Re: [RFC] Replace rebase with filtering

> Steven Grimm wrote:
> > Johannes Schindelin wrote:
> > > I had the impression that the use of "--ignore-if-in-upstream" in
> > > git-rebase avoids exactly this case: re-applying changes which are already
> > > in upstream.  
> > Where's that option documented? The manpage makes no mention of it at all.
> 
> Ah, okay, poking around in the git-rebase source, I see you mean that
> git-format-patch is called with that option. Gotcha. The problem is that after
> a rebase, the revisions in question *aren't* in the upstream. Here's my
> understanding of why. Say I have this in my integration repository:
> 
> a---b---c---d (master)
> \
>  e---f---g   (integration)
> 
> Now, I rebase the integration branch onto master:
> 
> a---b---c---d
>             \
>              e'---f'---g'
> 
> The problem is that, since e' contains all the changes in e *and* in 
> b/c/d, it does not have the same SHA1 as the original e revision, nor in 
> fact the same hash as any of the revisions in the pre-rebase tree. And 
> after rebase succeeds, it wipes the original e, f, and g from the 
> history of the integration branch.