Re: [PATCH v20 0/7] branch: delete-merged

On Wed, Jul 22, 2026 at 3:39 PM Phillip Wood <[email protected]> wrote:
>
> Hi Harald
>
> On 22/07/2026 08:10, Harald Nordgren via GitGitGadget wrote:
> > Delete branches that have already been merged on upstream.
> >
> > Changes in v20:
> >
> >   * Protect branches transitively required by a surviving local upstream
> >     stack. Traverse upstream chains once and defer delete-set mutation until
> >     traversal completes.
> >   * Make stacked-branch handling independent of ref iteration order and
> >     update the documentation accordingly.
> >   * Clarify variable names with regards to branch names (short) to reduce
> >     confusion.
>
> I'm having a hard time reading the range diff due to the renaming of the
> members of "struct stacked_branch_data". Can you explain what has
> changed in the logic to protect branches that are upstreams of unmerged
> branches and why please? In particular why wasn't sufficient to stop
> removing the members of "spared" from "deletable" in
> spare_stacked_base() and remove them after refs_for_each_branch_ref()
> has returned instead.

Hmm. The main idea is to bite the bullet and actually traverse the
graph since it didn't seem possible to finish the job correctly in a
single pass anotherwise which I'm trying to demonstrate with

    test_expect_success '--delete-merged keeps the upstream chain of a
surviving branch' '

It becomes a bit like whack-a-mole when Junio asks me to clarify the
code and now you cannot review it because of that. I'm still not
friends with range-diff even after using it for some time, I agree
that the diff v19...v20 doesn't look very inviting.


Harald