Are multiple `.gitignore`s frowned on?

Question

Unless a repo consisted of several independent projects, it seems it would be simplest to just have one .gitignore file at the root of the repo than various ones throughout. Is there a standard best practice on this or some analysis online of when one approach is better than the other?

Answer 1

You can have multiple .gitignore, as long as they are in different directory.

And you can have different version of a .gitignore file per branch: I have already seen that kind of configuration for ensuring one branch ignores a file while the other branch does not: see this question for instance.

If your repo includes several independent projects, it would be best to reference them as submodules though.
That would be the actual best practices, allowing each of those projects to be cloned independently (with their respective .gitignore files), while being referenced by a specific revision in a global parent project.
See true nature of submodules for more.

Answer 2

I can think of at least two situations where you would want to have multiple .gitignore files in different (sub)directories.

• Different directories have different types of file to ignore. For example the .gitignore in the top directory of your project ignores generated programs, while Documentation/.gitignore ignores generated documentation.

• Ignore given files only in given (sub)directory (you can use /sub/foo in .gitignore, though).

Please remember that patterns in .gitignore file apply recursively to the (sub)directory the file is in and all its subdirectories, unless pattern contains '/' (so e.g. pattern name applies to any file named name in given directory and all its subdirectories, while /name appliest to file with this name only in given directory).

Answer 3

As a tangential note, one case where the ability to have multiple .gitignore files is very useful is if you want an extra directory in your working copy that you never intend to commit. Just put a 1-byte .gitignore (containing just a single asterisk) in that directory and it will never show up in git status etc.