Re: [PATCH v2 2/3] blame: add the ability to ignore commits and their changes

From: Barret Rhoden <brho@google.com>
Date: Jan 22, 2019, 15:26 UTC
Message-ID: <20190122102601.24426c8e@brho.roam.corp.google.com>
In-Reply-To: <f5170cb1-4109-4ae3-7722-8e3b62fb0b92@web.de>

On 2019-01-20 at 19:19 René Scharfe <l.s.r@web.de> wrote:

Show 17 quoted lines

> Am 17.01.2019 um 21:29 schrieb Barret Rhoden:
> > The blame_entry will get passed up the tree until we find a commit that
> > has a diff chunk that affects those lines.  If an ignored commit added
> > more lines than it removed, the blame will fall on a commit that made a
> > change nearby.  There is no general solution here, just a best-effort
> > approach.  For a trivial example, consider ignoring this commit:
> >
> > Z: "Adding Lines"
> >  foo
> > +No commit
> > +ever touched
> > +these lines
> >  bar  
> 
> Wouldn't it make more sense to assign such lines to unknown, perhaps
> represented by an all-zero commit ID, instead of blaming a semi-random
> bystander?

I don't know if we can algorithmicly determine whether or not an assignment was the commit the user wanted. Maybe we could add a set of heuristics, like "any diff hunk that only added", as in my example. Maybe if count_a == 0 in blame_chunk_cb, that would work for that case; I'm not too familiar with that code.

Either way, in my next commit I provide the option to mark the commit
with a '*', which could serve the same purpose as the all-zero commit
ID: flag the commit so the user knows it might not be correct.

Barret