Insert a version string into ClojureScript output

version.clj

(def ts (time/formatters :date-time-no-ms))

(defn git-hash []
  (let [p (.exec (Runtime/getRuntime) (into-array String ["/bin/sh" "-c"
                                                          "git rev-list --format=format:'%ct' --max-count=1 `git rev-parse HEAD`"]))]
    (.waitFor p)
    (let [s (-> (.getInputStream p)
                slurp
                string/trim)
          _ (prn s)
          [ch ts] (string/split s #"\n")
          ts (* 1000 (Long. ts)) ;; convert seconds to ms
          [_ ch] (re-matches #"commit (.+)" ch)]
      {:commit-hash ch
       :timestamp (tc/from-long ts)})))

(defmacro insert-version []
  (let [{:keys [commit-hash timestamp]} (git-hash)]
    (str (time/unparse ts timestamp) " | " commit-hash)))