Don't include DelayedAlias in illegal cycle checks

crates/compiler/solve/tests/solve_expr.rs

@@ -7324,4 +7324,21 @@ mod solve_expr {
             "OList",
         );
     }
+
+    #[test]
+    fn rosetree_with_result_is_legal_recursive_type() {
+        infer_eq_without_problem(
+            indoc!(
+                r#"
+                Rose a : [Rose (Result (List (Rose a)) I64)]
+
+                x : Rose I64
+                x = Rose (Ok [])
+
+                x
+                "#
+            ),
+            "Rose I64",
+        );
+    }
 }

crates/compiler/types/src/types.rs

@@ -1482,6 +1482,8 @@ impl Type {
             Type::Apply(Symbol::LIST_LIST | Symbol::SET_SET, _, _) => false,
             Type::Apply(..) => internal_error!("cannot chase an Apply!"),
             Type::Alias { .. } => internal_error!("should be dealiased"),
+            // Must be conservative here because we don't know what the alias expands to yet
+            Type::DelayedAlias(..) => false,
             // Non-composite types are trivially narrow
             _ => true,
         }