On Thu, May 9, 2013 at 12:15 PM, Junio C Hamano <gits...@pobox.com> wrote: > John Keeping <j...@keeping.me.uk> writes: > >> On Thu, May 09, 2013 at 09:10:51AM -0700, Junio C Hamano wrote: >>> David Aguilar <dav...@gmail.com> writes: >>> >>> > Marked "RFC" because I am kinda against adding more configuration >>> > variables. >>> >>> Just like "git merge" has -X<option> escape hatch to allow us to >>> pass backend-specific options, perhaps you can add a mechanism to >>> "git mergetool" to let the user pass --no-auto from the command >>> line? >> >> We already have "mergetool.<tool>.cmd" which allows a completely custom >> command line to be specified. > > Then probably it is a good idea to drop this patch and replace it > with a documentation patch to suggest those who do not want --auto > to use that mechanism?
Generally, "mergetool.<tool>.cmd" is not general enough since we've always special cased the base vs. no-base code paths and we run different commands depending on whether a base is available. It might make sense to extend that mechanism to allow "mergetool.<tool>.merge2cmd" for the no-base form and allow .cmd to remain as-is for the full 3-arg base form, but IMO that's an even worse solution for the end user as they now need to configure two separate variables and know all the intimate details about how to configure it. OTOH, a boolean git configuration flag is much easier and simpler for the user. The -X--no-auto idea could work, but I was hoping for a "set once and forget" fix I could hand to a user, which would remove the need for such a feature. Here's the background behind why I wrote this patch -- yesterday someone at work asked, "does git mergetool not work with stash?" This caught me by surprise, "yes, of course it does", I replied, but they showed me a case where the behavior was confusing. They had done "git stash && git pull --rebase && git stash pop". That last pop created a merge conflict in one file. They then ran "git mergetool" to resolve the merge but they never saw the GUI and their changes were automatically staged. From a user's POV this is unintuitive and confusing behavior because they were expecting to run kdiff3, but instead it silently staged the file with kdiff3's auto-merged result. We could drop --auto altogether, which maybe is a better course of action since it makes the behavior predictable and un-surprising, but I do not know if anyone has come to rely on kdiff3's "auto-merge" feature (hence the extended Cc: list). Because I do not know exactly why "kdiff3" thinks these are "trivial merges" it can resolve while "git stash pop" disagrees and cannot trivially merge them, I seems that dropping "--auto" really may be the better choice all around. In general, git tries to be extremely careful and defers to the user in the face of ambiguity. Dropping --auto would make sense from that POV since kdiff3 is preventing the user from inspecting the result. In other words, if there are no strong reasons to keep --auto then I would not be opposed to changing the default. OTOH if there are users that want it and some that don't, then the config variable is helpful, and maybe it can be flipped the other way: call it "mergetool.kdiff3.autoMerge", keep it False today, and maybe change the default to True with Git 2.0. But I would really prefer no configuration and the most intuitive and least-surprising behavior. I think I've convinced myself that dropping --auto altogether could accomplish this, but I do not want to pull the rug out from under existing users, *if they exist*. If everyone in this discussion is in the camp of, "I didn't even know it worked that way" then changing the behavior is not so big a deal and we can do without extra variables. Would it be acceptable for me to rework this patch to drop --auto altogether? -- David -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
