Re: [PATCH v2 4/5] setup: make object format configurable via config

From: Junio C Hamano <gitster@pobox.com>
Date: Aug 16, 2024, 17:13 UTC
Message-ID: <xmqqed6ol7bw.fsf@gitster.g>
In-Reply-To: <85086620628b1fa136ebf7a1c9e2f64ebdbc7b92.1723798388.git.ps@pks.im>

Patrick Steinhardt <ps@pks.im> writes:

Show 11 quoted lines

> The precedence order now is the following, where the first one wins:
>
>   1. The `--object-format=` switch.
>
>   2. The `GIT_DEFAULT_HASH` environment variable.
>
>   3. The `init.defaultObjectFormat` config variable.
>
> This matches the typical precedence order we use in Git. We typically
> let the environment override the config such that the latter can easily
> be overridden on an ephemeral basis, for example by scripts.

Thanks for documenting this, as the reason for deciding the precedence between environment and configuration is no longer as strong as it used to be.

Before the "git -c var=val" happened, the only sensible preference order was to allow environment to override a configured default by doing "VAR=val git cmd ...". In other words, the order used to be something you could safely forget and still infer the right order with logic alone.

But with "git -c var=val", even if a hypothetical Git allowed configuration to override environment, a user could still override them with "-c var=val", so "environment trumps configuration" is no longer "because there is no sensible workaround if it were the other way around", but merely "because that used to be the only logical way".