Fix crash when deleting compositions / rework delete function
If you create a composition, then delete it, if you try to delete again when the list is empty there will be an index error and Krita will crash.
I've reworked the logic so that the delete function will no longer try to set the current index to a nonexistent one. (checking for validity is not good enough, index comes back as valid even if not present in the view, an issue that goes over my head)
I also changed the logic so that the currently selected composition will move to the next available one if the last composition in the list is deleted. (Previously, none would be selected)
Test Plan
Create and delete multiple compositions in various orders, including trying to delete when no compositions exist in the list.
Formalities Checklist
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I confirmed this builds. -
I confirmed Krita ran and the relevant functions work. -
I tested the relevant unit tests and can confirm they are not broken. (If not possible, don't hesitate to ask for help!) -
I made sure my commits build individually and have good descriptions as per KDE guidelines. -
I made sure my code conforms to the standards set in the HACKING file. -
I can confirm the code is licensed and attributed appropriately, and that unattributed code is mine, as per KDE Licensing Policy. -
Does the patch add a user-visible feature? If yes, is there a documentation MR ready for it at Krita Documentation Repository?
Reminder: the reviewer is responsible for merging the patch, this is to ensure at the least two people can build the patch. In case a patch breaks the build, both the author and the reviewer should be contacted to fix the build. If this is not possible, the commits shall be reverted, and a notification with the reasoning and any relevant logs shall be sent to the mailing list, kimageshop@kde.org.