parse-test.cljs

(ns insta.parse-test
  (:require [cljs.test :refer-macros [is]]
            [devcards.core :refer-macros [deftest]]
            [instaparse.core :as insta :refer-macros [defparser]]))

(insta/defparser parser
                 (str "<S>                   = template\n\n<FWS>                 = #'[ \\t\\r\\n]*'\n\n"
                      ""
                      "when                  = <'~='> #'[a-zA-Z0-9\\-]+'\n"
                      "when-not              = <'~!'> #'[a-zA-Z0-9\\-]+'\n"
                      "repeated              = <'~*'>\n\n"
                      ""
                      "text                  = #'[^~]*'\n"
                      "variable              = <'~$'> #'[a-zA-Z0-9\\-]+'\n\n"
                      ""
                      "metadata              = (when | when-not | repeated | <FWS>)* <FWS> <\":\">\n"
                      "script                = (variable | text)*\n\n"
                      ""
                      "<template>            = [metadata] <FWS> script"))

(deftest parse-test
  (is (= [[:metadata [:repeated] [:when-not "new-customer"] [:when "old-customer"] [:when "high-value"]]
          [:script
           [:text "Your product "]
           [:variable "product"]
           [:text " will be shipped to you on "]
           [:variable "date-year"]
           [:text ", thanks! Cost is $"]
           [:variable "au-cost"]
           [:text "."]]]
         (insta/parse parser "~* ~!new-customer ~=old-customer ~=high-value: Your product ~$product will be shipped to you on ~$date-year, thanks! Cost is $~$au-cost."))))

(defn parse-template
  [text]
  (let [result (insta/parse parser text)]
    (if-not (insta/failure? result)
      (let [parsed (into {} (map (juxt first rest) result))]
        (assoc parsed :variables (filter #(= :variable (first %))
                                         (:script parsed)))))))