'commitPrefixes' config triggers 'deprecated config' warning

[abidkyo]

Describe the bug

I got this warning when commitPrefixes is defined in the config.

Provided user config is deprecated but auto-fixable. Attempting to write fixed version back to file...
Success. New config written to /home/abidkyo/.config/lazygit/config.yml

The 'fixed' config contains just whitespace changes,
which the indentation is 4-spaces instead of 2-spaces.

I believe the bug is from #4261

To Reproduce

1. Add the commitPrefixes config as described in
   https://github.com/jesseduffield/lazygit/blob/master/docs/Config.md#predefined-commit-message-prefix
2. launch lazygit
3. see the 'whitespace' changes in the config file
4. quit lazygit and see the warning in the command-line

Expected behavior

• no change of config file
• if change is necessary, use 2-spaces indentation

Version info:
commit=101bbb0ac56a1cf594301f45bda22c551f1aa870, build date=2025-02-22T11:33:02Z, build source=binaryRelease, version=0.47.1, os=linux, arch=amd64, git version=2.43.0

[ChrisMcD1]

The 2 spaces indentation change is one that I believe is unavoidable (without more substantial changes), and would happen with any other of the automatic config rewriting systems. It is just doing a yaml.Marshall upon making any changes, and has no knowledge of what the users preferred yaml indentation style is.

But I can fix the code so that this does not trigger a rewrite at all!

[stefanhaller]

The 2 spaces indentation change is one that I believe is unavoidable (without more substantial changes), and would happen with any other of the automatic config rewriting systems. It is just doing a yaml.Marshall upon making any changes, and has no knowledge of what the users preferred yaml indentation style is.

While that's correct, we can still mitigate this a little bit by using an indentation of 2 when rewriting the file. I think this is a saner value to use, and is probably what most people use. See #4312.

[stefanhaller]

Fixed by #4311