Keep unwanted files out of your repo for good with global .gitignore

TLDR: git config --global core.excludesFile '~/.gitignore'

Ever raised a PR and found a surprise .DS_Store or perhaps even tired of seeing the .idea folder rear its ugly head in your repo. Well fret no more! Similar to its functionality in a repository, the .gitignore file can be used to exclude (or explicitly include) files in a project. In this case, we will be setting it up to exclude files across all repos.

It is good practice not to throw a bunch of random file names into your repository's .gitignore so separating out these user files is a good way to keep your repositories a little cleaner.

Here's an example of what a .gitignore for a project might be.

# Logs  
logs  
*.log  
npm-debug.log*  
yarn-debug.log*  
yarn-error.log*  
pnpm-debug.log*  
lerna-debug.log*  

# Package management
.yarn/*  
!.yarn/cache  # this is how you whitelist a specific items
!.yarn/patches  
!.yarn/plugins  
!.yarn/releases  
!.yarn/sdks  
!.yarn/versions

# Editor directories and files  
.vscode/*  
!.vscode/extensions.json  
.idea  
.DS_Store

Can you see an an issue with this project .gitignore file? We're including several files that are related to the editor you use or the operating system you're on, no bueno! If it's not relevant to all people picking up and running the project, it probably shouldn't be in there.

Create the global gitignore

Let's solve this problem by setting up a global .gitignore. This file can be located anywhere but common practice is to put it at the at the root of your user. If you choose to put it elsewhere put it somewhere it's not going to get lost.

Create a file in ~/.gitignore and add anything you want to exclude from all your repositories in there. Put only what you need in there, you can always add more later.

# `~/.gitignore`

# VSCode exclude files and root level directories
.vscode/*

# VSCode - but keep project specific extensions
!.vscode/extensions.json

# Intellij IDE project options
.idea

# Mac OSX folder information
.DS_Store

If you want to understand what each of the options do in full check out (pun intended) this cheatsheet

note: .gitignore comments have to start at the beginning of a line

Adding the file to your git config

Once you're done setting up your file run the command

git config --global core.excludesFile '~/.gitignore'

This command will add the file to your globally ignored directories. Voila! You're done.

Awesome-saucesome! But...

but what if I want to commit my excluded config for a single repository

The easiest way to achieve this is by explicitly adding them back, whitelisting the items you want. If you specifically need a file for a project, that would give it the justification to keep it in the repo. You can re-add it back in with !<file/folder name>.

...

!.DS_Store # (not sure why you'd need the .DS_Store but you do you)

Now your excluded files can be tracked by git.

That is how you set up a global .gitignore.