CLJS-2340: Have js-keys delegate directly to good.object/getKeys

Author: mfikes

benchmark/cljs/benchmark_runner.cljs

@@ -31,6 +31,10 @@
 (println ";; amap")
 (simple-benchmark [arr (to-array (range 1000000))] (amap arr i ret (* 10 (aget arr i))) 1)
 
+(println ";; js-keys")
+(simple-benchmark [obj (js-obj "a" 1 "b" 2) f js-keys] (f obj) 400000)
+(simple-benchmark [obj (js-obj "a" 1 "b" 2 "c" 3 "d" 4 "e" 5 "f" 6) f js-keys] (f obj) 400000)
+
 (println ";;; instance?")
 ;; WARNING: will get compiled away under advanced
 (simple-benchmark [coll []] (instance? PersistentVector coll) 1000000)

src/main/cljs/cljs/core.cljs

@@ -2150,9 +2150,7 @@ reduces them without incurring seq initialization"
 (defn js-keys
   "Return the JavaScript keys for an object."
   [obj]
-  (let [keys (array)]
-    (gobject/forEach obj (fn [val key obj] (.push keys key)))
-    keys))
+  (gobject/getKeys obj))
 
 (defn js-delete
   "Delete a property from a JavaScript object."