Adding Git Completion to Zsh

I recently switched my shell from Bash to Zsh, and after installing my new favorite extensions (Powerlevel10k and Meslo Nerd Font), I realized I was missing a key component from Bash: Git completion.

Since we don’t all have the luxury of running `brew install bash-completion` and following the associated directions, I’ll discuss how I manually installed the shell scripts necessary to support Git completion in Zsh.

Finding the Dependencies

The Git community maintains all the shell completion scripts in their repository on GitHub. Navigating to this folder reveals scripts for a variety of shells, including Bash and Zsh.

Since both Bash and Zsh are based on the Bourne shell, they tend to share many similarities. Git makes this pretty evident after one opens the `git-completion.zsh` and the comment at the top states:

You need git’s bash completion script installed somewhere, by default it would be the location bash-completion uses.

Thus, we need two scripts to have Git completion in its entirety.

Downloading the Scripts

Now that it is clear which scripts are necessary for full Git completion functionality, let’s get them:

Notice how, by convention, I placed the shell scripts in a folder called `.zsh` under the user’s home folder.

Configuring the Shell

Once the scripts are in position, the `.zshrc` file may be configured to provide access to their functionality. Open up the `~/.zshrc` file and add the following lines of code:

On your first run, make sure you clear out the shell’s autocompletion cache with:

Then save the script, reload your shell, and voila!

For the curious reader, here’s a quick summary of what the above configuration script accomplishes:

• `zstyle`: Instructs the shell on how to provide inline, contextual hints
• `fpath`: The `git-completion.zsh` is a function file, not designed to be sourced like the bash script. This command appends the `~/.zsh` directory onto the shell’s function lookup list.
• `autoload`: Scan each path within the `fpath` variable for files starting with an underscore (`_git,` in our case) and loads the corresponding script as a function file
• `compinit`: Initializes the shell’s auto-completion functionality

References

These links proved themselves immensely helpful as I learned how to understand and configure this on my own:

• Git Completion Script in Zsh
• Zsh Completion System
• Zsh Styling
• Zsh Functions
• Using compinit