Is it possible to manually trigger fzf completion in bash?

[kaddkaka]

In bash, can I invoke the fuzzy completion from code so that I can skip the ** trigger altogether?

I would like fruits<TAB> to behave as fruits **<TAB>.

Actually I would prefer it to expand to fruits="<selected items>".

complete -F my_completion fruits
my_completion() {
    //fzf invokation 
} 
my_completion_post() {} 

Is something like that possible?

[ghost]

Set FZF_COMPLETION_TRIGGER empty.

export FZF_COMPLETION_TRIGGER=''

Customizing fzf options for completion

[kaddkaka]

I want the resulting completed prompt to look like fruits="item1:otem2" after selecting two items.

This is for environment variable setup. I already got a solution for gluing them together with colon.

[ghost]

I see.
I'm testing fruits<TAB> with lincheney/fzf-tab-completion.

demo.mp4

And here's the config.

# .bashrc
eval "$(fzf --bash)"

source "$HOME/.config/fzf/fzf-bash-completion.sh"
if [[ "$PS1" ]]; then
	# shell is interactive
	bind -x '"\t": fzf_bash_completion'
fi

eval "$(declare -f fzf_bash_completion | sed '1s/fzf_bash_completion/_orig_fzf_bash_completion/')"

fzf_bash_completion() {
	if [[ "${READLINE_LINE:0:READLINE_POINT}" =~ ^[[:space:]]*fruits[[:space:]]*$ ]]; then
		_custom_fruits_fzf
		return
	fi
	_orig_fzf_bash_completion
}

_custom_fruits_fzf() {
	local selected joined
	selected="$(printf '%s\n' apple banana cherry grape orange strawberry | fzf --multi --height=40% --reverse)"
	if [[ -n "$selected" ]]; then
		joined="$(echo "$selected" | paste -sd':' -)"
		READLINE_LINE="fruits=\"${joined}\""
		READLINE_POINT=${#READLINE_LINE}
	fi
	printf '\r'
	command tput el 2> /dev/null || echo -ne "\033[K"
}

[kaddkaka]

Thanks, I was already using https://github.com/lincheney/fzf-tab-completion, this technique seems promising.

I tried the following, but calling _fzf_complete_fruit has no effect.

my_complete () {
  if [[ "$READLINE_LINE" == "" ]]; then
    READLINE_LINE=fruit
    READLINE_POINT=${#READLINE_LINE}
  elif [[ "$READLINE_LINE" == fruit* ]]; then
    _fzf_complete_fruit
  else
    fzf_bash_completion
  fi
}
bind -x '"\es": my_complete'

# https://github.com/junegunn/fzf?tab=readme-ov-file#custom-fuzzy-completion
_fzf_complete_fruit() {
  _fzf_complete --with-nth=1 --multi --reverse --prompt="fruit> " -- "$@" < <(
    echo smultron
    echo tistron
    echo hallon
    echo lingon
    echo hjortron "(cloudberry)"
    echo krikon
  )
}
_fzf_complete_fruit_post() {
  tr '\n' ':'
}
[ -n "$BASH" ] && complete -F _fzf_complete_fruit -o default -o bashdefault fruit

[kaddkaka]

I see. I'm testing fruits<TAB> with lincheney/fzf-tab-completion.

demo.mp4
And here's the config.

# .bashrc
eval "$(fzf --bash)"

source "$HOME/.config/fzf/fzf-bash-completion.sh"
if [[ "$PS1" ]]; then
	# shell is interactive
	bind -x '"\t": fzf_bash_completion'
fi

eval "$(declare -f fzf_bash_completion | sed '1s/fzf_bash_completion/_orig_fzf_bash_completion/')"

fzf_bash_completion() {
	if [[ "${READLINE_LINE:0:READLINE_POINT}" =~ ^[[:space:]]*fruits[[:space:]]*$ ]]; then
		_custom_fruits_fzf
		return
	fi
	_orig_fzf_bash_completion
}

_custom_fruits_fzf() {
	local selected joined
	selected="$(printf '%s\n' apple banana cherry grape orange strawberry | fzf --multi --height=40% --reverse)"
	if [[ -n "$selected" ]]; then
		joined="$(echo "$selected" | paste -sd':' -)"
		READLINE_LINE="fruits=\"${joined}\""
		READLINE_POINT=${#READLINE_LINE}
	fi
	printf '\r'
	command tput el 2> /dev/null || echo -ne "\033[K"
}

I see. I'm testing fruits<TAB> with lincheney/fzf-tab-completion.

demo.mp4
And here's the config.

# .bashrc
eval "$(fzf --bash)"

source "$HOME/.config/fzf/fzf-bash-completion.sh"
if [[ "$PS1" ]]; then
	# shell is interactive
	bind -x '"\t": fzf_bash_completion'
fi

eval "$(declare -f fzf_bash_completion | sed '1s/fzf_bash_completion/_orig_fzf_bash_completion/')"

fzf_bash_completion() {
	if [[ "${READLINE_LINE:0:READLINE_POINT}" =~ ^[[:space:]]*fruits[[:space:]]*$ ]]; then
		_custom_fruits_fzf
		return
	fi
	_orig_fzf_bash_completion
}

_custom_fruits_fzf() {
	local selected joined
	selected="$(printf '%s\n' apple banana cherry grape orange strawberry | fzf --multi --height=40% --reverse)"
	if [[ -n "$selected" ]]; then
		joined="$(echo "$selected" | paste -sd':' -)"
		READLINE_LINE="fruits=\"${joined}\""
		READLINE_POINT=${#READLINE_LINE}
	fi
	printf '\r'
	command tput el 2> /dev/null || echo -ne "\033[K"
}

Is there any reason you override the name fzf_bash_completion instead just creating your own name? To make it easier to distribute to other who have fzf_bash_completion?

I almost always see the --reverse used, why?

I wonder if it would be possible to "patch" regular readline completion like this. I haven't been able to find a way to invoke that.

Perhaps one should feedback \t into bash as input to trigger whatever default behavior is. Not sure that's possible either though.

[ghost]

Is there any reason you override the name fzf_bash_completion instead just creating your own name? To make it easier to distribute to other who have fzf_bash_completion?

Cause that fzf_bash_completion function I tested was coming from lincheney/fzf-tab-completion.
We sure can change the name but if we did, we also need to edit fzf-bash-completion.sh.

I almost always see the --reverse used, why?

Option --reverse is just a layout about input stream orders, nothing special.
I guess many users prefer the --reverse option because that's usually the order terminals display things.

I wonder if it would be possible to "patch" regular readline completion like this. I haven't been able to find a way to invoke that.

Perhaps one should feedback \t into bash as input to trigger whatever default behavior is. Not sure that's possible either though.

How about this approach that uses bind chains.

# .bashrc
eval "$(fzf --bash)"

_custom_fruits_fzf() {
	local selected joined
	selected="$(printf '%s\n' apple banana cherry grape orange strawberry | fzf --multi --height=40% --reverse)"
	if [[ -n "$selected" ]]; then
		joined="$(echo "$selected" | paste -sd':' -)"
		READLINE_LINE="fruits=\"${joined}\""
		READLINE_POINT=${#READLINE_LINE}
	fi
	printf '\r'
	command tput el 2> /dev/null || echo -ne "\033[K"
}

__fruits_tab_handler() {
	if [[ "${READLINE_LINE:0:READLINE_POINT}" =~ ^[[:space:]]*fruits[[:space:]]*$ ]]; then
		_custom_fruits_fzf
		bind '"\C-x\C-b": ""'
	else
		bind '"\C-x\C-b": complete'
	fi
}

bind -x '"\C-x\C-a": __fruits_tab_handler'
bind '"\C-x\C-b": complete'
bind '"\t": "\C-x\C-a\C-x\C-b"'