Re: [PATCH 2/2] fetch, push: keep separate lists of submodules and gitlinks

From: Stefan Beller <sbeller@google.com>
Date: Oct 23, 2017, 18:05 UTC
Message-ID: <CAGZ79kYcvcEe2-K94BSB0j3ig-fgr9xvTg5q4H6vak1H6LkE+Q@mail.gmail.com>
In-Reply-To: <20171023141259.GB85043@book.hvoigt.net>

On Mon, Oct 23, 2017 at 7:12 AM, Heiko Voigt <hvoigt@hvoigt.net> wrote:

Show 29 quoted lines

> On Thu, Oct 19, 2017 at 11:11:09AM -0700, Stefan Beller wrote:
>> Currently when fetching we collect the names of submodules to be fetched
>> in a list. As we also want to support fetching 'gitlinks, that happen to
>> have a repo checked out at the right place', we'll just pretend that these
>> are submodules. We do that by assuming their path is their name. This in
>> turn can yield collisions between the name-namespace and the
>> path-namespace. (See the previous test for a demonstration.)
>>
>> This patch rewrites the code such that we treat the 'real submodule' case
>> differently from the 'gitlink, but ok' case. This introduces a bit
>> of code duplication, but gets rid of the confusing mapping between names
>> and paths.
>>
>> The test is incomplete as the long term vision is not achieved yet.
>> (which would be fetching both the renamed submodule as well as
>> the gitlink thing, putting them in place via e.g. git-pull)
>>
>> Signed-off-by: Stefan Beller <sbeller@google.com>
>> ---
>>
>>  Heiko,
>>  Junio,
>>
>>  I assumed the code would ease up a lot more, but now I am undecided if
>>  I want to keep arguing as the code is not stopping to be ugly. :)
>
> So we are basically coming to the same conclusion? :) My previous
> fallback approach basically did the same but with the old architecture
> (without parallel fetch, ...) and was already ugly.

It depends on the conclusion you drew. ;)
Here is my conclusion:
* It would really be nice to have this fallback separated out.
* However for the current state the ugliness of such code trumps the
  more maintainable, long term oriented thing with path/names not
  clashing. I could not spend more time polishing these patches,
  so I could not ask you to do it either
-> I think your patches are fine as is for inclusion
-> We may have #leftoverbits here to clear up the confusion around
  path/names, as well as making the code more pleasant to read.

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> With the fallback on submodule default names approach we can keep most
> of the old functionality and keep the code that handles that minimal.
>
> Since there is only a small (IMO quite unlikely) cornercase that could
> break peoples expectations I would like to have a look whether anyone
> even notices the behavioral change on next or master. If there are
> complaints we can still extend and add the two lists.

That sounds good to me.

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>
>>  The idea is to treat submodule and gitlinks separately, with submodules
>>  supporting renames, and gitlinks as a historic artefact.
>>
>>  Sorry for the noise about code ugliness.
>
> Why sorry? For me it is actually interesting to see you basically coming
> to the same conclusions.

I thought I might come off awkwardly criticizing code for ugliness without having a better alternative to show.

Thanks for working on this, Stefan

>
> Cheers Heiko