From 9c024757b6de5b408afe7204e0c2d1fc9800b15f Mon Sep 17 00:00:00 2001
From: JC Brand <jc@opkode.com>
Date: Tue, 13 Aug 2019 19:30:20 +0200
Subject: [PATCH] Bugfix: `TypeError: o.getAttribute is not a function
 converse-chatview.js`

can cause messages to not appear.

* Check against null not Element.
* Avoid iterating over non-Element nodes
---
 CHANGES.md        |  1 +
 src/utils/html.js | 18 +++++++++---------
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index 747193622..5974fa81d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -6,6 +6,7 @@
 - Reconnect if the server doesn't respond to a `ping` within 10 seconds.
 - Don't query for MAM MUC messages before the cached messages have been restored (another cause of duplicate messages).
 - Show an error message and option to retry when fetching of the MAM archive times out
+- Bugfix: `TypeError: o.getAttribute is not a function converse-chatview.js` (can cause messages to not appear).
 
 ## 5.0.0 (2019-08-08)
 
diff --git a/src/utils/html.js b/src/utils/html.js
index 878cf3c3d..11f181504 100644
--- a/src/utils/html.js
+++ b/src/utils/html.js
@@ -223,7 +223,7 @@ u.calculateElementHeight = function (el) {
 
 u.getNextElement = function (el, selector='*') {
     let next_el = el.nextElementSibling;
-    while ((next_el instanceof Element) && !sizzle.matchesSelector(next_el, selector)) {
+    while (next_el !== null && !sizzle.matchesSelector(next_el, selector)) {
         next_el = next_el.nextElementSibling;
     }
     return next_el;
@@ -231,24 +231,24 @@ u.getNextElement = function (el, selector='*') {
 
 u.getPreviousElement = function (el, selector='*') {
     let prev_el = el.previousElementSibling;
-    while ((prev_el instanceof Element) && !sizzle.matchesSelector(prev_el, selector)) {
-        prev_el = prev_el.previousSibling
+    while (prev_el !== null && !sizzle.matchesSelector(prev_el, selector)) {
+        prev_el = prev_el.previousElementSibling
     }
     return prev_el;
 }
 
 u.getFirstChildElement = function (el, selector='*') {
     let first_el = el.firstElementChild;
-    while ((first_el instanceof Element) && !sizzle.matchesSelector(first_el, selector)) {
-        first_el = first_el.nextSibling
+    while (first_el !== null && !sizzle.matchesSelector(first_el, selector)) {
+        first_el = first_el.nextElementSibling
     }
     return first_el;
 }
 
 u.getLastChildElement = function (el, selector='*') {
     let last_el = el.lastElementChild;
-    while ((last_el instanceof Element) && !sizzle.matchesSelector(last_el, selector)) {
-        last_el = last_el.previousSibling
+    while (last_el !== null && !sizzle.matchesSelector(last_el, selector)) {
+        last_el = last_el.previousElementSibling
     }
     return last_el;
 }
@@ -284,7 +284,7 @@ u.hideElement = function (el) {
 
 u.ancestor = function (el, selector) {
     let parent = el;
-    while ((parent instanceof Element) && !sizzle.matchesSelector(parent, selector)) {
+    while (parent !== null && !sizzle.matchesSelector(parent, selector)) {
         parent = parent.parentElement;
     }
     return parent;
@@ -294,7 +294,7 @@ u.nextUntil = function (el, selector, include_self=false) {
     /* Return the element's siblings until one matches the selector. */
     const matches = [];
     let sibling_el = el.nextElementSibling;
-    while ((sibling_el instanceof Element) && !sibling_el.matches(selector)) {
+    while (sibling_el !== null && !sibling_el.matches(selector)) {
         matches.push(sibling_el);
         sibling_el = sibling_el.nextElementSibling;
     }