editing an image can result in intermediate sized images left over after the image is deleted

[pbiron]

Steps to reproduce:

1. set thumbnail_size to 150x150
2. upload a 300x300 image, e.g., foo.jpg
   • will result in /wp-content/uploads/foo-150x150.jpg being generated
3. edit the image and scale to 200x200
   • will result in something like /wp-content/uploads/foo-e1526583456941.jpg being generated
   • /wp-content/uploads/foo-150x150.jpg will still be present, since it is still a valid thumbnail for the scaled image
4. regenerate intermediate sized images (e.g., by calling ​wp_get_attachment_metadata() followed by ​wp_update_attachment_metadata(), which the ​Regenerate Thumbnails plugin does)
   • will result in something like /wp-content/uploads/foo-e1526583456941-150x150.jpg being generated
5. "Delete Permanently" the image

Check /wp-content/uploads and you will see that foo-150x150.jpg is still there.

[pbiron]

There are probably a number of ways to address this but my suggestion is:

1. in ​wp_save_image(), augment the _wp_attachment_backup_sizes postmeta to contain the info in the sizes portion of the wp_attachment_metadata postmeta
2. in ​wp_delete_attachment(), use that augmented info to delete the files that are currently not being deleted

[pbiron]

There are currently no unit tests for the creation/modification of the _wp_attachment_backup_sizes postmeta by wp_save_image(). So, before moving forward with a patch for this ticket I'm proposing these tests as benchmark on existing behavior. Add this file to /tests/phpunit/tests/ajax.

[pbiron]

This is a phpunit config file to run those tests in MediaEditBackupSizes.php that depend on IMAGE_EDIT_OVERWRITE being false (or are agnostic to its value). Add this file to /tests/phpunit and then run phpunit -c tests/phpunit/MeditEditBackupSizes.xml

[pbiron]

This is a phpunit config file to run those tests in MediaEditBackupSizes.php that depend on IMAGE_EDIT_OVERWRITE being true (or are agnostic to its value). Add this file to /tests/phpunit and then run phpunit -c tests/phpunit/MeditEditBackupSizesImageEditOverwrite.xml

[pbiron]

This is the 1st of several comments calling out specific questions in the unit tests.

I wrote tests for how scale and crop effect _wp_attachment_backup_sizes but not for rotate and flip because it doesn't seem to me that they were necessary as those operations produce the same mods on _wp_attachment_backup_sizes as crop does.

Can someone who knows the code better than I do confirm that tests for rotate and flip aren't necessary?

[pbiron]

Argh!!! I just discovered a MAJOR bug with the tests and found they are not testing what I thought they were testing. I'll upload another version when I get that bug fixed.

[pbiron]

This fixes the bug I just mentioned. Do not use MediaEditBackupSizes.php!!! The bug was that the $_REQUEST array wasn't being emptied before setting up each new request; as a result, the testScaleImageImageEditOverwrite() and testMultipleScaleImageImageEditOverwrite() were actually doing the crop from the previous test instead of the scale they were supposed to be doing and I had constructed the $expected value for that "incorrect" operation rather than what it should it should have been. This version corrects those tests as well as fixing _setUpRequest().

[pbiron]

We now return you to your regularly scheduled questions :-)

Does anyone think there is a need for a test that includes a scale and a crop on the same image?