With `number_of_values` being per-occurrence now, its doesn't make sense
for `number_of_values(0)` to set `takes_value(true)` or for
`number_of_values(1)` to set `multiple_values(true)`.
In addition, an assert is made if the user works around this
This both simplifies the code and the model we present to the user,
making more sense.
There is room for further exploration of tying flag actions into this.
This changes the default type as well to encourage preserving the full
information for shelling out. If people need UTF-8, then they can
change the value parser.
Fixes#3733
Previous behavior:
- They'd be sorted by default
- They'd derive display order if `DeriveDisplayOrder` was set
- This could be set recursively
- The initial display order value for subcommands was 0
New behavior:
- Sorted order is derived by default
- Sorting is turned on by `cmd.next_display_order(None)`
- This is not recursive, it must be set on each level
- The display order incrementing is mixed with arguments
- This does make it slightly more difficult to predict
We had some tests for this but not sufficient obviously. The problem is
we were tweaking the positional argument counter when processing flags
and not just positional arguments. Delaying it until after flags seems
to fix this.
Fixes#3959
This fixes a bug introduced in 4a694f3592
when we were trying to move away from presence checks via occurrences.
I switched it to the common type of presence check but really what we
want is a highest-precedence check.
Fixes#3872
Someone should not reasonably expect a coun flag to go up to billions,
millions, or even thousands. 255 should be sufficient for anyone,
right?
The original type was selected to be consistent with
`ArgMatches::occurrences_of` but that is also used for tracking how
many values appear which can be large with `xargs`.
I'm still conflicted on what the "right type" is an wish we could
support any numeric type. When I did a search on github though, every
case was for debug/quiet flags and only supported 2-3 occurrences,
making a `u8` overkill.
This came out of a discussion on #3792
This mostly exist for
- Knowing of the value came from the command-line but we now have
`ArgMatches::source`
- Counting the number of flags but we now have `ArgAction::Count`
This shouldn't be needed anymore now that this is effectively the new
behavior for the non-deprecated actions.
This was briefly talked about in
https://github.com/clap-rs/clap/discussions/2627 but I wasn't familiar
enough with the implementation to know how safe it is. Now, maintainrs
and users can be more confident because they are explicitly opting into
it.
See also #3795
This is a follow up to #3420. Its easy to overlook this because it is only
useful for the conditionals (we actually prevent applying unconditional
defaults to unconditional requireds). This became apparent with the
increased use of defaults with `SetTrue`.
As always, there is the question of when is a bug fix a breaking change.
I'm going to consider this safe since we prevent some instances of this
from even happening and we already did #3420 and this is in line with
those.
Actions were inspired by Python and Python does not implicitly default
any field when an action is given. From a Builder API perspective, this
seemed fine because we tend to focus the Builder API on giving the user
all information so they can make their own decisions. When working on
the Derive API, this became a problem because users were going to have
to migrate from an implied default to an explicit default when a common
default is good enough most of the time. This shouldn't interfere with
Builder users getting more details when needed.
This also highlighted two problems
- We set the index for defaults
- We don't debug_assert when applying conditional requirements with a
default present
This round out the new style actions and allow us to start deprecating
occurrences.
As part of an effort to unify code paths, this does change flag parsing
to do splits. This will only be a problem if the user enables splits
but we'll at least not crash. Once we also address #3776, we'll be able
to have envs all work the same.
If we felt this was important long-term, we should fix this outside of
the Action. Since we might be changing up occurrences (#3772), we can
probably get away with a hack.
This changes how occurrences and values are grouped for multiple values.
Today, it appears as a bug. If we move forward with #3772, then this
can make sense.
I wrote these tests expecting to highlight a bug but it turns out things
were structured just right to not exhibit it. The fact that the code
looks like its broken is a problem, so I restructured it (put it first,
changed the source) so it doesn't look suspicious anymore.
We were independently starting occurrences and starting value groups.
Now we do them at the same time.
COMPATIBILITY: This changes us from counting occurrences per positional
when using `multiple_values` to one occurrence. This is user visible
and tests were written against it but it goes against the documentation
and doesn't quite make sense.
When to show usage? We are currently mixed about it. For `validator`,
we didn't show it at all. Sometimes we show the used arguments and
sometimes we don't.
With `ValueParser`, I ran into the problem that we weren't showing the
used arguments like we had previously in some cases. In deciding how to
solve this, I went with the simplest route for now and removed it as the
usage likely doesn't add much context to help people solve their
problem, more so the recommendation for help. We'll see how the
feedback is on this and adjust.
`multicall` allows you to have one binary expose itself as multiple
programs, like busybox does. This also works well for user clap for
parsing REPLs.
Fixes#2861
Unfortunately, we can't track using a `ValueParser` inside of `Command`
because its `PartialEq`. We'll have to wait until a breaking change to
relax that.
Compatibility:
- We now assert on using the wrong method to look up defaults. This
shouldn't be a breaking change as it'll assert when getting a real
value.
- `values_of`, et al delay panicing on the wrong lookup until the
iterator is being processed.
With us moving the required de-duplication up a level, it made this
check redundant. By removing this check, we're more likely to have an
item in the `incls` which forces a smart usage and reduces the chance of
an `[ARGS]` or `[OPTIONS]`, so a couple of tests changed.
Gave up trying to decipher the existing logic for safe ways to
de-duplicate manually and switched to an `IndexSet` to enforce only one
of each argument exists.
Fixes#3556
This is a step towards #3309. We want to make longs and long aliases
more consistent in how they handle leading dashes. There is more
flexibility offered in not stripping and it matches the v3 short
behavior of only taking the non-dash form. This starts the process by
disallowing it completely so people will catch problems with it and
remove their existing leading dashes. In a subsequent breaking release
we can remove the debug assert and allow triple-leading dashes.
`Arg::exclusive` is just another way of defining conflicts, so a
present-exclusive arg should override required like other conflicts.
Instead of going through the message of enumerating all other arguments
as exclusive, I shortcutted it and special case exclusive in the
required check like we do with conflicts. The big downside is the
implicit coupling between the code paths rather than having a consistent
abstraction for covering conflicts.
This isn't a breaking change because if someone defined an exclusive arg
as a sibling to a required arg, the exclusive arg could never be used,
it always errored, and so no valid application can be written with it.
Fixes#3595
This is a step towards #992. When help renders the application name, it
uses the `bin` template variable which is just the `bin` name with
spaces converted to ` `. While having `app.exe sub` makes sense,
`app.exe-sub` does not.
To get around needing this for usage, we've created a `display_name`
field that is fairly similar but
- The root name is the `name` and not `bin_name`
- We always join with `-`
This means that the derived `bin_name` will only show up in usage.
For now, the default template has not been updated as that is a minor
compatibility change and should be in a minor release, at least. I was
worried this would be a full breaking change. The main case I was
worried about was cargo subcommands but our tests show they should just
work.
