add cljs test helpers file

test/com/rpl/specter/cljs_test_helpers.clj

@@ -0,0 +1,16 @@
+(ns com.rpl.specter.cljs-test-helpers
+  (:require [clojure.test.check             
+             [generators :as gen]
+             [properties :as prop]]))
+
+;; it seems like gen/bind and gen/return are a monad (hence the names)
+(defmacro for-all+ [bindings & body]
+  (let [parts (partition 2 bindings)
+        vars (vec (map first parts))
+        genned (reduce
+                (fn [curr [v code]]
+                  `(cljs.test.check.generators/bind ~code (fn [~v] ~curr)))
+                `(cljs.test.check.generators/return ~vars)
+                (reverse parts))]
+    `(cljs.test.check.properties/for-all [~vars ~genned]
+                   ~@body )))