From: Martin von Zweigbergk <martinvonz@google.com>
Date: Thu, 16 Oct 2025 17:12:21 GMT
Subject: Re: [PATCH] BreakingChanges: say that `git diff X..Y` syntax will be removed in 3.0
Message-ID: <CAESOdVCQR=z95MK1oHZO4_iBXS8Z9uz4Fs0gDDX+BfaG9_3=ag@mail.gmail.com>
In-Reply-To: <d47e137b-c34d-49c9-bf45-226cbcdba416@app.fastmail.com>

On Thu, 16 Oct 2025 at 10:02, Kristoffer Haugsbakk
<kristofferhaugsbakk@fastmail.com> wrote:
>
> On Thu, Oct 16, 2025, at 18:38, Martin von Zweigbergk wrote:
> > On Thu, 16 Oct 2025 at 06:44, Junio C Hamano <gitster@pobox.com> wrote:
> >>[snip]
> >>
> >> The same for "git checkout master..."  that detaches HEAD at the
> >> fork point of the current topic (so that I can "git am" in a new
> >> iteration of patches on top).
> >
> > I couldn't get this to work:
> >
> > $ git checkout main... --
> > fatal: invalid reference: main...
>
> `git checkout X...` works for me.  Apparently it is this part of the
> doc: “As a special case, you may use <rev-a>...<rev-b> [...]”

Oh, I think I know what the problem is. The reason I tried it was that
I was curious how it would behave when there are multiple merge bases,
so I had set up a repo like that. Then I got this:

```
$ git checkout main...
error: pathspec 'main...' did not match any file(s) known to git
$ git checkout main... --
fatal: invalid reference: main...
```

I didn't expect those messages to mean "the common ancestor is
ambiguous" so I didn't think to try with an unambiguous common
ancestor.

>
> >
> > But don't worry about it. I think your point about there being other
> > commands that support the triple-dot syntax is still valid.
> >
> >>  As the syntax "git diff master..."
> >> is symmetric with it, if one were to change, both should change to
> >> the same.
> >[snip]