Update util.js

Author: developit

src/util.js

@@ -2,6 +2,7 @@
 export const IS_NON_DIMENSIONAL = /acit|ex(?:s|g|n|p|$)|rph|grid|ows|mnc|ntw|ine[ch]|zoo|^ord|^--/i;
 
 export function encodeEntities(s) {
+	if (typeof s !== 'string') s = String(s);
 	let out = '';
 	for (let i=0; i<s.length; i++) {
 		let ch = s[i];