TimberImageHelper::delete_generated_files doesn’t delete jpg files created through tojpg filter

[gchtr]

Expected behavior

TimberImageHelper::delete_generated_files() should automatically delete all generated image sizes when an attachment is deleted.

Actual behavior

Some JPG files are not deleted, when they were generated through tojpg Twig filter that was used on a PNG file.

Steps to reproduce behavior

1. Upload PNG image to Media Library.
2. Assign PNG to post as featured image.
3. Bring featured image into template through <img src="{{post.thumbnail.src|tojpg|resize(200, 200)}}">
4. Check if JPG file with dimensions 200x200 is present in wp-content/uploads folder.
5. Choose _Delete permanently_ on uploaded PNG in Media Library.
6. Check for JPG file with dimensions 200x200 still present in wp-content/uploads folder.

What version of WordPress, PHP and Timber are you using?

WordPress 4.4.2, PHP 5.6.10, Timber 0.22.5

How did you install Timber?

Upgraded to newest version via plugin updater in WordPress.

[jarednova]

@gchtr: thanks for filing this detailed issue (and using the issue template, it really helps us zero-in on the problem quickly and provide a patch). @connorjburton made changes to the code and submitted a PR in #897 that resolves the issue. Thanks to you both for making the fix happen!

[gchtr]

@jarednova @connorjburton Thanks for the fix! I think the issue template works really well, for both sides.