Re: Bugreport - submodules are fetched twice in some cases

From: Glen Choo <chooglen@google.com>
Date: Apr 29, 2022, 19:05 UTC
Message-ID: <kl6l4k2bpv61.fsf@chooglen-macbookpro.roam.corp.google.com>
In-Reply-To: <xmqqczgzdc1r.fsf@gitster.g>

Junio C Hamano <gitster@pobox.com> writes:

Show 32 quoted lines

> A simple and concrete reproduction 
>
>     git init top
>     cd top
>     date >file1
>     git init sub
>     cd sub
>     date >subfile1
>     git add .
>     git commit -m subinitial
>     cd .. ;# back to top
>     git submodule add ./sub sub
>     git add file1
>     git commit -m initial
>     cd .. ;# out of top
>     git clone --recurse-submodules top copy
>     cd copy
>     git config submodule.recurse true
>     git config fetch.parallel 0
>     GIT_TRACE2=$(pwd)/trace git fetch --all --prune --prune-tags
>
> This throws the three lines to the output.
>
> Fetching origin
> Fetching submodule sub
> Fetching submodule sub
>
> The two "Fetching submodule" messages are coming from two separate
> calls to get_fetch_task_from_index(), and the trace does show that
> the code is doing "git-upload-pack" three times (one for the top
> level, twice for the same top/sub).  We can see it by grepping
> for "git-upload-pack" in the resulting 'trace' file above.

 
Thanks for the reproduction recipe and findings, that'll be very helpful
:)

> Glen, as submodule.c::fetch_submodules() was created in your heavy
> refactoring quite recently, I thought I'd redirect this report in
> your direction, as I expect you'd be the most clueful in this area
> ;-)

Hm, this does look like something that I probably introduced. But even if it turns out to be older than that, I think I am the right person to fix it, yes.

I'm a little caught up with the embedded bare repo work, but I think I can find time to debug this within the next 2 working days or so.