Ember.js 3.28 and class based template compilation deprecation

We’re upgrading Ember.js from version 3.16 to version 3.28. We’re getting an error that looks like:

Using class based template compilation plugins is deprecated, please update to the functional style

I found this section on the deprecations web page, but it doesn’t give more information. Any idea what this could mean? When I’m running ember test, the output is flooded with it, can barely read anything. Thank you.

[m0glan]

I really appreciate the effort and I’m sure it will help other confused Ember newbies like me. I will close this issue since I restarted the upgrade process from scratch and didn’t come across it anymore.

Thanks a lot!

[bertdeblock]

That one seems to come from ember-cli-template-lint.

You can always use Ember Observer’s code search to find things like this: https://emberobserver.com/code-search?codeQuery=RemoveConfigurationHtmlCommentsPlugin.

The solution here would be to remove ember-cli-template-lint and use ember-template-lint directly instead. ember-cli-template-lint is deprecated and won’t be updated to fix this.

But if you are updating via ember-cli-update, normally this should’ve been taken care of via blueprint updates.