A couple of things happened when preparing to release 3.0
- We needed derive documentation
- I had liked how serde handled theres
- I had bad experiences finding things in structopt's documentation
- The examples were broken and we needed tests
- The examples seemed to follow a pattern of having tutorial content and
cookbook content
- We had been getting bug reports from people looking at master and
thinking they were looking at what is currently released
- We had gotten feedback to keep down the number of places that
documentation was located
From this, we went with a mix of docs.rs and github
- We kept the number of content locations at 2 rather than 3 by not
having an external site like serde
- We rewrote the examples into explicit tutorials and cookbooks to align
with the 4 styles of documentation
- We could test our examples by running `console` code blocks with
trycmd
- Documentation was versioned and the README pointed to the last release
This had downsides
- The tutorials didn't have the code inlined
- Users still had a hard time finding and navigating between the
different forms of documentation
- In practice, we were less likely to cross-link between the different
types of documentation
Moving to docs.rs would offer a lot of benefits, even if it is only
designed for Rust-reference documentation and isn't good for Rust derive
reference documentation, tutorials, cookbooks, etc. The big problem was
keeping the examples tested to keep maintenance costs down. Maybe its
just me but its easy to overlook
- You can pull documentation from a file using `#[doc = "path"]`
- Repeated doc attributes get concatenated rather than first or last
writer winning
Remember these when specifically thinking about Rust documentation made
me realize that we could get everything into docs.rs.
When doing this
- Tutorial code got brought in as was one of the aims
- We needed to split the lib documentation and the README to have all of
the linking work. This allowed us to specialize them according to
their rule (user vs contributor)
- We needed to avoid users getting caught up in making a decision
between Derive and Builder APIs so we put the focus on the derive API
with links to the FAQ to help users decide when to use one or the
other.
- Improved cross-referencing between different parts of the
documentation
- Limited inline comments were added to example code
- Introductory example code intentionally does not have teaching
comments in it as its meant to give a flavor or sense of things and
not meant to teach on its own.
This is a first attempt. There will be a lot of room for further
improvement. Current know downsides:
- Content source is more split up for the tutorials
This hopefully addresses #3189
When upgrading our company projects from clap 3.1 to clap 3.2 I had
to fix several references to `clap::lazy_init`. People are not
supposed to do that, but that's hard to enforce.
Hope placing `once_cell` reexport into `__macro_refs` prevent at
least some of the such issues in the future.
This adds a new `Cargo.toml` feature named `deprecated` that opts
controls whether deprecation warnings show up. This is starting off as
non-default though that may change (see below).
Benefits
- Allows a staged rollout so a smaller subset of users see new
deprecations and can report their experience with them before everyone
sees them. For example, this reduces the number of people who have to
deal with #3822.
- This allows people to defer responding to each new batch of
deprecations and instead do it at once. This means we should
reconsider #3616.
The one risk is people who don't follow blog posts and guides having a
harder time upgrading to the next breaking release without the warnings
on by default. For these users, we reserve the right to make the
`deprecated` feature `default`. This is most likely to happen in a
minor release that is released in conjunction with the next major
release (e.g. when releasing 4.0.0, we release a 3.3.0 that enables
deprecations by default). By using a feature, users can still disable
this if they want.
Thanks @joshtriplett for the idea
Though this is changing an API item we export, we do not consider this a
breaking change because
- This was an implementation detail of the macros and people shouldn't be using it directly
- The `macro_rules` macro is coupled to `clap` because they are in the
same crate
- The derive macro is coupled to `clap` because `clap` declares a
`=x.y.z` dependency on `clap_derive
Fixes#3828
We aren't enumerating arguments but values for an argument, so the name
should reflect that.
This will be important as part of #1807 when we have more specific
attribute names.
The top-level API for clap is getting a bit bloated. By exposing these
modules, we'll be able to continue to add new, less commonly used types
while keeping the main API focused.
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.
We left them in the docs for a period of time to help people find docs
for code that was still in use. Balancing that with the need for clean
docs, it seems like 3.1 is an appropriate time to mark them hidden in
the docs.
Confirmed this works with [`argfile`](https://docs.rs/argfile/latest/argfile/)
And then running in clap
```
$ RUSTDOCFLAGS="--cfg docsrs" cargo +nightly doc --all-features
```
They now show up!
- Some still referenced the clapng issue number
- Some YAML ones were missed in the formatting clean up
- I never updated the usage ones with the formatting clean up
Before, we limited it to the `doc` feature because of how extensive the
README was. It has since scaled back, so we can be more selective with
what features enable it.
Until we have a modular help generator that can be configured and/or
authored by the users themselves as part of #2914, we will provide the
flexibility of turning off colored help messages but still wanting
colored error messages.
This flexibility was available before #2845 and @dbrgn immediately
noticed it and requested it back to which I agree. This was also
suggested by Josh in
[here](https://github.com/clap-rs/clap/issues/2806#issuecomment-933877438)
Adding in a `StructOpt` derive with `structopt` attributes, with
deprecation notices. Unofrtunately, not as many deprecation warnings as
I would like. Apparently, you can't do them for a `use` of a derive? I
also wanted to inject code that would trigger a deprecation notice for
attributes but that would require enough of a refactor that I didn't
consider it worth it. We are at least providing a transition window
even if it means we'll have to remvoe it next major release without a
deprecation warning.
Since usage parser and yaml are on the way to being deprecated (#8, #9),
doing a rename also seems excessive, so rolling it back.
Past relevant PRs:
- clap-rs/clap#1157
- clap-rs/clap#1257
While in some cases "branches-sharing-code" might catch bugs, it overall encourages a form
of DRY that leads to bad code. In this specific case, it is relying on
the implementation detail of the formatting of each branch being the
same. If the `'` wasn't part of it, I could see it being about a shared
`?` to go with the shared start of the question.
In considering potential work for #2683, I realized we might need a type to carry data for
each of the `multiple_values`. `ArgValue` works both for that and for
possible values, so we need to come up with a better name for one or
both. Changing `ArgValue`s name now would be ideal since its new in
clap3 and by renaming it, we can reduce churn for users.
While thinking about this, I realized I regularly get these mixed
up, so renaming `ArgValue` to `PossibleValue` I think will help clear
things up, regardless of #2683.
- `App::with_defaults` was not included since that has been deprecated
since 2.14
- `App::args_from_usage` does not have a close enough parallel in the
new API, as far as I could tell
- `ArgMatches::usage` cannot have a thin wrapper around
`App::generate_usage`.
- `App::write_*`: getting lazy, didn't seem like high value functions
- Any `Settings` (some things need to be figured out here)
This is a part of #2617
Before #2005, `Clap` was a special trait that derived all clap traits it
detected were relevant (including an enum getting both `ArgEnum`,
`Clap`, and `Subcommand`). Now, we have elevated `Clap`, `Args`,
`Subcommand`, and `ArgEnum` to be user facing but the name `Clap` isn't
very descriptive.
This also helps further clarify the relationships so a crate providing
an item to be `#[clap(flatten)]` or `#[clap(subcommand)]` is more likely
to choose the needed trait to derive.
Also, my proposed fix fo #2785 includes making `App` attributes almost
exclusively for `Clap`. Clarifying the names/roles will help
communicate this.
For prior discussion, see #2583
