add @has

Author: BoxyUwU

src/test/rustdoc/const-generics/const-evaluatable-checked.rs

@@ -2,4 +2,6 @@
 #![feature(const_evaluatable_checked, const_generics)]
 #![allow(incomplete_features)]
 // make sure that `ConstEvaluatable` predicates dont cause rustdoc to ICE #77647
+// @has foo/struct.Ice.html '//pre[@class="rust struct"]' \
+//      'pub struct Ice<const N: usize> where [(); N + 1]: ;'
 pub struct Ice<const N: usize> where [(); N + 1]:;