Three ways to ignore files in Git

This post may contain outdated information

I initially wrote this post a while ago and some of its content might be outdated.

TIL I learned that there are different ways to ignore files in Git:

1. Using a .gitignore file in a repository

When created in a Git repository, this .gitignore is only applied to the directory it is in and its children. This means that you can ignore files in the whole repository and also ignore some files in some subdirectories.

Start by creating a .gitignore in a subdirectory:

# lib/.gitignore
*.md

With the following directory structure:

.
├── lib
│   ├── .gitignore
│   ├── todo.md        # <- Will be ignored
└── Readme.md          # <- Will not be ignored

This file should be version-controlled and includes files that all developers working on the repository will want to ignore.

2. Using the local exclusion file .git/info/exclude

Start by creating the info directory and the exclude file in our repository .git directory:

mkdir -p .git/info
touch exclude

Then you can add files or pattern of files you want to ignore:

TODO.md
NOTES.txt

I mainly use it to ignore files that do not need to be shared with other developers. I usually leave notes a list of TODOs at the root of a project and ignore them in this file.

3. Using a global .gitignore

Start by making a .gitignore file in your home directory, with the files you want to ignore, and place in your home directory:

# ~/.gitignore

.vimrc.local
*.swp

.idea
.DS_Store

Then, tell Git to use this file as global .gitignore by running in your shell:

git config --global core.excludesfile ~/.gitignore

I use it to ignore file I never want to be committed, e.g. backup or temporary files, build artifacts, etc.

Further reading