bad experience when brew upgraded dependencies

[jsoref]

Last login: Tue May  2 13:46:13 on ttys217
dyld[83152]: Library not loaded: /opt/homebrew/opt/libgit2/lib/libgit2.1.5.dylib
  Referenced from: <4262F695-957A-386A-9408-5479E5DEC4BC> /Users/jsoref/.cargo/bin/jj
  Reason: tried: '/opt/homebrew/opt/libgit2/lib/libgit2.1.5.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/opt/homebrew/opt/libgit2/lib/libgit2.1.5.dylib' (no such file), '/opt/homebrew/opt/libgit2/lib/libgit2.1.5.dylib' (no such file), '/usr/local/lib/libgit2.1.5.dylib' (no such file), '/usr/lib/libgit2.1.5.dylib' (no such file, not in dyld cache), '/opt/homebrew/Cellar/libgit2/1.6.4/lib/libgit2.1.5.dylib' (no such file), '/System/Volumes/Preboot/Cryptexes/OS/opt/homebrew/Cellar/libgit2/1.6.4/lib/libgit2.1.5.dylib' (no such file), '/opt/homebrew/Cellar/libgit2/1.6.4/lib/libgit2.1.5.dylib' (no such file), '/usr/local/lib/libgit2.1.5.dylib' (no such file), '/usr/lib/libgit2.1.5.dylib' (no such file, not in dyld cache)

~/.zshrc:

if type jj &>/dev/null; then
  autoload -U compinit
  compinit
  source <(jj debug completion --zsh | sed '$d')  # remove the last line
  compdef _jj jj
fi

This happened in each window as I opened new terminals.

Once I reinstalled jj w/ the latest version (cargo install --git https://github.com/martinvonz/jj.git --locked --bin jj jujutsu), I got this:

Last login: Tue May  2 13:48:26 on ttys218
error: unrecognized subcommand 'completion'

  note: subcommand 'operation' exists
  note: to pass 'completion' as a value, use 'jj debug -- completion'

Usage: jj debug [OPTIONS] <COMMAND>

For more information, try '--help'.

Which is probably slightly better.

If there's going to be a zsh or similar instruction recommended to be added to a shell start script, going forward it should probably handle the cases where the command goes away or where the libraries are missing so that it isn't so noisy and unhelpful.

[martinvonz]

You might have figured it out by now, but jj debug completion is now called jj util completion. Also, the script it generates is different in a way that makes the way you source it different. See the updated instructions at https://github.com/martinvonz/jj#zsh.

We could deal with the command rename by keeping jj debug completion as a hidden alias. Maybe the project has enough users by now that we should have. It's just hard to tell how many users there are who are not keeping up the project on Discord and GitHub PRs, so thanks for letting us know.

The other change is harder to make compatible. I suppose we could have added a --new-zsh-variant to get the new behavior and then made that the default only a year or two later? I think the project is still too small to need that level of compatibility.

[jsoref]

So, I'd start by not using source <(jj debug completion --zsh...)

Instead, do something like:

jj_completion_script=$(mktemp)
jj_completion_errors=$(mktemp)
if jj debug completion --zsh > "$jj_completion_script" 2> "$jj_completion_errors"; then
  source | <(sed '$d' $"jj_completion_script")
fi

[jsoref]

Tentatively, I'm going to try:

if type jj &>/dev/null && jj -V &>/dev/null; then
  autoload -U compinit
  compinit
  source <(jj util completion --zsh)
fi

Which I hope will guard against the next time that jj's library dependencies break. (It won't cover the case of jj util completion --zsh crashing, but...)