Derrick Stolee <derrickstolee@xxxxxxxxxx> writes: > On 6/21/2022 7:30 PM, Victoria Dye wrote: >> Shaoxuan Yuan wrote: >>> But I think it worth discuss if we should implement in-cone to >>> out-of-cone move, since it will be nice (naturally) to have it working. >>> >>> However, I noticed this from the mv man page: >>> >>> "In the second form, the last argument has to be an existing directory; >>> the given sources will be moved into this directory." >>> >>> I think trying to move out-of-cone, the last argument has to be an non-existent >>> directory? I'm a bit confused: should we update some of mv basic logic to >>> accomplish this? >>> >> >> I suspect this requirement is related to the POSIX 'mv' [1] (and >> corresponding 'rename()', used in 'git mv'), which also requires that the >> destination directory exists. I personally don't think this requirement >> needs to apply to 'git mv' at all, but note that changing the behavior would >> require first creating the necessary directories before calling 'rename()'. >> >> As a more conservative solution, you could do the parent directory creation >> *only* in the case of moving to a sparse contents-only directory (using >> something like the 'check_dir_in_index()' function you introduced to >> identify). >> >> I'm also interested in hearing what others have to say, especially regarding >> historical context/use cases of 'git mv'. >> >> [1] https://pubs.opengroup.org/onlinepubs/9699919799/utilities/mv.html > > I wanted to reply here to maybe get more attention on this point. > > My personal opinion is that `git mv` should move to the location requested, > even if it requires adding parent directories. Changing that behavior might > need to come as its own topic, before doing the in-cone-to-out-of-cone work. > Knowing if this behavior can change (or must stay the same) informs how that > sparse case will work. When a particular checkout excludes directory, say, Documentation/, from its cone of interest, we may not have that directory in the working tree. In such a scenario, if you did $ git mv new.txt Documentation/technical/ the index may not even know if "Documentation/" (which most likely is represented as a sparse "tree entry in the index") has the "technical" subdirectory in it, so it may have to expand it on-demand. I do not have an objection against making it easier for users to do this. As part of its implementation, you may have to do an equivalent of "mkdir -p Documentation/technical/" before you can even materialize the "new.txt" file in the directory. I do not think that breaks the parallel to POSIX "mv" in that case, as Documentation/technical/ is *NOT* really a destination directory that does not exist. Conceptually, the directory (and all the directories in the full tree) exists---it is just the sparse-checkout is hiding it from the view. A corollary to the above is what should happen when you did $ git mv new.txt Documentation/no-such-directory/ i.e. you try to do a move that would fail even if you weren't using the sparse-checkout feature. I think that *SHOULD* fail, if we wanted to be parallel to what POSIX "mv" does. Thanks.
