Don't create .gitkeep files, use .gitignore instead

Source: Hacker News

2023-09-18

Git only tracks files, not directories. It will only create a directory if it contains a tracked file. But sometimes you need to “track” a directory, to ensure it exists for fresh clones of a repository. For example, you might need an output directory called build.

In this post, we’ll look at two ways to achieve this. First, the common but slightly flawed .gitkeep technique, then a simpler one using only a .gitignore file.

The .gitkeep technique

This technique uses an empty file called .gitkeep:

build
└── .gitkeep

The empty file ensures that Git creates the directory with minimal cost. Any other filename may be used, as Git doesn’t treat .gitkeep files any differently.

To set this up, you might create an empty file with touch:

$ touch build/.gitkeep

Then ignore all files in the directory, except .gitkeep, by adding patterns in the repository’s .gitignore file:

/build/*
!/build/.gitkeep

The first pattern ignores everything in the build directory. The second one then un‑ignores the .gitkeep file, allowing it to be committed.

Downsides

• It requires editing two files.
• If the directory is renamed, .gitignore needs updating, which is easy to miss.
• .gitkeep is not a name recognized by Git, so there’s no documentation on it, potentially confusing other developers.

The better .gitignore technique

This technique uses only a short .gitignore file inside the directory:

build
└── .gitignore

The .gitignore file has these contents:

*
!.gitignore

The first pattern ignores all files in the directory. The second one then un‑ignores the .gitignore file, so it can be committed.

You can create this file with echo and file redirection:

$ echo '*\n!.gitignore' > build/.gitignore

When you add and commit the directory, Git will pick up the .gitignore file first, skipping other files within the directory:

$ git add build

$ git status
On branch main
Changes to be committed:
        new file:   build/.gitignore

$ git commit -m "Track build directory"
[main 1cc9120] Track build directory
 1 file changed, 2 insertions(+)
 create mode 100644 build/.gitignore

The directory is now “tracked” with a single, standard file that will work even after renames.

Conclusion

Don’t ignore this technique.