Fish Shell abbreviations–what are they and how to configure them?

Fish Shell abbreviations are a fantastic way to configure what is commonly known as aliases for your day-to-day use.

The difference between an alias and an abbreviation is that it expands to the entire command whenever the abbreviation gets triggered. Traditionally, aliases are shown as they are typed in the shell’s history.

The expansion is an excellent benefit of using abbreviations. One can always see the actual command behind the shorthand version. This is both useful for remembering the actual command and significant when sharing commands with others (such as in screenshots of the terminal), as they do not have to decode the aliases.

Let’s configure some abbreviations

We will edit the ~/.config/fish/conf.d/abbreviations.fish file. Any file in the ~/.config/fish/conf.d directory will be automatically loaded in a standard fish setup. A separate file for abbreviations makes it easier to find the right place to configure them.

Below is the content of my file:

abbr be "bundle exec"

abbr ghb "gh browse" # Open the current repository on GitHub
abbr ghc "hub compare" # Open the diff of the branch on GitHub

abbr bu "brew upgrade"

As you can see, the syntax is similar to the alias. We use the abbr command, followed by the abbreviation we’d like to use. Finally, the actual command it should expand to.

To use the configured abbreviation, we need to type it, and either press Enter to expand and execute, or Space to only expand it, allowing us to add any arguments to the command.

Here’s a demo:

Abbreviations add another touch of clarity to your own workflow. Switching from using aliases is trivial. To me, they are superior and a clear improvement.

Bonus points

I’ve found fish-git-abbr plugin to be a fantastic collection of predefined abbreviations for git usage. It’s got everything you might need when working with git and save some keystrokes. I have also learned some new git arguments!

Last modified: 06-Feb-24