From: Kevin Bracey <kevin@bracey.fi>
Date: Thu, 31 May 2018 14:54:07 GMT
Subject: Re: Weird revision walk behaviour
Message-ID: <28359a94-e584-a963-428d-2cf11f2cb895@bracey.fi>
In-Reply-To: <20180531054355.GA17344@sigill.intra.peff.net>

On 31/05/2018 08:43, Jeff King wrote:
>
> If there are zero parents (neither relevant nor irrelevant), is it still
> TREESAME? I would say in theory yes.

Not sure - I think roots are such a special case that TREESAME 
effectively doesn't matter. We always test for roots first.
>   So what I was proposing would be to
> rewrite the parents to the empty set.
That feels a bit radical - I believe we need to retain (some) parent 
information for modes that show it (eg the dangling unfilled circles in 
gitk). And making it a root I think could cause other problems with 
making it look like we have a disjoint history. I believe the next 
simplification step may be trying to follow down to the common root.
> What next here? It looks like we have a proposed solution. Do you want
> to try to work up a set of tests based on what you wrote earlier?
I was hoping Gábor would carry on, as he's made a start... I was just 
planning to back-seat drive.
> I'd also love to hear from Junio as the expert in this area, but I think
> he's been a bit busy with maintainer stuff recently. So maybe I should
> just be patient. :)
>
Likewise - I have been quite deep into this, but it was a quite short 
window of investigation a long time ago, and I've not looked at it 
since. Would like input from someone with more active knowledge.

Kevin