A flexible way to process the result of customized search with fzf

[xuhdev]

The Turning into a Different Process section in README
makes a lot of arguments on why a binding such as enter:become(vim {}) is
beneficial. These benefits are totally valid and useful in many cases. However,
in most cases, I found the following trick is more flexible and powerful than
adding the desired program to enter:become, at least in zsh.

Let's say we would like to let fzf search for a file in a certain way and let
an editor to open it.

1. Create a zsh function and fill in FZF_CTRL_T_COMMAND and
   FZF_CTRL_T_OPTS with the desired values, then call fzf-file-widget.
2. Don't hard code any program like vim, emacs, or less.
3. Turn this function into a zsh widget by calling zle -N function-name.
4. To use this this widget, type your editor's name + space, then call this
   widget.

For example, this instruction shows how to integrate rg and fzf, and use Vim to open the desired search
result. The code snippet can be rewritten to:

function my-fzf-find-file-in-cwd () {
  # 1. Search for text in files using Ripgrep
  # 2. Interactively restart Ripgrep with reload action
  # 3. Add the file to zsh buffer
  RG_PREFIX="rg --column --line-number --no-heading --color=always --smart-case "
  INITIAL_QUERY="${*:-}"
  FZF_CTRL_T_COMMAND=
  FZF_CTRL_T_OPTS="--ansi --disabled --query '$INITIAL_QUERY' \
      --bind 'start:reload:$RG_PREFIX {q}' \
      --bind 'change:reload:sleep 0.1; $RG_PREFIX {q} || true' \
      --delimiter : \
      --preview 'bat --color=always {1} --highlight-line {2}' \
      --preview-window 'up,60%,border-bottom,+{2}+3/3,~3' \
      --bind 'enter:become(echo {1})'"  # Add +{2} to also show line number
  fzf-file-widget
}
zle -N my-fzf-find-file-in-cwd
bindkey -M emacs "^XP" my-fzf-find-file-in-cwd

Now the command is no longer limited to be usable by Vim. I can use it in any
command, such as using an editor:

$ $EDITOR [Ctrl-X Shift-P]

or a different command:

$ git log [Ctrl-X Shift-P]

or multiple times:

# Show the differences between two branches of files of interest
$ git diff my-branch master -- [Ctrl-X Shift-P] [Ctrl-X Shift-P]

Hope this helps!