validate element visibility utility params

jlmakes · jlmakes · commit ece4bbf9409a · 2018-06-16T16:25:37.000-07:00
Logically, I think I've got a grip on the issue, but not well enough to recreate it today. Fixes jlmakes#440 (?)
diff --git a/src/utils/is-element-visible.js b/src/utils/is-element-visible.js
@@ -1,5 +1,7 @@
-export default function isElementVisible(element) {
+export default function isElementVisible(element = {}) {
 	const container = this.store.containers[element.containerId]
+	if (!container) return
+
 	const viewFactor = Math.max(0, Math.min(1, element.config.viewFactor))
 	const viewOffset = element.config.viewOffset
 
