From e15aeda2210db31f93d03c0827b2ceeaee973b35 Mon Sep 17 00:00:00 2001
From: Quincy Morgan <2046746+quincylvania@users.noreply.github.com>
Date: Tue, 13 Oct 2020 16:02:26 -0400
Subject: [PATCH] Switch to core-js for polyfills

---
 babel.config.json              |  2 ++
 config/rollup.config.legacy.js |  4 +++-
 modules/id.js                  | 11 ++++++-----
 package.json                   |  5 ++---
 4 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/babel.config.json b/babel.config.json
index 52fedc958..3be60f4ab 100644
--- a/babel.config.json
+++ b/babel.config.json
@@ -2,6 +2,8 @@
   "presets": [
     [
       "@babel/preset-env", {
+        "useBuiltIns": "usage",
+        "corejs": 3,
         "modules": false
       }
     ]
diff --git a/config/rollup.config.legacy.js b/config/rollup.config.legacy.js
index 92c39fe78..8e9ad0df1 100644
--- a/config/rollup.config.legacy.js
+++ b/config/rollup.config.legacy.js
@@ -29,7 +29,9 @@ export default {
     commonjs(),
     json({ indent: '' }),
     babel({
-      babelHelpers: 'bundled'
+      babelHelpers: 'bundled',
+      // avoid circular dependencies due to `useBuiltIns: usage` option
+      exclude: [/\/core-js\//]
     })
   ]
 };
diff --git a/modules/id.js b/modules/id.js
index f53265dfe..b34557a48 100644
--- a/modules/id.js
+++ b/modules/id.js
@@ -1,10 +1,12 @@
-import 'browser-polyfills';
-import 'es6-symbol/implement';
+// polyfills newer JS functionality for older browsers
+import 'core-js/stable';
 import 'regenerator-runtime/runtime';
-import 'string.fromcodepoint/auto';
+
+// polyfill window.fetch and AbortController (not included in core-js)
+import 'whatwg-fetch';
 import 'abortcontroller-polyfill/dist/polyfill-patch-fetch';
 
-// polyfill requestIdleCallback
+// polyfill idle callback functions (not included in core-js)
 window.requestIdleCallback = window.requestIdleCallback ||
     function(cb) {
         var start = Date.now();
@@ -17,7 +19,6 @@ window.requestIdleCallback = window.requestIdleCallback ||
             });
         });
     };
-
 window.cancelIdleCallback = window.cancelIdleCallback ||
     function(id) {
         window.cancelAnimationFrame(id);
diff --git a/package.json b/package.json
index c4d286305..3fc6337f4 100644
--- a/package.json
+++ b/package.json
@@ -50,9 +50,8 @@
     "abortcontroller-polyfill": "^1.4.0",
     "aes-js": "^3.1.2",
     "alif-toolkit": "^1.2.9",
-    "browser-polyfills": "~1.5.0",
+    "core-js": "^3.6.5",
     "diacritics": "1.3.0",
-    "es6-symbol": "^3.1.3",
     "fast-deep-equal": "~3.1.1",
     "fast-json-stable-stringify": "2.1.0",
     "lodash-es": "~4.17.15",
@@ -63,7 +62,7 @@
     "pannellum": "2.5.6",
     "rbush": "3.0.1",
     "regenerator-runtime": "^0.13.7",
-    "string.fromcodepoint": "1.0.0",
+    "whatwg-fetch": "^3.4.1",
     "which-polygon": "2.2.0"
   },
   "devDependencies": {