On Tue, Jul 27, 2021 at 8:14 PM Jerry Zhang <jerry@xxxxxxxxxx> wrote: > > Certain invocations of "git apply --3way" > will print error messages even though git > is able to fall back on apply_fragments and > apply the patch successfully with a return > value of 0. To fix, return early from > try_threeway() in the following cases: > > When the patch is a rename and no lines have > changed. In this case, "git diff" doesn't > record the blob info, so 3way is neither > possible nor necessary. > > When the patch is an addition and there is > no add/add conflict, i.e. direct_to_threeway > is false. In this case, threeway will fail > since the preimage is not in cache, but isn't > necessary anyway since there is no conflict. > > Only error messaging is affected and other > behavior does not change. > > Signed-off-by: Jerry Zhang <jerry@xxxxxxxxxx> > --- > V1->V2: rebase onto master and rerun tests > > I think I addressed previous comments. What > are the next steps for this patch? > > apply.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/apply.c b/apply.c > index 44bc31d6eb..fb321c707b 100644 > --- a/apply.c > +++ b/apply.c > @@ -3560,7 +3560,9 @@ static int try_threeway(struct apply_state *state, > > /* No point falling back to 3-way merge in these cases */ > if (patch->is_delete || > - S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode)) > + S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode) || > + (patch->is_new && !patch->direct_to_threeway) || > + (patch->is_rename && !patch->lines_added && !patch->lines_deleted)) > return -1; > > /* Preimage the patch was prepared for */ > -- > 2.32.0.1314.g6ed4fcc4cc > Any updates on this patch? I had addressed the previous comment in this thread in a different patch "apply: adjust messages to account for --3way changes" that was already merged in a while ago. I originally intended this to mainly fix print message behavior, but while testing I found that it also fixed a separately reported issue from this thread: https://www.spinics.net/lists/git/msg421481.html. I probably owe an update / refresher on why I originally submitted these features in the first place. I've written a tool for branchless / patch stack based code review and development w/github. The core of this is a mechanism that can cherry-pick commits without touching the cache or working tree by using "git apply --cached --3way" with a custom index file. We've been using this internally with a custom built git for a while now and gotten pretty good feedback. We'd like to open source this tool soon, and it'd be nice if our open-source users (eventually) don't need to build git themselves :).
