Re: [Outreachy PATCH v2] environment: move "core.attributesFile" into repo-setting

From: Junio C Hamano <gitster@pobox.com>
Date: Jan 5, 2026, 22:24 UTC
Message-ID: <xmqq1pk3lmu3.fsf@gitster.g>
In-Reply-To: <a881499d-e236-4f8e-a217-b6bce69e3e3c@gmail.com>

Phillip Wood <phillip.wood123@gmail.com> writes:

> If I run 'git -c core.attributesFile=~does-not-exist rebase -i' with git 
> built from master it fails immediately with "fatal: failed to expand 
> user dir in: '~does-not-exist'".

Hmph, if you call any behaviour change a "regression", this may certainly count as one, but I do not necessarily think the above is a good behaviour.

Think about a use case where attributes are not used at all, e.g., "git -c core.attributesFile=~does-not-matter cat-file -t HEAD"; would it make sense to barf when your configuration file has an invalid definition for what you are *not* using? So if the change makes it stop barfing, it can even be argued that this is an improvement.

> It is quite common that moving from parsing config settings eagerly by 
> calling repo_config() at startup to parsing them lazily via 'stuct 
> repo_settings' causes regressions like this. We really should find a way 
> to address that before moving more settings into 'struct repo_settings'

Very true. If we know the set of things we parse early and have a way to say "this command only X, Y, and Z matters (but not W)", then the above cat-file example can omit the attributesFile from the "we care" set.

I think overusing repo_settings is a disease. Moving a singleton global to per repository (by adding to struct repository) is one thing and it is very welcome. But changing the way configuration variables are parsed (e.g., what used to be parsed by only those who care about is now parsed by everybody, or vice versa) needs to be handled carefully.