Annotation specializes ability

compiler/can/src/def.rs

@@ -1218,7 +1218,9 @@ fn canonicalize_pending_value_def<'a>(
                 }
             };
 
-            if let Pattern::Identifier(symbol) = loc_can_pattern.value {
+            if let Pattern::Identifier(symbol)
+            | Pattern::AbilityMemberSpecialization { ident: symbol, .. } = loc_can_pattern.value
+            {
                 let def = single_can_def(
                     loc_can_pattern,
                     loc_can_expr,

compiler/solve/tests/solve_expr.rs

@@ -5860,4 +5860,23 @@ mod solve_expr {
             [("hash", "Id")],
         )
     }
+
+    #[test]
+    fn ability_checked_specialization_with_annotation_only() {
+        check_inferred_abilities(
+            indoc!(
+                r#"
+                app "test" provides [ hash ] to "./platform"
+
+                Hash has
+                    hash : a -> U64 | a has Hash
+
+                Id := U64
+
+                hash : Id -> U64
+                "#
+            ),
+            [("hash", "Id")],
+        )
+    }
 }