Before, we had the focus on attributes and how they were impacted by
various features. Now we separate out language items and put both magic
and raw attributes under the type of attribute (command, arg, etc)
This is part of the `App` rename.
Previously, I was concerned about not being able to deprecate
For backwards compatibility, we still expose the `IntoApp` name.
No good solution for transitioning the trate name, unfortnately, since
we can't mark `use`s as deprecated (we can, it just does nothing).
I got rid of the `into` prefix because that implies a `self` parameter
that doesn't exist.
Like was said in #2435, this is what people would expect.
While we should note this in a compatibility section in the changelog, I
do not consider this a breaking change since we should be free to adjust
the help output as needed. We are cautious when people might build up
their own content around it (like #3312) but apps should already handle
this with `--help` so this shouldn't be a major change.
We aren't offering a way for people to disable this, assuming people
won't need to. Longer term, we are looking at support "Actions" (#3405)
and expect those to help customize the flags. We'll need something
similar for the `help` subcommand.
Fixes#3440
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.
For the derive API, you can only call `next_display_order` when dealing
with a flatten. Until we offer app attributes on arguments, the user can workaround with
this no-op flattens.
This is a part of #1807
