[#479] Add babashka.version system property

src/babashka/main.clj

@@ -444,14 +444,17 @@ If neither -e, -f, or --socket-repl are specified, then the first argument that
   (binding [*unrestricted* true]
     (sci/binding [reflection-var false
                   core/data-readers @core/data-readers]
-      (let [{:keys [:version :shell-in :edn-in :shell-out :edn-out
+      (let [{version-opt :version
+             :keys [:shell-in :edn-in :shell-out :edn-out
                     :help? :file :command-line-args
                     :expressions :stream?
                     :repl :socket-repl :nrepl
                     :verbose? :classpath
                     :main :uberscript :describe?] :as _opts}
             (parse-opts args)
-            _ (when main (System/setProperty "babashka.main" main))
+            _ (do ;; set properties
+                (when main (System/setProperty "babashka.main" main))
+                (System/setProperty "babashka.version" version))
             read-next (fn [*in*]
                         (if (pipe-signal-received?)
                           ::EOF
@@ -532,7 +535,7 @@ If neither -e, -f, or --socket-repl are specified, then the first argument that
             exit-code
             (or exit-code
                 (second
-                 (cond version
+                 (cond version-opt
                        [(print-version) 0]
                        help?
                        [(print-help) 0]

test-resources/babashka/version.clj

@@ -0,0 +1,13 @@
+(require '[clojure.string :as str])
+
+(def babashka-version (System/getProperty "babashka.version"))
+;; e.g. 0.1.3-SNAPSHOT
+
+(defn compare-version [v]
+  (nat-int? (compare
+             (mapv #(Integer. %)
+                   (take 3 (str/split babashka-version  #"[\.\-]"))) v)))
+
+(prn (compare-version [0 1 2])) ;; true
+(prn (compare-version [0 1 3])) ;; true
+(prn (compare-version [0 1 4])) ;; false

test/babashka/main_test.clj

@@ -485,6 +485,10 @@
 (deftest data-diff-test
   (is (= [[nil 1] [nil 2] [1 nil 2]] (bb nil "(require '[clojure.data :as d]) (d/diff [1 1 2] [1 2 2])"))))
 
+(deftest version-test
+  (is (= "true\ntrue\nfalse\n"
+         (test-utils/bb nil (.getPath (io/file "test-resources" "babashka" "version.clj"))))))
+
 ;;;; Scratch
 
 (comment