Add compgen.sc (cli completion generator)

[matthewweis]

Adds a standalone Slang script that can generate cli completions for the sireum command. It is completely optional, and works similar to cli.sc (except it outputs completions instead of CliOpts as JSON). The script will work for any valid cli.sc and has been placed next to the top-level cli.sc in order to generate completions for all tools when ran. It recognizes a number of special cases, such as enums and flags expecting files. Here is a demo gif.

I am happy to make any changes to the code as needed.

Example Usage:

• Add to current session only

  eval "$(sireum slang run compgen.sh)"

• Install completions in bash

  # Save to a file and source in `~/.bashrc` or `~/.bash_profile`
  sireum slang run compgen.sh > ${SIREUM_HOME}/bin/completions.sh
  echo 'source ${SIREUM_HOME}/bin/completions.sh' >> ~/.bashrc

• Install completions in zsh

  # Save to a file and source in `~/.zshrc`
  sireum slang run compgen.sh > ${SIREUM_HOME}/bin/completions.sh
  echo 'autoload bashcompinit' >> ~/.zshrc
  echo 'bashcompinit' >> ~/.zshrc
  echo 'source ${SIREUM_HOME}/bin/completions.sh' >> ~/.zshrc

[robby-phd]

It seems that it would be better to make the script as a Slash script and make the cli.sc as the script argument, then put it in the /bin directory. What do you think?

[matthewweis]

Good idea, the /bin directory does seem more appropriate. I have updated the PR accordingly and am open to any feedback. I can also make the script accept the CliOpt JSON directly (instead of invoking cli.sc from within the script) if preferable.