Re: [PATCH v2] [GSoC] submodule--helper: introduce add-clone subcommand

[Atharva Raykar <raykar.ath@gmail.com>]

On 04-Jun-2021, at 17:07, Shourya Shukla <shouryashukla.oo@gmail.com> wrote:
> 
> Hi Atharva!
> 
> On Wed, Jun 2, 2021 at 6:43 PM Atharva Raykar <raykar.ath@gmail.com> wrote:
>> 
>> Let's add a new "add-clone" subcommand to `git submodule--helper` with
>> the goal of converting part of the shell code in git-submodule.sh
>> related to `git submodule add` into C code. This new subcommand clones
>> the repository that is to be added, and checks out to the appropriate
>> branch.
>> 
>> This is meant to be a faithful conversion that leaves the behaviour of
>> 'submodule add' unchanged. The only minor change is that if a submodule name has
>> been supplied with a name that clashes with a local submodule, the message shown
>> to the user ("A git directory for 'foo' is found locally...") is prepended with
>> "error" for clarity.
> 
> It would be better if commit messages are limited to 72 columns
> (characters) per line.
> Though you can obviously write longer lines on the list no problem.

Good catch. My auto-fill settings had got switched to length 80.
I'll be careful next time.

>> This is part of a series of changes that will result in all of 'submodule add'
>> being converted to C.
>> 
>> Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
>> Mentored-by: Christian Couder <christian.couder@gmail.com>
>> Mentored-by: Shourya Shukla <shouryashukla.oo@gmail.com>
>> Based-on-patch-by: Shourya Shukla <shouryashukla.oo@gmail.com>
>> Based-on-patch-by: Prathamesh Chavan <pc44800@gmail.com>
> 
> 
> I and others before me used to sign off the previous authors using
> 'Signed-off-by:'. This trailer
> has not been used yet so I am not sure if it should be used though I
> prefer this over the former.
> Maybe Christian could comment here?

Yeah, I wasn't sure if I should include an S.o.B without explicit
acknowledgement from you and Prathamesh.

>> This is part of a series of changes that will result in all of 'submodule add'
>> being converted to C, which is a more familiar language for Git developers, and
>> paves the way to improve performance and portability.
>> 
>> I have made this patch based on Shourya's patch[1]. I have decided to send the
>> changes in smaller, more reviewable parts. The add-clone subcommand of
>> submodule--helper is an intermediate change, while I work on translating all of
>> the code.
>> 
>> Another subcommand called 'add-config' will also be added in a separate patch
>> that handles the configuration on adding the module.
>> 
>> After those two changes look good enough, I will be converting whatever is left
>> of 'git submodule add' in the git-submodule.sh past the flag parsing into C code
>> by having one helper subcommand called 'git submodule--helper add' that will
>> incorporate the functionality of the other two helpers, as well. In that patch,
>> the 'add-clone' and 'add-config' subcommands will be removed from the commands
>> array, as they will be called from within the C code itself.
> 
> Seems like a good approach! BTW, if this "extra" message is a bit long
> like the one above, then
> you can put it in a cover letter instead. If people really want to
> read this extra information
> they will read it in a cover letter as well.
> 
> Just supply the '--cover-letter' option when executing the 'git
> format-patch' command.

Not too familiar with the convention here on how long a description
warrants a cover letter. Generally in the mailing list I found
[PATCH 0/1] labels far more uncommon than [PATCH] for single patch
changes, so I went with the common case.

>> Changes since v1:
>> * Fixed typos, and made commit message more explicit
>> * Fixed incorrect usage string
>> * Some style changes were made
> 
> To save yourself the trouble of sieving the "top" or "noteworthy" changes from
> the new version, you could instead just print the 'range-diff' between
> the two versions.
> 
> You can do:
> 'git range-diff b1~n1..b1 b2~n2..b2'
> 
> Where:
> 
> - 'b1' is the first branch; 'n1' is the number of top commits you are
> taking from 'b1' for
>  comparison.
> 
> - 'b2' is the second branch; 'n2' is the number of top commits you are
> taking from 'b2' for
>  comparison.
> 
> It will print a very detailed output showing what differences were
> there commit-wise
> amongst the two branches. This can be put at the end of the cover
> letter. Though, this
> isn't necessary if your way seems better to you.

Thanks for the tip. I felt since this change was mostly about code
style and naming, a range diff for it felt a little extra.

I liked it more when you used it in a previous v2 of your patch,
where the changes were more significant.

> BTW, it would be helpful if you could send mails addressed to me on my
> other email <periperidip@gmail.com>.

Got it.