From 0e9548f415528c21d161e3c47f778300e3629f0e Mon Sep 17 00:00:00 2001
From: Guillaume Chau <alphadelta.fg@gmail.com>
Date: Sat, 23 Mar 2019 20:11:38 +0100
Subject: [PATCH] fix: detect polyfilled Map & Set objects, closes #744

---
 src/util.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/util.js b/src/util.js
index fe16fae5a0..9f33ac5f86 100644
--- a/src/util.js
+++ b/src/util.js
@@ -131,9 +131,9 @@ function replacer (key) {
   } else if (type === 'symbol') {
     return `[native Symbol ${Symbol.prototype.toString.call(val)}]`
   } else if (val !== null && type === 'object') {
-    if (val instanceof Map) {
+    if (val instanceof Map || val.toString() === '[object Map]') {
       return encodeCache.cache(val, () => getCustomMapDetails(val))
-    } else if (val instanceof Set) {
+    } else if (val instanceof Set || val.toString() === '[object Set]') {
       return encodeCache.cache(val, () => getCustomSetDetails(val))
     } else if (val instanceof RegExp) {
       // special handling of native type