Cache non-existence of files or completeness of repo (#986)
* Cache non-existence of files or completeness of repo
* Revert complete and add tests
* Remove dupe test and quality
* Remove debugging statements
Co-authored-by: Lucain <lucainp@gmail.com>
* Address review comments
* Group tests together
* Quality
* FIX touch in case of subdirectory
* refactored duplicated test test_file_downloaded_in_cache
* fix writing new ref if ref changed
Co-authored-by: Lucain <lucainp@gmail.com>