Regression: block attribute classes end up on block title as well

Patch from the MR.

Chris Burge → made their first commit to this issue’s fork.

@solideogloria - Thanks for quickly catching this bug. We didn't have test coverage for preservation of existing classes. I just pushed a commit to the MR to add test coverage.

Bug fix is released in 2.1.3.

Shouldn't the tests also check that no extra (undesirable) classes are added? That was the issue in this case.

@solideogloria - It wasn't that classes were being added per se. The regression was that the existing classes for a block's attributes were being assigned as its title_attributes and content_attributes, too, due to unintentional hard-coding. Your MR fixed this bug in the layout_builder_component_attributes_preprocess_block() function:

-       $existing_classes = $variables['attributes']['class'] ?? [];
+       $existing_classes = $variables[$attribute_name]['class'] ?? [];

Test coverage was added to the MR before committing: https://git.drupalcode.org/project/layout_builder_component_attributes/-...

If you revert the aforementioned line of code and run tests, they'll fail now. Implementing a before/after check would probably be overkill, but if you want to take a stab at it, feel free to open another MR.

I saw the test coverage added; I just didn't understand how that would have caught the issue. I see now. Thanks.

Automatically closed - issue fixed for 2 weeks with no activity.