From bc4fa6b198557a7f3989eb0865e2c77ac7451d29 Mon Sep 17 00:00:00 2001
From: kibigo! <marrus-sh@users.noreply.github.com>
Date: Sun, 3 Dec 2017 23:26:40 -0800
Subject: Rename themes -> flavours ? ?

---
 .../flavours/glitch/util/load_polyfills.js         | 39 ++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 app/javascript/flavours/glitch/util/load_polyfills.js

(limited to 'app/javascript/flavours/glitch/util/load_polyfills.js')

diff --git a/app/javascript/flavours/glitch/util/load_polyfills.js b/app/javascript/flavours/glitch/util/load_polyfills.js
new file mode 100644
index 000000000..8927b7358
--- /dev/null
+++ b/app/javascript/flavours/glitch/util/load_polyfills.js
@@ -0,0 +1,39 @@
+// Convenience function to load polyfills and return a promise when it's done.
+// If there are no polyfills, then this is just Promise.resolve() which means
+// it will execute in the same tick of the event loop (i.e. near-instant).
+
+function importBasePolyfills() {
+  return import(/* webpackChunkName: "base_polyfills" */ './base_polyfills');
+}
+
+function importExtraPolyfills() {
+  return import(/* webpackChunkName: "extra_polyfills" */ './extra_polyfills');
+}
+
+function loadPolyfills() {
+  const needsBasePolyfills = !(
+    window.Intl &&
+    Object.assign &&
+    Number.isNaN &&
+    window.Symbol &&
+    Array.prototype.includes
+  );
+
+  // Latest version of Firefox and Safari do not have IntersectionObserver.
+  // Edge does not have requestIdleCallback and object-fit CSS property.
+  // This avoids shipping them all the polyfills.
+  const needsExtraPolyfills = !(
+    window.IntersectionObserver &&
+    window.IntersectionObserverEntry &&
+    'isIntersecting' in IntersectionObserverEntry.prototype &&
+    window.requestIdleCallback &&
+    'object-fit' in (new Image()).style
+  );
+
+  return Promise.all([
+    needsBasePolyfills && importBasePolyfills(),
+    needsExtraPolyfills && importExtraPolyfills(),
+  ]);
+}
+
+export default loadPolyfills;
-- 
cgit