Inconsistent behavior with a simple spec that uses a regex op in an instrumented function

clojure-spec-regex-instrument-confusion.clj

(s/def ::test (s/cat :k keyword? :rest (s/* pos-int?)))

(s/conform ::test [:foo 1 2 3 4])
;; => {:k :foo, :rest [1 2 3 4]}

(s/conform (s/spec ::test) [:foo 1 2 3 4])
;; => {:k :foo, :rest [1 2 3 4]}

(s/conform (s/cat :t ::test) [:foo 1 2 3 4])
;; => {:t {:k :foo, :rest [1 2 3 4]}}

(s/conform (s/cat :t (s/spec ::test)) [:foo 1 2 3 4])
;; => :clojure.spec.alpha/invalid

(defn test-fn [test] nil)
(s/fdef test-fn :args (s/cat :t ::test) :ret nil?)

(stest/instrument `test-fn)
(test-fn [:foo 1 2 3 4])
;; => exception

(s/fdef test-fn :args (s/cat :t (s/spec ::test)) :ret nil?)

(stest/instrument `test-fn)
(test-fn [:foo 1 2 3 4])
;; => nil

;; Note that in order to get test-fn to pass instrumentation,
;; its :args must use the same form which conform considers invalid