Inspired by argcomplete, this provides Rust-implemented completions
- Only bash for now
- No subcommand support
- No flag value support
- No special settings support
- No handling of positions within positionals
- No prioritizing of required or removing of conflicts (including
self-conflicts)
This is a part of #2717
Some settings didn't get getters because
- They are transient parse settings (e.g. ignore errors)
- They get propagated to args and should be checked there
`is_allow_hyphen_values_set` is a curious case. In some cases, we only
check the app and not an arg. This seems suspicious.
`clap_generate` originally intended to be "generate anything". With
`fig`, we already broke one part out. With #3174's man support, we are
also looking at keeping it separate:
- More freedom to iterate on the API
- Uniqueness (and potential weight) of its dependencies
- man generation is normally more for distribution while completions are
a mix of being distributed with the app or the app generating the
completions (which will be exacerbated if we move most completion
parsing logic to be in Rust)
So `clap_generate` is having a lot more limited of a role than the
original name conveys. I worry the generic name will be a hindrance to
people discovering and using it (yes, documentation can help but there
are limits).
I hesitated because we are on the verge of releasing 3.0. However, doing
it even later will be even more disruptive because more people will be
using it (crates.io lists ~70 people using `clap_generate`).
To ease things, we are still releasing `clap_generate` as a wrapper
around `clap_complete`.
