Re: [RFC 00/10] Make .the gitmodules file path configurable

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Apr 23, 2018, 17:47 UTC
Message-ID: <20180423174709.GA25128@aiede.svl.corp.google.com>
In-Reply-To: <20180412222047.5716-1-ao2@ao2.it>

Hi,

Antonio Ospite wrote:

> vcsh[1] uses bare git repositories and detached work-trees to manage
> *distinct* sets of configuration files directly into $HOME.

Cool! I like the tooling you're creating for this, though keep in mind that Git has some weaknesses as a tool for deployment.

In particular, keep in mind that when git updates a file, there is a period of time while it is missing from the filesystem, which can be problematic for dotfiles.

[...]

Show 9 quoted lines

> However when multiple repositories take turns using the same directory
> as their work-tree, and more than one of them want to use submodules,
> there could still be conflicts about the '.gitmodules' file because git
> hardcodes this path.
>
> For comparison, in case of '.gitignore' a similar conflict might arise,
> but git has alternative ways to specify exclude files, so vcsh solves
> this by setting core.excludesFile for each repository and track ignored
> files somewhere else (in ~/.gitignore.d/$VCSH_REPO_NAME).

For reference:

	core.excludesFile
		Specifies the pathname to the file that contains
		patterns to describe paths that are not meant to be
		tracked, in addition to .gitignore (per-directory) and
		.git/info/exclude. Defaults to
		$XDG_CONFIG_HOME/git/ignore. If $XDG_CONFIG_HOME is
		either not set or empty, $HOME/.config/git/ignore is
		used instead. See gitignore(5).

Using this as a substitute for <worktree>/.gitignore is a bit of a hack. It happens to work, though, so reading on. :)

[...]

> So this series proposes a mechanism to set an alternative path for the
> submodules configuration file (from now on "gitmodules file").

I am nervous about this. I wonder if there is another way to accomplish the goal.

One possibility would be to handle the case where .gitmodules is excluded by a sparse checkout specification and use .gitmodules from the index in that case. Would that work for you?

Thanks, Jonathan