Ember 3.17 - helper re-computation in {{each}}

[22a]

Since ember-source 3.17.0-beta.1, helpers rendered inside an {{each}} block are re-computed/re-rendered when the passed list changes by reference. In these scenarios, the existing helper content is removed from the DOM and re-appended.

This has led to a few issues in our app with event targets not being present in the DOM by the time the event has propagated to any global event listeners (on the document/window).

Minimal reproduction

I’ve put together an reproduction of this in a component by invoking ember-inline-svg inside an {{each}} block in a fresh app: https://github.com/22a/ember-helper-re-render-repro

• my-component.hbs
• my-component.js

The example is a little contrived in how it induces the {{each}} re-evaluation, but it does illustrate that, since 3.17.0 (through present: 3.18.1), helpers are being torn down and re-appended to the DOM where components / elements don’t.

<=3.16.8

>= 3.17.0-beta.1

While I show a click on a path in both screenshots above it happens equally to the svg node - I can simplify this reproduction further to a helper that simply inserts a div if that would be helpful.

[rwjblue]

I believe this is a duplicate of an issue that was fixed in 3.18.1. Can you update and confirm?

[rwjblue]

Hmm, sorry, I see now that you mentioned that the demo still shows the described behavior on 3.18.1.

[rwjblue]

This was fixed in glimmerjs/glimmer-vm#1100, which is released in 3.19.0. I confirmed in the reproduction you provided.