Hi Phillippe and Junio, On Tue, Aug 10, 2021 at 4:04 PM Philippe Blain <levraiphilippeblain@xxxxxxxxx> wrote: > > Hi Junio, > > Le 2021-08-10 à 14:36, Junio C Hamano a écrit : > > Mahi Kolla <mahikolla@xxxxxxxxxx> writes: > > > >>> Is it possible to avoid changing the behaviour unconditionally and > >>> potentially breaking existing users by making it an opt-in feature, > >>> e.g. "git clone --recurse-submodules" would work as the current > >>> users would expect, while "git clone --recurse-submodules=sticky" > >>> would set submodule.recurse to true, or something? > >> > >> As mentioned, the `submodule.recurse=true` will only apply to active > >> submodules specified by the user. Setting this config value when the > >> user runs their initial `git clone` minimizes the number of times a > >> developer must use the `--recurse-submodule` option on other commands. > >> > >> However, this is a behavior change that may be surprising for > >> developers. To ensure a smooth rollout and easy adoption, I think > >> adding a message using an `advice.*` config setting would be useful. > > > > It may be better than nothing, but that still is a unilateral > > behaviour change. Can't we come up with a way to make it an opt-in > > feature? I've already suggested to allow the "--recurse-submodules" > > option of "git clone" to take an optional parameter (e.g. "sticky") > > so that the user can request configuration variable to be set, but > > you seem to be ignoring or skirting it. > > The '--recures-submodule' option in 'git clone' already takes an optional > argument, which is a pathspec and if given, only submodules matching the given > pathspec will be initialized (as opposed to all submodules if the flag is given without > an argument). So, it does not seem to be possible to use this > flag as a way to also set 'submodule.recurse'. > Because of the optional pathspec argument, adding a `=sticky` argument to the option may be hard to implement. That was my initial hesitation to the opt in design. > When Emily (CC'ed) sent her roadmap for submodule enhancements in [1], the enhancement > that Mahi is suggesting was explicitely mentioned: > > > - git clone > ... > > What doesn't already work: > > > > * --recurse-submodules should turn on submodule.recurse=true > > I don't know if Mahi is part of this effort or just came up with the same idea, > but in any case maybe Emily would be able to add more justification for this change. > I am part of the team and am implementing that exact feature from the roadmap :) > > Even though I am not > > married to the "give optional parameter to --recurse-submodules" > > design, unconditionally setting the variable, with or without advice > > or warning, is a regression we'd want to avoid. > > > > In my opinion, it would not be a regression; it would a behaviour change that > would be a *vast improvement* for the majority of projects that use submodules, at > least those that use non-optional submodules (which, I believe, is the vast majority > of projects that use submodules, judging by what I've read on the web over the past 3 > years of my interest in the subject.) > > As soon as you use submodules in a non-optional way, you really *want* submodule.recurse=true, > because if not: > > 1. 'git checkout' does not recursively check out your submodules, which probably breaks your build. > You have to remember to always run 'git checkout --recurse-submodules' or run 'git submdule update' > after each checkout, and teach your team to do the same. > 2. 'git pull' fetches submodules commits, but does not recursively check out your submodules, > which also probably breaks your build. You have to remember to always run 'git pull --recurse-submodules', > or run 'git submodule update' after each pull, and also teach your team to do so. > 3. If you forget to do 1. or 2., and then use 'git commit -am "some message" (as a lot > of Git beginners unfortunately do), you regress the submodule commit, creating a lot > of problems down the line. > > These are the main reasons that I think Git should recurse by default. Setting 'submodule.recurse' > also brings other niceties, like 'git grep' recursing into submodules. > I completely agree with this! These are a lot of the reasons why the feature was initially suggested. An alternative path forward the team discussed was testing `submodule.recurse=true` under `feature.experimental`. This way we can collect feedback from developers before making this the default config value. > If we can agree that the behaviour *should* change eventually, then at least > 'git clone --recurse-submodules' could be changed *right now* to suggest setting > 'submodule.recurse' using the advice API, and stating that this will be the default > some day. > > Even if we don't agree that the behaviour should enventually change, I think > having this advice would be a strict improvement because > it would help user discover the setting, which would already go a long way. > > Thanks, > > Philippe. > > > [1] https://lore.kernel.org/git/YHofmWcIAidkvJiD@xxxxxxxxxx/ I agree that adding an advice message when a user runs `git clone --recurse-submodules` would at least alert users of their options, giving them the choice to set `submodule.recurse` accordingly. Thanks! Best, Mahi Kolla
