Fuzzy find Neovim buffers globally

fzfbuf.sh

#!/bin/bash

# Globally fuzzy search Neovim buffer filenames,
# across all Tmux panes.

# Requires: fzf, nvim, tmux, bash
# Optional: bat, eza

# Only tested on Fedora Linux
# https://gist.github.com/mikeslattery/444f4fef4a20cfe786ba323a081262f7

set -u

SOCKETDIR="/run/user/$(id -u)"
if ! find "$SOCKETDIR" -maxdepth 1 -type s -name 'nvim.*.0' -print -quit 2>/dev/null | grep -sq .; then
    # macOS/BSD/WSL1/Cygwin/MSys2 logic: Neovim usually places sockets in a subdirectory of TMPDIR named after the user.
    SOCKETDIR="${TMPDIR:-/tmp}/nvim.$(id -un)"
fi

get_nvim_sockets() {
    _checksocket() {
        if nc -z -U "$1"; then
            echo "$1"
        else
            rm "$1"
        fi
    }

    # Find sockets matching the pattern nvim.PID.0 and extract the PID.
    for socket in $(find "$SOCKETDIR" -maxdepth 1 -type s -name 'nvim.*.0'); do
        _checksocket "$socket" &
    done
    wait
}

# 1=socket, 2=expression
expr() {
    nvim --clean --headless --server "$1" --remote-expr "$2"
    echo
}

getlist() {
    _getlistline() {
        socket="$1"
        # Query the specific Neovim instance for the TMUX_PANE environment variable it was started in.
        # Convert the unique pane ID into a human-readable Session:Window.Pane format.
        pane="$(expr "$socket" 'system("echo -n \"$PPID \"; tmux display-message -t $TMUX_PANE -p \"#S:#I.#P\"")')"

        # Get all buffer numbers.
        # Filter for listed buffers (buflisted).
        # Get the absolute path (:p) for each buffer name.
        # Join with newlines and prefix with PID and Pane info for fzf.
        expr "$socket" 'join(map(filter(range(1, bufnr("$")), "buflisted(v:val)"), "getftime(bufname(v:val)) . \" \" . fnamemodify(bufname(v:val), \":p\")"), "\n")' |
            sed "s/$/ ${pane}/"
    }
    {
        # Iterate through all active Neovim server sockets.
        for socket in $(get_nvim_sockets); do
            _getlistline "$socket" &
        done
        wait
    } | grep -v -- '^-1' | sort -r | awk '{print $3, $4, $2}'
}

focus_buffer() {
    local pane="$1"
    local socket="$2"
    local file="$3"

    tmux select-pane -t "$pane" -Z \; select-window -t "$pane" \; switch-client -t "${pane}" &
    expr "$socket" "execute('b $file')" | sed '$d' &
    wait
}

main() {

    # Pipe the list into fzf with a dynamic preview.
    # If the selection is a directory, use eza/ls; if a file, use bat/cat.
    pickline="$(getlist | fzf --preview-window 'right:50%,<80(hidden)' --preview '
        if [ -d {3} ]; then
            eza -lT --color=always {3} 2>/dev/null || ls -la {3}
        else
            bat --color=always --style=numbers {3} 2>/dev/null || cat {3}
        fi
    ')"

    if [ -n "$pickline" ]; then
        # Parse the PID, Tmux pane, and File path from the fzf selection.
        pid=$(echo "$pickline" | awk '{print $1}')
        pane=$(echo "$pickline" | awk '{print $2}')
        file=$(echo "$pickline" | awk '{print $3}')

        socket="${SOCKETDIR}/nvim.${pid}.0"

        # Focus the correct Tmux pane/window and zoom if necessary.
        # Send a remote command to the specific Neovim instance to switch to the chosen buffer.
        focus_buffer "$pane" "$socket" "$file"
    fi
}

main

TODOs:

• If buffer is in a tab+window, switch to that window instead of just blindly loading the buffer in the current window.
• Test on Mac.
• Gracefully handle dependencies not being installed: bat eza bash
• Use Lua instead of vimscript (as this thing gets more complicted)
• Other options or additional related scripts:
  • Sort buffers by most recently accessed across all neovim instances
  • Given a path as arg, go to that tmux pane + neovim buffer, with autocomplete.
  • Launch in a tmux floating window, so it can be used from inside Neovim and other TUIs
  • Search unnamed buffers
  • Output all to stdout without fzf. (for scripting)
  • Global search git ls-files across instances.
  • Global search oldfiles. (Useful if you have separate shada file per instance).
  • Fuzzy find neovim instances by working directory.
  • List duplicate buffer paths, and/or duplicate neovim working directories.
  • Do not switch sessions (in case you have two terminal apps each running a different Tmux session).
• Vim version

I do not plan to make into a neovim plugin.