Re: [PATCH 00/26] Moving global state into the repository object (part 1)

From: Stefan Beller <sbeller@google.com>
Date: Feb 13, 2018, 19:23 UTC
Message-ID: <CAGZ79kZOq+_NOOabBUtPJ_zKNb_vdais70F6VzVFoSn5B5A4fQ@mail.gmail.com>
In-Reply-To: <xmqq7ergra2y.fsf@gitster-ct.c.googlers.com>

On Tue, Feb 13, 2018 at 10:57 AM, Junio C Hamano <gitster@pobox.com> wrote:

Show 15 quoted lines

> Stefan Beller <sbeller@google.com> writes:
>
>> Oh, that is an interesting perspective. Here is how I arrived at the opposite
>> conclusion initially: Searching for 'ignore_env' shows that we care about it
>> as well for the index and graft paths, which are not the object store, hence
>> it would be better kept in the repository. (The alternative would be to
>> duplicate it into the raw object store, but I do not like data duplication)
>>
>> But maybe it is better to duplicate this one bit instead of passing through
>> a larger scoped object.
>
> If a larger scoped repository refers to a smaller scoped
> object-store, is there still a need to duplicate that bit, instead
> of referring to the bit the smaller scoped one has when asking about
> the bit in the larger scoped one?

No (in theory). But in practice it may be worthwhile:

    "What's the value of this ref?"

    "Oh let me check the ignore_env bit that happens
    to live in the object store first."

would be super confusing to me.

Show 6 quoted lines

> I am not sure if these "do not look at environment variables" is an
> attribute of these entities---it sounds more like an attribute for
> each invocation of an operation, i.e. "I want to learn where the
> index is but would ignore GIT_INDEX environment for this particular
> query." and "What's the value of this ref?  Please honor the
> common-dir environment during this query".

That sounds like we want to have a configset struct eventually.

For now the ignore_env bit lives in the repository, as that helps when working with submodules, when reading its comments. Unfortunately 359efeffc1 (repository: introduce the repository object, 2017-06-22) did not reason about the existence of the ignore_env flag in its commit message.

> So from that point of view, it may not matter where the "bit" lives,
> among repository, object-store, or ref-store.

It matters on the scale of confusing the developer?

Stefan