Thanks for the comments! I've updated v3 with the changes. Let me know if you have any more thoughts on whether to block / warn the user before clobbering their cache. On Mon, Apr 5, 2021 at 3:46 PM Junio C Hamano <gitster@xxxxxxxxx> wrote: > > Jerry Zhang <jerry@xxxxxxxxxx> writes: > > > Subject: Re: [PATCH V2] git-apply: Allow simultaneous --cached and --3way options > > s/Allow/allow/ (cf. "git shortlog --no-merged" output for recent examples) > > > Previously, --cached and --3way were not > > allowed to be used together, since --3way > > wrote conflict markers into the working tree. > > Hint that you are talking about the "git apply" command by > mentioning the name somewhere. > > Drop "previously"; we talk about the status quo in the present tense > in our proposed commit log messages to set the stage, and then describe > what the patch author percieves as a problem, before describing the > proposed solution to the problem. > > cf. Documentation/SubmittingPatches[[describe-changes]] (the whole section) > > > These changes change semantics so that if > > these flags are given together and there is > > a conflict, the conflicting objects are left > > at a higher order in the cache, and the command > > will return non-zero. If there is no conflict, > > the patch is applied directly to cache as > > expected and the command will return 0. > > Give an order to the codebase to "be like so". Here is my attempt. > > Teach "git apply" to accept "--cached" and "--3way" at the same > time. Only when all changes to all paths involved in the > application auto-resolve cleanly, the result is placed in the > index at stage #0 and the command exits with 0 status. If there > is any path whose conflict cannot be cleanly auto-resolved, the > original contents from common ancestor (stage #1), our version > (stage #2) and the contents from the patch (stage #3) for the > conflicted paths are left at separate stages without any attempt > to resolve the conflict at the content level, and the command > exists with non-zero status, because there is no place (like the > working tree files) to leave a half-resolved conflicted merge > result to ask the end-user to resolve. > > > The user can use `git diff` to view the contents > > of the conflict, or `git checkout -m -- .` to > > regenerate the conflict markers in the working > > directory. > > Nice. > > > With the combined --3way and --cached flags, > > The conflict markers won't be written to the > > working directory, so there is no point in > > attempting rerere. > > I am not sure what this paragraph is trying to convey here. > > I agree that when a *new* conflict is encountered in this new mode, > writing out a rerere pre-image, in preparation for accepting the > post-image the end-user gives us after the conflicts are resolved, > does not make sense, because we are not giving the end-user the > conflicted state and asking to help resolve it for us. > > But if a rerere database entry records a previous merge result in > which conflicts were resolved by the end user, it would make sense > to try reusing the resolution, I would think. I offhand do not know > how involved it would be to do so, so punting on that is fine, but > that is "there is no point", but it is "we are not trying". > > Perhaps > > When there are conflicts, theoretically, it would be nice to be > able to replay an existing entry in the rerere database that > records already resolved conflict that match the current one, > but that would be too much work, so let's not try it for now. > > would be a good explanation why we are not doing (i.e. we made a > trade-off) and recording that is important, as it will allow others > in the future to try building on the change we are proposing here > (it is not like we decided that it is fundamentally wrong to try to > use rerere in this situation). > > > Signed-off-by: Jerry Zhang <jerry@xxxxxxxxxx> > > Signed-off-by: Jerry Zhang <jerryxzha@xxxxxxxxxxxxxx> > > Unless we are interacting with two people with the same name, please > sign-off with the same name/address as the name/address that will be > recorded as the author of this change. I am guessing that dropping > the latter should be sufficient? > > Thanks.
