README.md: Set clean_git_config = false in sample config.toml.

[mrpippy]

By default, the GitLab runner "cleans" the git config before reusing an existing repo. This results in settings like core.ignorecase and core.precomposeunicode being removed; these are set automatically true for new repos on macOS, and disabling them can cause weird errors.

clean_git_config defaults to true when using the custom executor but is false when using the shell executor, this is why typical macOS CI setups using the shell executor don't need this option.

[edigaryev]

Hello Brendan 👋

According to:

• https://gitlab.com/gitlab-org/gitlab-runner/-/issues/38827
• https://gitlab.com/gitlab-org/gitlab-runner/-/merge_requests/5598

This should've been fixed in 18.1. Currently, the latest version available from Homebrew is 18.9.0.

1. Which GitLab Runner version are you using?

2. If you're already on the latest version, what are the steps to reproduce this?

[mrpippy]

Hi, I'm running v18.8.0. Our CI configuration is quite complex and I'm not sure how to easily reproduce it, but this is with GIT_STRATEGY = fetch. On the initial clone core.ignorecase and core.precomposeunicode are set in .git/config, but on the next job that reuses the tree, they've been removed.

In the builds dir, git-template/config also does not contain core.ignorecase or core.precomposeunicode. I don't know how the config cleaning is supposed to work, maybe the issue is that the template config doesn't contain those for some reason?

[edigaryev]

@mrpippy I think a proper place to address this issue is the GitLab Runner repository. See:

• https://gitlab.com/gitlab-org/gitlab-runner/-/work_items/38827
• https://gitlab.com/gitlab-org/gitlab-runner/-/merge_requests/5598

Simply setting the clean_git_config to false might not be suitable for some users.