ZSH and subshell has two prompts

[chrissound]

• Category
  • fzf binary
  • fzf-tmux script
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• Shell
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  • zsh
  • fish

If I run fzf within a subshell, it seems to 'prompt' twice - and the first selection is ignored. In other words, it requires two "enter" to be pressed twice on the keyboard before it returns back to the cli.

This behaviour only occurs within zsh for me - works fine in bash.

echo "$(echo 'test' | fzf)" can be used to reproduce the issue.

zsh --version
zsh 5.6.2 (x86_64-pc-linux-gnu)
fzf --version
0.17.4

[chrissound]

[junegunn]

I can't reproduce the problem on zsh 5.6.2 with fzf 0.18.0. My zshrc has only a single line, [ -f ~/.fzf.zsh ] && source ~/.fzf.zsh, so you might want to check if it's caused by some configuration.

[Mange]

I have the same issue and can replicate the problem with the above command.

fzf 0.18.0
zsh 5.7.1

› setopt
autocontinue
autopushd
autoresume
extendedglob
histignorealldups
histignorespace
histverify
interactive
kshglob
monitor
nonomatch
promptsubst
pushdignoredups
shinstdin
transientrprompt
zle

› which fzf
/usr/bin/fzf

› file /usr/bin/fzf
/usr/bin/fzf: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0,
Go BuildID=Vek4RudxVh00gKGFFHHP/yN-c3wjMGEYRSw50pnzZ/7jcep3k4gAkidOoXzm3_/rsMeRcTJtPJoND6uUG5u,
BuildID[sha1]=409413e3c41b58a1658b699aa60987d3c12a116e, stripped

[Mange]

I found my cause of the problem!

My process:

If I start zsh without loading my profile, the problem goes away. So it has to do with my settings somehow.

I found that when I uncomment a line to add a preexec hook, then the problem goes away.

In that preexec command, I try to set the title of the terminal. The title should contain the command name. This is a good hint. It might also have to do with my promptsubst option set.

I so I tried changing that part of the code:

  # From
  local terminal_title_format="$2 [%4~]"
  print -Pn "\033]0;${terminal_title_format}\007"

  # To
  (
    setopt nopromptsubst
    local terminal_title_format="$2 [%4~]"
    print -Pn "\033]0;${terminal_title_format}\007"
  )

and now there is no problem, but my terminal title still works.

I've been suffering this for weeks, but didn't really investigate until now.

[chrissound]

@Mange that sounds very similar to what I would have been doing, thanks for the write up!