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.
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
Putting it on the doc comment is weird. We are now putting it on the
field which is a slight improvement. This better conveys "this is
auto-generated".
No test was added because the use case that I know of for exposing this
is short lived.
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.
For programs opting into the clap v4 behavior (with `action` or
`value_parser` attributes), we'll no longer generate a
`multiple_occurrences(true)` call in preparation for deprecating
`multiple_occurrences`. See #3772.
This is the derive support for #3774 (see also #3775, #3777)
This combined with `value_parser` replaces `parser`. The main
frustration with this is that `ArgAction::Count` (the replacement for
`parse(from_occurrences)` must be a `u64`. We could come up with a
magic attribute that is meant to be the value parser's parsed type. We
could then use `TryFrom` to convert the parsed type to the user's type
to allow more. That is an exercise for the future. Alternatively, we
have #3792.
Prep for this included
- #3782
- #3783
- #3786
- #3789
- #3793
This will make it easier to divide off parser logic for adding in
actions.
This does mean we can't provide error reporting on bad values with
`bool` but
- We should have also been doing that for `from_flag`
- We'll be dropping this soon in clap4 anyways
Clap has focused on reporting development errors through assertions
rather than mixing user errors with development errors. Sometimes,
developers need to handle things more flexibly so included in #3732 was
the reporting of value accessor failures as internal errors with a
distinct type. I've been going back and forth on whether the extra
error pessimises the usability in the common case vs dealing with the
proliferation of different function combinations. In working on
deprecating the `value_of` functions, I decided that it was going to be
worth duplicating so long as we can keep the documentation focused.
The remove functions no longer return `Arc` but the core type, at the
cost of requiring `Clone`. I originally held off on this
in #3732 in the hope of gracefully transition the derive and requiring
`Clone` would have been a breaking change but when it came to #3734, I didn't
find a way to make it work without a breaking change, so I made it
opt-in. This means I can force the `Clone` requirement now.
I added the requirement for `Clone` everywhere else in the hopes that in
the future, we can drop the `Arc` without a breaking change.
For clap 3, its opt-in as a precaution against breaking
compatibility in some weird cases.
This does require the types to implement `Clone`.
Fixes#3734Fixes#3496Fixes#3589
In case the `ArgMatches` is cloned, this forces a constraint that the
underlying type impls `Clone` but that should be safe as we only support
`String` and `OsString`.
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.
Now that we can use `SubcommandRequired |
ArgRequiredElseHelp`, this setting offers little value but requires we
track required subcommands with two different settings. Deprecating as
the cost is not worth the benefit anymore.
Issue #3280 will see the derive updated
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
This clarifies the intent and prepares for other functions doing the
same, like `next_display_order`. This will then open us to name
`subcommand_help_heading` and `display_order` similar.
The deprecation is waiting on 3.1.
This is part of #1807 and #1553.
The error was when doing `#[clap(arg_enum, default_value_t = ...)]`.
Good example of why we should minimize `use`, at least in tests
(besides reducing merge conflicts, code churn, etc).
While I'm unsure how much type specialization we should do, we
intentionally have the `arg_enum` attribute for doing special behavior
based on it, so let's take advantage of it.
Fixes#3185
The main care about is that when we override a `flatten` / `subcommand`
doc comment in a parent container, that we make sure we take nothing
from the child container, rather than implicitly taking one `about` ut
not `long_about`.
To do this, and to play the most safe with long help detection, we reset
`long_about` to default when there is no doc comment body to use for
`long_about`.
Fixes#2983
Experimenting with treating clap-derive and clap one and the same from
the release process perspective. The completion generators are a bit
more independent.
This contains two types of re-ordering:
- Internal, putting the focus of each file first.
- Public, re-arranging items and grouping impl blocks to try to better
organize the documentation and find related items.
The main weakness of the docs work is in `Args`. Its just a mess. In
particular, we should probably link the simple casesm like `required` to
the advanced impl block.
Fixes#55
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.
This creates distinct tutorial examples from complex feature examples
(more how-tos). Both sets are getting builder / derive versions (at
least the critical ones).
I've been finding I've been setting `AppSettings` without it which is
likely leading to bugs. This tries to raise the visibility by using it
based on the setting being used and not whether the application needs
it.
Before:
- `bool`: a flag
- `Option<_>`: not required
- `Option<Option<_>>` is not required and when it is present, the value
is not required
- `Vec<_>`: multiple values, optional
- `Option<Vec<_>>`: multiple values, min values of 0, optional
After:
- `bool`: a flag
- `Option<_>`: not required
- `Option<Option<_>>` is not required and when it is present, the value
is not required
- `Vec<_>`: multiple occurrences, optional
- optional: `Vec` implies 0 or more, so should not imply required
- `Option<Vec<_>>`: multiple occurrences, optional
- optional: Use over `Vec` to detect when no option being present when
using multiple values
Motivations:
My priorities were:
1. Are we getting in the users way?
2. Does the API make sense?
3. Does the API encourage best practices?
I was originally concerned about the lack of composability with
`Option<Option<_>>` and `Option<Vec<_>>` (and eventually `Vec<Vec<_>>`).
It prescribes special meaning to each type depending on where it shows
up, rather than providing a single meaning for a type generally. You
then can't do things like have `Option<_>` mean "required argument with
optional value" without hand constructing it. However, in practice the
outer type correlates with the argument occurrence and the inner type
with the value. It is rare to want the value behavior without also the
occurrence behavior. So I figure it is probably fine as long as people
can set the flags to manually get the behavior they want.
`Vec<_>` implies multiple occurrences, rather than multiple values.
Anecdotally, whenever I've used the old `Arg::multiple`, I thought I was
getting `Arg::multiple_occurrences` only. `Arg::multiple_values`,
without any bounds or delimiter requirement, can lead to a confusing
user experience and isn't a good default for these. On top of that, if
someone does have an unbounded or a delimiter multiple values, they are
probably also using multiple occurrences.
`Vec<_>` is optional because a `Vec` implies 0 or more, so we stick to
the meaning of the rust type. At least for me, I also rarely need a
required with multiple occurrences argument but more often need optional
with multiple occurrences.
`Option<Vec<_>>` ends up matching `Vec<_>` which can raise the question
of why have it. Some users might prefer the type. Otherwise, this is
so users can detect whether the argument is present or not when using
`min_values(0)`. Rather than defining an entire policy around this and
having users customize it, or setting `min_values(0)` without the rest
of a default policy, this gives people a blank slate to work from.
Another design option would have been to not infer any special-type
settings if someone sets a handful of settings manually, which would
have avoided the confusion in Issue clap-rs/clap 2599 but I see that
being confusing (for someone who knows the default, they will be
expecting it to be additive; which flags disable inferred settings?) and
brittle (as flags are added or changed, how do we ensure we keep this
up?).
Tests were added to ensure we support people customizing the behavior to
match their needs.
This is not solving:
- `Vec<Vec<_>>`, see clap-rs/clap 2924
- `(T1, T2)`, `Vec<(T1, T2)>`, etc, see clap-rs/clap 1717
- `Vec<Option<_>>` and many other potential combinations
Fixes clap-rs/clap 1772
Fixes clap-rs/clap 2599
See also clap-rs/clap 2195
This reverts commits 24cb8b1..d0abb37 from clap-rs/clap#1840
This is part of #16. clap-rs/clap#1840 wasn't the right call but we
don't have time to make the decision now, so instead of having one
option and changing it in 4.0, this reverts back to clap2 behavior.
Looks like this is coming from `update_from_arg_matches` where we do a
ladder of `if __clap_arg_matches.is_present(...)` that clippy wants to
be `else if`s. While for human edited code, that does clarify intent,
for machine generated code that is rarely read, its a pain to do, so
silencing it.
Unfortunately, it isn't in a group we can overall silence.
Fixes#3017
In experimenting on #1772, I want to write test cases for various
combinations of required or not, values vs occurrences, etc. There
wasn't really a clear place to put these.
On top of that, I wanted there to be a clear place in the tests for
describing the behavior of special types, to make it easier to audit and
easier to see how a PR for #1772 changes things.
As part of this effort in organizing these tests, I reduced the number
of tests that use special types. This better focuses these tests on the
cases they are intending to cover, rather than pulling in unrelated
features. This makes it easier to audit special types and makes it so
failures give more focused results, making it easier to see what broke.
PR #2979 reduced what dependencies we push on users and made us one step
closer to being able to test more with fewer features. Looks like I
also need to update `clap_derive`. I verified locally that #2976 fails
with this.
`clap_derive` still needs `env` because of examples / tests that use it.
I feel like moving `clap_derive`s tests out to `clap` would be the way
to fix this.
