Re: [PATCH 5/6] status: do not depend on flaky reflog messages

From: Ramkumar Ramachandra <artagnon@gmail.com>
Date: Jun 14, 2013, 21:36 UTC
Message-ID: <CALkWK0==Phbe-9QaOa3jkYMEvxb6F3kypRkk9RbzrLco-HkHKw@mail.gmail.com>
In-Reply-To: <7vsj0kpsb0.fsf@alter.siamese.dyndns.org>

Junio C Hamano wrote:

Show 6 quoted lines

> If you first update "git checkout" so that it will pay attention to
> a custom reflog-action exported by Porcelain scripts that may want
> to internally use it to flip branches (and without a custom one, it
> will still record "checkout: moving from A to B"), without exporting
> custom reflog-action from "rebase" and other Porcelain scripts, that
> would not affect any externally visible behaviour.

rebase already sets a custom reflog-action; in fact, 'set_reflog_action rebase' is executed after it sources sh-setup. I have to go out of my way to deliberately unset it before every checkout invocation to avoid breaking all the tests in t/status-help. Most unnatural way to go about writing a series, if you ask me.

Show 8 quoted lines

> Tests modified by b397ea4863a1 (status: show
> more info than "currently not on any branch", 2013-03-13) do change
> the original "# Not currently on any branch" to "detached at", but I
> do not think b397ea4863a1 _wanted_ to say where the $onto commit was
> during the rebase (or was it?), so if they have to change to
> "detached from", I do not think it is a problem at all.  I think it
> is very sane to update these selected "detached at" to "detached
> from" as needed.

... and you have missed the point yet again.

I previously wrote:

Show 7 quoted lines

> I'd just like to point out quickly that I first attempted to write 6/6
> without this patch.  It is absolutely impossible, because the
> "detached HEAD from/to" messages no longer make any sense when
> checkout starts respecting GIT_REFLOG_ACTION.  At that point, I'm was
> just monkeying around the trash-directory running describes to somehow
> try and make the expected output equal to the actual output.  There
> was no method to the madness, and I was literally losing my mind.

Let me try and explain this once again: to determine "HEAD detached from/to", wt-status must look for a previous "checkout: " message in the reflog. Since a rebase no longer executes a checkout, the "detached HEAD from" message no longer has anything to do with the rebase itself; it is completely _random_ and _incidental_, based on what checkout operation was executed last (eg. in a previous test). To change the "detached HEAD to" messages to "detached HEAD from" messages, I have to turn myself into a monkey that goes around running describes on the test-directory. After enduring hours of this mind-numbing job, the final result will be a terrible mess; tests can no longer be added, removed, reordered, or even tweaked. Everything depends on the exact ordering of the tests, and the incidental checkout invocations they contain.

> That would be a sensible compromise

How is it a compromise?  It is most uncompromising.

Show 10 quoted lines

> because we do not want to see
> either "detached at" or "detached from" during "rebase" in the
> longer term.  We would rather want to see the message start with
> something like
>
>         # Rebasing X on top of Y (23 commits remaining to be replayed)
>
> which is under discussion in a separate thread lately.  The change
> to expected output (i.e. "detached at" to "detached from") will have
> to be changed again in that separate topic.

Orthogonal. I want checkout-dash now, and I should not have to be asked to do something as unrelated as redoing 'git status' output to get what I want.

Since you have made it clear that you will defend every bit of b397ea against all odds, and since I want checkout-dash now, we have to do something. I have a proposal: I will smudge the first line of the 'git status' output, before comparing it to make tests pass. Never mind that the line is incidental and Wrong; since I have no say in the matter, I will just sidestep the issue. I don't use the long-form 'git status' anyway, and am never going to see this ugliness. We both win. Okay?