On Wed, May 10, 2017 at 6:46 AM, Mike Hommey <m...@glandium.org> wrote: > On Wed, May 10, 2017 at 12:33:44AM -0400, Jeff King wrote: >> On Tue, May 09, 2017 at 09:22:11PM -0700, Shawn Pearce wrote: >> >> > > Hmm. That makes sense generally, as the request should succeed. But it >> > > seems like we're creating a client that will sometimes succeed and >> > > sometimes fail, and the reasoning will be somewhat opaque to the user. >> > > I have a feeling I'm missing some context on when you'd expect this to >> > > kick in. >> > >> > Specifically, someone I know was looking at building an application >> > that is passed only a SHA-1 for the tip of a ref on a popular hosting >> > site[1]. They wanted to run `git fetch URL SHA1`, but this failed >> > because the site doesn't have upload.allowtipsha1inwant enabled. >> > However the SHA1 was clearly in the output of git ls-remote. >> >> OK. So this is basically a case where we expect that the user knows what >> they're doing. >> >> > For various reasons they expected this to work, because it works >> > against other sites that do have upload.allowtipsha1inwant enabled. >> > And I personally just expected it to work because the fetch client >> > accepts SHA-1s, and the wire protocol uses "want SHA1" not "want ref", >> > and the SHA-1 passed on the command line was currently in the >> > advertisement when the connection opened, so its certainly something >> > the server is currently willing to serve. >> >> Right, makes sense. I wondered if GitHub should be turning on >> allowTipSHA1InWant, but it really doesn't make sense to. We _do_ hide >> some internal refs[1], and they're things that users wouldn't want to >> fetch. The problem for your case really is just on the client side, and >> this patch fixes it. > > More broadly, I think it is desirable that any commit that can be > reached from public refs can be fetched by an explicit sha1 without > allowTipSHA1InWant.
Just a side question, what are the people who use this feature using it for? The only thing I can think of myself is some out of band ref advertisement because you've got squillions of refs as a hack around git's limitations in that area. Are there other use-cases for this? All the commits[1] that touched this feature just explain what, not why. 1. git log --reverse -p -i -Gallowtipsha1inwant
