How to Create a ZSH Find and Preview Command Line Widget

Like most devs, I like living in the terminal for quick operations (git-ops, quick-edits, moving files around, etc.).

Some of my most used CLI tools, in no particular order, are:

• git - The most widely used SCM tool, "not owned" in any way by GitHub.

• Zsh - The Z Shell, with starship prompt.

• fzf - One of the most popular command-line fuzzy finders.

• Unix Commands - like alias, cat, grep, and more like these.

... and many more tools and utilities, preserved in my dotfiles.

Today, I want to show you how you can create a quick find and edit widget like the one shown below:

Widget with a preview window on the side:

Widget with a preview window on the bottom

As a bonus, you can trigger the widget with Ctrl+P shortcut keys similar to text editors like vs-code.

OK — here is how you can get this:

Firstly, we assume you are on Zsh; if not, these widgets will not work with the code I shared below. So, with that clarified, let's move to the setup.

Install these pre-requisites:

1. fzf - Command-line fuzzy finder: github.com/junegunn/fzf

2. fd - Very fast alternative to find command: github.com/sharkdp/fd

Next, you want to add the below in a location you can source with your zsh configuration. I typically create a ~/.bin/functions.sh, which I source in my ~/.zshrc.

Here is the complete snippet, which I will break down in a bit:

Once you have set it up correctly, you can press Ctrl+P or Ctrl+O in a directory of your choice to start looking up the file you want, which will open in the vi editor.

Here the exciting bits are:

• Making fd traverse the directory structure, ignoring things like .git.

    fd --type f  --hidden --follow --exclude .git
  

• Creating a couple of functions with custom fzf styling and configuration. For example, for a layout that opens below your input cursor, we can do the below:

    fzf --height 80% \
        --layout reverse \
        --info inline \
        --border \
        --preview "bat --style=numbers --color=always {} | head -500" \
        --preview-window "down:24:noborder" \
        --color=dark \
        --color=fg:-1,bg:-1,hl:#5fff87,fg+:-1,bg+:-1,hl+:#ffaf5f \
        --color=info:#af87ff,prompt:#5fff87,pointer:#ff87d7,marker:#ff87d7,spinner:#ff87d7 \
        --prompt="File > "
  

  

  You should check out the official fzf repository for more examples and documentation.

• The next bit is capturing the selection from fzf in a buffer, which we do with: --query "$LBUFFER" as seen in the code.

• And then, the below bits drive it home by asking Zsh to execute the string in the buffer like so:

    if [ -n "$selected_file" ]; then
        BUFFER="vi $selected_file"
        zle accept-line
    fi
    zle reset-prompt
  

  Here zle, short for "Zsh line editor," is a built-in utility for Zsh that we leverage to accept the input and reset if the user changes the mind.

• One thing to note in the code is the BUFFER="vi $selected_file" bit passes the selected file to vi editor — our editor of choice. You can swap that for code, if you prefer VS Code, or even $EDITOR if you want your default editor to take over.

• Finally, we can create the ZSH widgets with the below code:

    zle -N psv
    zle -N pbv
  

  Note: I chose the functions psv and pbv to be named as such (declared previously) to represent a mnemonic, i.e: preview-side-vi and preview-bottom-view.

• And bind the shortcut keys with this:

    bindkey '^P' psv
    bindkey '^O' pbv
  

If you want to dig deeper, please feel free to look under the hood in my dotfiles: github.com/raisedadead/dotfiles.

I hope you liked this story, until the next one.