TYPO3 Core

Currently, when overwriting a file, we have this situation:

1. When copying a file over another file, everything is fine
2. When moving a file over another file, everything is fine if only one of them (or none) is indexed
3. When the new file is freshly uploaded, everything is fine

So there basically is one critical case: When two index records would point to the same location after changing them (this already fails in the indexer when detecting files moved outside of TYPO3). Currently there is no logic to resolve such conflicts, but we should definitely have it.

In general, the simplest approach would be to take the most recently updated index entry and change the references to all other conflicting files to point to this uid. However, the infrastructure for these operations is still missing (e.g. in the repository)