clj-time: Parse datetime string with many formats, and original time zone intact

date.clj

(require '[clj-time.core :as t])
(require '[clj-time.format :as f])

(defn parse-date [s]
  (.. (f/formatter (t/default-time-zone)
                   "YYYY-MM-dd'T'HH:mm:ss.SSSZZ"
                   "YYYY-MM-dd'T'HH:mm:ssZZ"
                   "YYYY-MM-dd HH:mm:ss ZZ"
                   "EEE MMM dd YYYY HH:mm:ss zZ '('z')'")
      withOffsetParsed
      (parseDateTime s)))

date_test.clj

(defn- tz [year month day hour mins secs zone]
  (t/from-time-zone (t/date-time year month day hour mins secs)
                    (t/time-zone-for-offset zone)))

(defn- date-formats []
  (let [pst-time (tz 2015 2 13 14 52 32 -8)]
    {"2014-11-12 12:13:14 +0400" (tz 2014 11 12 12 13 14 4)
     "2014-11-12T12:13:14+0200"  (tz 2014 11 12 12 13 14 2)
     "2014-11-12T12:13:14.000Z"  (tz 2014 11 12 12 13 14 0)
     "2014-11-12T12:13:14Z"      (tz 2014 11 12 12 13 14 0)
     "Mon Feb 09 2015 14:52:32 GMT+0000 (GMT)" (tz 2015 2 9 14 52 32 0)
     "Fri Feb 13 2015 14:52:32 PST-0800 (PST)" pst-time}))

(deftest test-parse-date
  (doseq [[s t] (date-formats)]
    (is (= (parse-date s) t))))