What does shell --fancy do?

[isaacl]

What exactly does pipenv shell --fancy do?

Also, I notice the omz pipenv plugin does not use it. Should it have an option?

[matteius]

From reading the code, for windows, it is always "fancy" and other systems the flag determines whether we invoke the shell with the logic of shell.fork(*fork_args) and otherwise it tries shell.fork_compat(*fork_args) and if that fails falls back to shell.fork(*fork_args). I'd like if eventually we can deprecate the --fancy argument and consolidate the shell fork logic into a single code path, it seems close already.

[isaacl]

My read was the shell.fork execs into a shell process, while shell.fork_compat stays involved in every keystroke using pexpect.

So in theory, shell.fork should be more efficient, especially for large amounts of output.

Related pyenv patch -- to support using --fancy with pyenv.

However I still haven't gotten --fancy to fully work.