6574 filenames

[pdurbin]

What this PR does / why we need it:

Several bugs were found while investigating filenames:

• From the "edit metadata for files" page, you could give files the same name.
• Via API, it was possible to give rename files to have the same name.
• Via API, it was possible to "move" files to directory with a file that has the same name, creating a duplicate.

Which issue(s) this PR closes:

Closes #6574

Special notes for your reviewer:

Methods are in IngestUtil because that's where similar methods are found. Previous methods were focused on returning a unique filename such as README-1.md. The new methods are focused on identifying duplicates.

Suggestions on how to test this:

Try exercising the bugs above on develop vs. this branch. The API to use is this one, passing "label" and "directoryLabel" in the JSON: http://guides.dataverse.org/en/4.20/api/native-api.html#updating-file-metadata

Does this PR introduce a user interface change?:

Yes, if you try to rename a file to create a naming conflict, you will see an error like this:

Is there a release notes update needed for this change?:

I don't believe so.

Additional documentation:

None.

[coveralls]

Coverage decreased (-0.01%) to 19.614% when pulling e79280b on 6574-filenames into 5285381 on develop.

[sekmiller]

suggested some code consolidation. overall looks good.

[sekmiller]

would it be possible to combine this with findDuplicateFilenames so that the UI and api are using the same method? You're passing in the filemetadata list from the dataset version which is the param for findDuplicateFilenames

[pdurbin]

@sekmiller good idea. Fixed in 8d6a5c8.

[pdurbin]

I addressed code review in 8d6a5c8 (reduced duplicate code). I also added the new test class to the API test suite in dc77ac1 and merged the latest from develop.