threads / discuss / 51457
Subject: `@` alias for `HEAD` not working in `git push -u origin @`
Hello!
I learned today that `@` is a shortcut for `HEAD`. From `git help reivisions`:
@ alone is a shortcut for HEAD.
However, when I tried to use it in a command I frequently use, I got an error:
$ git push -u origin @
fatal: invalid refspec '@'I'm running git version 2.22.0 on Linux.
Is this a bug, or have I misunderstood how this is supposed to work?
Cheers, Mark
brian m. carlsonRe: `@` alias for `HEAD` not working in `git push -u origin @`
On 2019-07-10 at 05:06:08, Mark Florian wrote:
> Hello! > > I learned today that `@` is a shortcut for `HEAD`. From `git help reivisions`: > > @ alone is a shortcut for HEAD. > > However, when I tried to use it in a command I frequently use, I got an error: > > $ git push -u origin @ > fatal: invalid refspec '@' > > I'm running git version 2.22.0 on Linux. > > Is this a bug, or have I misunderstood how this is supposed to work?
This is a bug. If the destination side of a refspec is omitted, and the source side resolves to a ref starting with "refs/heads/" or "refs/tags/" (which I expect it does here), then that ref is used as the destination.
I submitted a patch at [0], but it was decided not to pick it up. If Junio and the list decide that it's wanted, I'm happy to resend or revise and resend.
[0] https://public-inbox.org/git/20180729192803.1047050-1-sandals@crustytoothpaste.net/
-- brian m. carlson: Houston, Texas, US OpenPGP: https://keybase.io/bk2204
Johannes SchindelinRe: `@` alias for `HEAD` not working in `git push -u origin @`
Hi brian,
On Wed, 10 Jul 2019, brian m. carlson wrote:
> On 2019-07-10 at 05:06:08, Mark Florian wrote: > > > > I learned today that `@` is a shortcut for `HEAD`. From `git help reivisions`: > > > > @ alone is a shortcut for HEAD. > > > > However, when I tried to use it in a command I frequently use, I got an error: > > > > $ git push -u origin @ > > fatal: invalid refspec '@' > > > > I'm running git version 2.22.0 on Linux. > > > > Is this a bug, or have I misunderstood how this is supposed to work? > > This is a bug. If the destination side of a refspec is omitted, and the > source side resolves to a ref starting with "refs/heads/" or > "refs/tags/" (which I expect it does here), then that ref is used as the > destination. > > I submitted a patch at [0], but it was decided not to pick it up. If > Junio and the list decide that it's wanted, I'm happy to resend or > revise and resend. > > [0] https://public-inbox.org/git/20180729192803.1047050-1-sandals@crustytoothpaste.net/
After reading that thread, I come to the conclusion that it was not so much a decision not to pick it up, but more like a falling between the cracks.
I would be in favor of this patch.
Since I have your attention and since I am interested in a related issue (when I wanted to propose a GSoC mini project to let `git fetch <remote> @` expand the `@` to the current (local) branch name, Matthieu Moy pointed out that `git fetch --current <remote>` might be a better UI): what does your patch do with `git fetch`'s refspec arguments?
Ciao, Dscho
brian m. carlsonRe: `@` alias for `HEAD` not working in `git push -u origin @`
On 2019-07-11 at 09:46:26, Johannes Schindelin wrote:
> After reading that thread, I come to the conclusion that it was not so > much a decision not to pick it up, but more like a falling between the > cracks. > > I would be in favor of this patch.
I think there was some later follow-up in a different thread (one of the "What's cooking" threads) that expressed reservations about it, but I can't find that thread right now.
Regardless, if there's interest, I can certainly resend and see how folks on the list feel about it.
> Since I have your attention and since I am interested in a related issue > (when I wanted to propose a GSoC mini project to let `git fetch <remote> > @` expand the `@` to the current (local) branch name, Matthieu Moy > pointed out that `git fetch --current <remote>` might be a better UI): > what does your patch do with `git fetch`'s refspec arguments?
I haven't checked. I believe it would resolve "git fetch origin @" to "git fetch origin HEAD" and "git fetch origin @:refs/heads/master" to "git fetch origin HEAD:refs/heads/master".
I can add some additional tests for this case, although I'm not especially sure that it provides useful behavior people will want.
-- brian m. carlson: Houston, Texas, US OpenPGP: https://keybase.io/bk2204
Johannes SchindelinRe: `@` alias for `HEAD` not working in `git push -u origin @`
Hi brian,
On Thu, 11 Jul 2019, brian m. carlson wrote:
> On 2019-07-11 at 09:46:26, Johannes Schindelin wrote: > > > Since I have your attention and since I am interested in a related issue > > (when I wanted to propose a GSoC mini project to let `git fetch <remote> > > @` expand the `@` to the current (local) branch name, Matthieu Moy > > pointed out that `git fetch --current <remote>` might be a better UI): > > what does your patch do with `git fetch`'s refspec arguments? > > I haven't checked. I believe it would resolve "git fetch origin @" to > "git fetch origin HEAD" and "git fetch origin @:refs/heads/master" to > "git fetch origin HEAD:refs/heads/master".
That sounds like a sane behavior, as `@` on the "src" side of a refspec that tries to fetch from a remote repository should probably not expand to a _local_ branch.
> I can add some additional tests for this case, although I'm not > especially sure that it provides useful behavior people will want.
Nah, from my side this is not necessary.
Ciao, Dscho
Jeff KingRe: `@` alias for `HEAD` not working in `git push -u origin @`
On Wed, Jul 10, 2019 at 11:39:37PM +0000, brian m. carlson wrote:
> This is a bug. If the destination side of a refspec is omitted, and the > source side resolves to a ref starting with "refs/heads/" or > "refs/tags/" (which I expect it does here), then that ref is used as the > destination. > > I submitted a patch at [0], but it was decided not to pick it up. If > Junio and the list decide that it's wanted, I'm happy to resend or > revise and resend. > > [0] https://public-inbox.org/git/20180729192803.1047050-1-sandals@crustytoothpaste.net/
I see I was cc'd on that original, but I don't remember ever reading it. It seems like a sane enough idea to me.
Although I did notice that you mentioned there:
> I probably type "git push upstream HEAD" from five to thirty times a > day
I find I do that rarely, because I have:
[push] default = current
and in a triangular workflow, I have:
[remote] pushDefault = upstream
So "git push" without arguments typically does the same thing for me.
Not an argument against your patch, but just something you might find useful.
-Peff
Junio C HamanoRe: `@` alias for `HEAD` not working in `git push -u origin @`
Jeff King <peff@peff.net> writes:
> On Wed, Jul 10, 2019 at 11:39:37PM +0000, brian m. carlson wrote: > >> This is a bug. If the destination side of a refspec is omitted, and the >> source side resolves to a ref starting with "refs/heads/" or >> "refs/tags/" (which I expect it does here), then that ref is used as the >> destination. >> >> I submitted a patch at [0], but it was decided not to pick it up. If >> Junio and the list decide that it's wanted, I'm happy to resend or >> revise and resend. >> >> [0] https://public-inbox.org/git/20180729192803.1047050-1-sandals@crustytoothpaste.net/ > > I see I was cc'd on that original, but I don't remember ever reading it. > It seems like a sane enough idea to me.
I see I was also on the cc list; I am not sure what I thought about the patch (i.e. implementation, not the desire to use '@' in the context in place for "HEAD") back then.
Now I read it with everything I thought forgotten, I see two potential issues:
- Any error message downstream will mention "HEAD" and there won't be a trace of it originally being an "@" sign. It may not be a problem, especially for those who _KNOW_ that they should be typing HEAD but can type "@" instead, but I am not sure what to do those who do not know much about "HEAD" and start from "@" (by the way, it is one reason why I do not like encouraging "@", especially in introductory text).
- The code should update llen to 4; right now the remainder of the function does not use the variable in a way that the discrepancy of replacing "@" with "HEAD" without updating llen matters, but relying on the shape of the code that happens to exist right now is a bad code hygiene.
Other than that, the patch looks sensible to me.
> Although I did notice that you mentioned there: > >> I probably type "git push upstream HEAD" from five to thirty times a >> day > > I find I do that rarely, because I have: > > [push] > default = current > > and in a triangular workflow, I have: > > [remote] > pushDefault = upstream > > So "git push" without arguments typically does the same thing for me. > > Not an argument against your patch, but just something you might find > useful.
That's a helpful tangent. Thanks.