Add partial cloning support?

[nafiz1001]

Would be nice if straight supported partial cloning as an alternative to shallow cloning. That way contributing to upstream should be easier and cloning size should be small. We could provide options such as "Blobless" or "Treeless". You can check this link for more detail: https://github.blog/2020-12-21-get-up-to-speed-with-partial-clone-and-shallow-clone/.

[progfolio]

Would be nice if straight supported partial cloning as an alternative to shallow
cloning. That way contributing to upstream should be easier and cloning size
should be small.
We could provide options such as "Blobless" or "Treeless". You
can check this link for more detail:
https://github.blog/2020-12-21-get-up-to-speed-with-partial-clone-and-shallow-clone/.

Thanks for the suggestion.

@raxod502:
One thing we'll have to keep in mind if we do offer these options is that they are available in git v2.20 (released late 2018), while we support a min Emacs version of 25.1 (released 2016-09-17).

Personally, I'd be in favor of bumping our minimum support to 27.1 (I believe that's what Doom requires), but that's a separate issue

[raxod502]

Well, the versions of Git and Emacs aren't necessarily in lock-step with one another, so I think we have a fair amount of freedom one way or another about the minimum version constraints. Either way, we'll of course need to continue supporting old Git versions for a long time.

I tend to think that we should be very conservative with dropping support for old Emacs versions. After all, straight.el is the foundation of the package ecosystem, and essentially acts as a required dependency for every package. No objection to increasing the minimum version, but I probably would not go all the way from 25.1 to 27.1 right now (that's a 4-year gap).