The helper in question complicates the logic of sstable_directory::process() by making garbage collection differently for sstables deleted "atomically" and deleted "one-by-one". Also, the code that deletes sstables one-by-one and uses remove_by_toc_name() renders excessive TOC file reading, because there's sstable object at hand and it had all_components() ready for use.
Surprisingly, there was no test for the deletion-log functionality. This PR adds one. The test passes before the g.c. and regular unlink fix, and (of course) continues passing after it.
Closesscylladb/scylladb#16240
* github.com:scylladb/scylladb:
sstables: Drop remove_by_name()
sstables/fs_storage: Wipe by recognized+unrecognized components
sstable_directory: Enlight deletion log replay
sstables: Split remove_by_toc_name()
test: Add test case to validate deletion log work
sstable_directory: Close dir on exception
sstable_directory: Fix indentation after previous patch
sstable_directory: Coroutinize delete_with_pending_deletion_log()
test: Sstable on_delete() is not necessarily in a thread
sstable_directory: Split delete_with_pending_deletion_log()
8fa2e3ad2a