Self.
-    <T as Foo>::MIN //~ Associated consts cannot depend on type parameters or Self.
+    T::MIN; //~ ERROR E0329
+    <T as Foo>::MIN //~ ERROR E0329
 }
 
 fn main() {}