possible conflicts with fzf

[ju1ius]

Hi,

This is a follow-up to #40. I'm opening a new issue because the older one has been closed and i've been able to come up with a reproducer.

How to reproduce

Build the following docker file docker build -t compal:gh46 .

Dockerfile

# syntax=docker/dockerfile:1.4
FROM debian:bookworm-slim

RUN <<EOS
  set -ex
  apt update && apt install -y --no-install-recommends \
    bash-completion \
    ca-certificates \
    curl \
    git
  adduser test
EOS

USER test
WORKDIR /home/test

RUN bash <<'EOS'
  set -ex
  git clone --depth=1 https://github.com/cykerway/complete-alias.git compal
  git clone --depth=1 https://github.com/junegunn/fzf.git .fzf
  ./.fzf/install
EOS

COPY <<'EOF' ./.bash_aliases
alias ls="ls --color=auto"
EOF

COPY <<'EOF' ./.bash_completion
source ~/compal/complete_alias
complete -F _complete_alias "${!BASH_ALIASES[@]}"
EOF

Run a bash session in a container:

docker run -it --rm compal:gh46 bash

On the bash prompt, type ls -<TAB>.

The shell enters an infinite loop, reapetedly outputing error: cannot unmask alias command: ls. Type <Ctrl-C> until you can go back to the prompt and exit.

How to fix

Running docker run -it --rm compal:gh46 tail .bashrc outputs:

if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi

[ -f ~/.fzf.bash ] && source ~/.fzf.bash

We can see that the fzf installation script has blindly appended it's source command. The result is that the fzf completion script is sourced after ~./bash_completion (since the latter is itself sourced at the end of /usr/share/bash-completion/bash_completion).

If we instead use the following dockerfile:

Dockerfile

# syntax=docker/dockerfile:1.4
FROM debian:bookworm-slim

RUN <<EOS
  set -ex
  apt update && apt install -y --no-install-recommends \
    bash-completion \
    ca-certificates \
    curl \
    git
  adduser test
EOS

USER test
WORKDIR /home/test

RUN bash <<'EOS'
  set -ex
  git clone --depth=1 https://github.com/cykerway/complete-alias.git compal
  git clone --depth=1 https://github.com/junegunn/fzf.git .fzf
  ./.fzf/install --no-update-rc
EOS

COPY <<'EOF' ./.bash_aliases
alias ls="ls --color=auto"
EOF

COPY <<'EOF' ./.bash_completion
source ~/.fzf.bash
source ~/compal/complete_alias
complete -F _complete_alias "${!BASH_ALIASES[@]}"
EOF

Then typing ls -<TAB><TAB><TAB> correctly shows the ls option completions, but typing ls /etc/**<TAB> does not show the fzf path completions.

If we now export COMPAL_AUTO_UNMASK=1 at the top of ~/.bash_completion, then typing ls -<TAB><TAB><TAB> correctly shows the ls option completions, and typing ls /etc/**<TAB> correctly shows the fzf path completions.

Final notes

I do not have the knowledge required to find tha actual cause of the issue, nor to tell if it's a bug in complete-alias, fzf, bash itself or just a fundamental limitation of the bash completion system...

However I think that this might warrant an entry in the docs stating that care should be taken that, in presence of other completion handlers, complete_alias should be sourced last, and that the COMPAL_AUTO_UNMASK setting may resolve some conflicts.