Optimize arrayUnique (#6871)

diff --git a/src/scales/scale.time.js b/src/scales/scale.time.js
index e2f74e056651c2d8b1c9e81bfd5982c7f1a99ac3..92b6a200612df411672deec34f6970b34b4dfd8a 100644 (file)
--- a/src/scales/scale.time.js
+++ b/src/scales/scale.time.js
@@ -66,19 +66,18 @@ function sorter(a, b) {
 }
 
 function arrayUnique(items) {
-       const hash = {};
-       const out = [];
-       let i, ilen, item;
+       const set = new Set();
+       let i, ilen;
 
        for (i = 0, ilen = items.length; i < ilen; ++i) {
-               item = items[i];
-               if (!hash[item]) {
-                       hash[item] = true;
-                       out.push(item);
-               }
+               set.add(items[i]);
+       }
+
+       if (set.size === ilen) {
+               return items;
        }
 
-       return out;
+       return [...set];
 }
 
 /**