It wrongly keep the incomplete backup file when fails

[ghost]

Describe the bug
Hi,
when disk is full it correctly fails but it still keep the incomplete backup file and it also delete the oldest backup, so after many days of failed backups you are kept just with broken files since all good backups will be gone.

Can it be fixed please?

To Reproduce
Steps to reproduce the behavior:

1. Execute a backup when disk is full

Expected behavior
When it fails I expect that it delete the broken backup file to avoid wasting space and do not delete the oldest one since the new is failed.

System (please complete the following information):

• OS: Linux