These didn't make sense for the builder but are helpful for the derive.
The assert was assuming people wouldn't do this and to catch internal
problems.
Fixes#4326
This originally stemmed from wrapping `Arg` in a `Box`, but we had to
smash it with a hammer as it didn't improve things enough.
- This dropped binary size by 3-7 KiB
- Parsing slowed by 20%.
- Incremental rebuilds slowed down by 1%
The styling of usage has changed in #4188 such that the usage string is on
the same line as the "Usage:" title. Previously, the usage went on the line
below the title. As such, the rules have changed for how to make a
multiline usage format correctly.
These updated rules achieve the following output for the documented
example:
Usage: myapp -X [-a] [-b] <file>
myapp -Y [-c] <file1> <file2>
myapp -Z [-d|-e]
Relates-to: #4132
If users don't want `wrap_help` feature, they can put newlines in where
needed. Seems odd to support wrapping when the wrap size is fixed. For
those hard coding the lines, this will save them a decent amount of
size.
This gives users the control over where clap outputs while still getting
colors. For users who want to support old windows versions, check out
`fwdansi` crate.
The writer is less convenient and isn't offering any performance
benefits of avoidign the extra allocations, so let's render instead.
This supersedes #3874Fixes#3873
Things that tripped up a user
- Derive reference was misunderstood to say that the only alternative to
the built-in value parser behavior was to implement
`ValueParserFactory`
- We now delegate to `value_parser!`s docs any talk of integrating
into it (it should have been a subbullet of "not present" anyways)
- `value_parser!` relies too much on the example to demonstrate behavior
when the user will likely make the determination of whether its
relevant before then
- We are now more upfront what type mappings are supported
- Too many steps to find all information
- For example, a user needs to look at `TypedValueParser`
implementations, `ValueParserFactory` implementations, and `From<T>
for ValueParser` implementations to understand what all can be used
- We are now more upfront with a lot of this information at the entry
points the user is most likely to look at
In addition, I did an audit of the docs to make sure they were updated
for us only supporting the new behavior and all of the new APIs.
See https://www.reddit.com/r/rust/comments/xjlie4/preannouncing_clap_40_a_rust_cli_argument_parser/ip9kzf1/
`clap::Error::raw` was producing ambiguity errors with a default generic
parameter on `clap::error::Error` (which `clap::Error` is a re-export
of).
I tried making `clap::Error` a type alias with a default generic
parameter but that ran into an ambiguity error with `map_err`.
So I'm going ahead and hard coding `clap::Error`. We don't expect
people to change this all that often.
This takes off another 14 KiB when color us not used. My hope is that
we'll be able to switch away from `termcolor` to a term styling crate
that will make this work in the color case as well.
This is a cheap pass at creating this to allow cutting out the cost of
rich error information / programmatic error information.
This cuts about 20 KiB off of the binary.
There is more we could cut out, like collecting of used arguments for
the usage, but I want to keep the conditionals simple.
Originally, clap carried a lifetime parameter. When moving away from
that, we took the approach that dynamically generated strings are always
supported and `&'static str` was just an optimization.
The problem is the code size increase from this is dramatic. So we're
taking the opposite approach and making dynamic formatting opt-in under
the `string` feature flag. When deciding on an implementation, I
favored the faster one rather than the one with smaller code size since
small code size can be gotten through other means.
Before: 567.2 KiB, 15.975 µs
After: 541.1 KiB, 9.7855 µs
With `string`: 576.6 KiB, 13.016 µs
The overall hope is to allow a `&'static str`-only version of clap, so
we need to move off of `Str` where dynamic strings are required. We
need it here for subcommands due to external subcommands.
This had minimal impact on code size (567.2 to 567.5 KiB)
This makes us accept `str` and not do any allocations at the cost of
panicing if unsupported which I think fits our overall story in trying
to catch development-time errors.
Just having `--help` or `--version` can make us get invalid args instead
of invalid subcommands. It doesn't make sense to do this unless
positionals are used. Even then it might not make sense but this is at
least a step in the right direction.
Unsure how I feel about this being backported to clap 3. It most likely
would be fine?
This was noticed while looking into #4218
This was ported over from the usage parser which modeled after docopt.
We just never got around to implementing the rest of the syntax.
However, when considering this as a standalone feature, an
`arg!(--flag <value>)`, outside of other context, should be optional.
This is how the help would display it.
Fixes#4206
In looking at other help output, I noticed that they use two spaces, in
place of clap's 4, and it doesn't suffer from legibility. If it
doesn't make the output worse, let's go ahead and make it as dense so we
fit more content on the screen.
This is a part of #4132
If short help is too long for the terminal, clap will automatically
switch to next line help. As part of next line help for longs, we add a
blank line between args. This helps make the args clearer when dealing
with multiple paragraphs. However, its not as much needed for short and
subcommands (always short), so now short matches subcommands.
This was inspired by #3300 and a part of #4132
This makes it match up with `Command::allow_hyphen_values` which was the
guiding factor for what the behavior should be.
This supersedes #4039Fixes#3880Fixes#1538
This has been a bit out of place being on the command. Now its clearer
what the user intends to be the trailing var arg and it is more likely
to be discovered.
In reviewing CLIs for #4132, I found some were providing helps on `-h`
vs `--help` and figured that could be built directly into clap. I had
considered not making this hint automatic but I figured the overhead of
checking if long exists wouldn't be too bad. The code exists (no binary
size increase) and just a simple iteration is probably not too slow
compared to everything else.
Fixes#1015
This ensures we don't end up with accidental leading or trailing
newlines due to help template variables not being used when a section is
empty.
This is prep for removing name/version from the default template and is
part of #4132
In switching to title case for help headings (#4123), it caused me to
look at "subcommand" in a fresh light. I can't quite put my finger on
it but "Subcommand" looks a bit sloppy. I also have recently been
surveying other CLIs and they just use "command" as well.
All of them are commands anyways, just some are children of others
(subcommands) while others are not (root or top-level commands, or just
command). Context is good enough for clarifying subcommands from root
commands.
This is part of #4132
The setting was added to resolve#769. The reason it was optional is out
of concern for applications with a lot of positional arguments. I think
those cases are rare enough that we should just push people to override
the usage. Positional arguments are generally important enough, even if
optional, to show.
As a side effect, this fixed some bugs with
`dont_collapse_args_in_usage` where it would repeat an argument in a
smart usage.
As a side effect, smart usage now shows `--` when it should
This prevents global args from showing in help completions,
since help completions should only suggest subcommands.
Adds tests to ensure the args still show in the generated
help messages of subcommands.
* Copy hide flag
* Revert global args special handling. Another commit will
address the issue of whether global args should be included in
help subtrees.
In surveying various tools and CLI parsers, I noticed they list the
subcommands first. This puts an emphasis on them which makes sense
because that is most likely what an end user is supposed to pass in
next.
Listing them last aligns with the usage order but it probably doesn't
outweigh the value of getting a user moving forward.
I see them fulfilling two roles
- A form of bolding
- As a callback to their placeholder in usage
However, it is a bit of an unpolished look and no other CLI seems to do
it. This looks a bit more proefessional. We have colored help for
formatting and I think the sections relation to usage will be clear
enough.
Adds parser flags to toggle whether to run the
expensive clone logic for completions case.
Help completion will only suggest subcommands, not args.
clap_complete generator sets the flag.
The immediate benefit is binary size but this also makes us more
flexible on the implementation, like allowing wrapping of `StyledStr`.
This removed 12 KiB from `.text`
This helps towards #1365 and probably #2037
For now, there isn't much a custom implementation can do.
Going from `Rich` to `Null` drops about 6 KiB from the binary
This is a part of #1365 and #1384
This adds feature parity for mangen with the standard help output. Users
will now see the list of possible values for value arguments.
One change that was made to make this possible was adding the method
`get_possible_values` to the public API for an arg. I tried to think of
a way to get around this, but because this is the interface that the
help generation uses, and it is part of the crate public interface
I thing adding it as a part of the public API might be for the best.
fixes: #3861
The performance gains of writing directly to the writer are not worth
the complexity. Output is not in our performance hot path.
Binary size went from 565.7 KiB to 562.2 KiB
Extend Command::override_usage() doc string to describe how to format
multiple usage lines to be compatible with clap's default help formatter.
Relates-to: #3413
The binary size and performance difference is enough to make it
configurable.
Code size:
- default: 565.7 KiB
- perf: 578.5 KiB
Build time:
- default: 9.1706 us
- perf: 7.0479 us
Parse time:
- default: 12.673 us
- perf: 8.1708 us
Parse with subcommand time:
- default: 12.112 us
- perf: 7.9874 us
Another step towards #1041
This isn't the long term type for `PossibleValue::help`, I just wanted
to get the lifetime out of the way first before figuring out how help
will work.
While `TypedValueParser` will generally make it easier to reuse value
parsers, this was particularly written for flags. Besides having a
concrete API to document, an advantage over `fn(&str) -> Result<bool, E>`
value parsers is you get all of the benefits of the existing value
parsers for environment variable parsing.
The main breakinge change cases:
- `&[char]`: now requires removing `&`
- All other non-ID `&[_]`: hopefully #1041 will make these non-breaking
Fixes#2870
For now, we are focusing only on iterating over the argument ids and not
the values.
This provides a building block for more obscure use cases like iterating
over argument values, in order. We are not providing it out of the box
at the moment both to not overly incentize a less common case, because
it would abstract away a performance hit, and because we want to let
people experiment with this and if a common path emerges we can consider
it then if there is enough users.
Fixes#1206
Now that `Id` is public, we can have `ArgMatches` report them. If we
have to choose one behavior, this is more universal. The user can still
look up the values, this works with groups whose args have different
types, and this allows people to make decisions off of it when otherwise
there isn't enogh information.
Fixes#2317Fixes#3748
This is a step towards #1041
- `ArgGroup` no longer takes a lifetime
- One less field type needs a lifetime
For now, we are using a more brute force type (`String`) so we can
establish performance base lines. I was torn on whether to use `&str`
everywhere or make an `IdRef`. The latter would add a lot of noise that
I'm concerned about, so i left it simple for now. `IdRef` would help to
communicate the types involved though.
Speaking of communicating types, I'm also torn on whether we should use
`Id` for all strings or if we should have `Id`, `Name`, etc types to
avoid people mixing and matching.
This added 18.7 KB.
Compared to `HEAD~` on `06_rustup`:
- build: 6.23us -> 7.41us
- parse: 8.17us -> 9.36us
- parse_sc: 7.65us -> 9.29us
This is a part of #2870 and is prep for #1041
Oddly enough, this dropped the binary size by 200 Bytes
Compared to `HEAD~` on `06_rustup`:
- build: 6.21us -> 6.23us
- parse: 7.55us -> 8.17us
- parse_sc: 7.95us -> 7.65us
This dropped 17KB
Again, performance shouldn't be too bad as the total number of argument
id's passed in by the user shouldn't be huge, with the upper end being
5-15 except for in extreme cases like rustc accepting arguments from
cargo via a file.
This dropped `.text` by 14KB
Anything in debug asserts or help/usage output doesn't matter for
performance but I wouldn't be surprised if this was comparable since the
container sizes we are talking about are relatively small.
Documenting the existing behavior is challenging which suggests it can
cause user confusion. So long as its not too hard to explicitly
specify actions, we should just do it.
Fixes#4057
Before we introduced actions, it required specific setups to engage with
claps version and help printing. With actions making that more
explicit, we don't get as much benefit from our multiple, obscure, ways
of users customizing help
Before
- Modify existing help or version with `mut_arg` which would
automatically be pushed down the command tree like `global(true)`
- Create an new help or version and have it treated as if it was the
built-in on (I think)
- Use the same flags as built-in and have the built-in flags
automatically disabled
- Users could explicitly disable the built-in functionality and do what
they want
Now
- `mut_arg` no longer works as we define help and version flags at the
end
- If someone defines a flag that overlaps with the built-ins by id,
long, or short, a debug assert will tell them to explicitly disable
the built-in
- Any customization has to be done by a user providing their own. To
propagate through the command tree, they need to set `global(true)`.
Benefits
- Hopefully, this makes it less confusing on how to override help
behavior. Someone creates an arg and we then tell them how to disable
the built-in
- This greatly simplifies the arg handling by pushing more
responsibility onto the developer in what are hopefully just corner
cases
- This removes about 1Kb from .text
Fixes#3405Fixes#4033
Previously the Arg id was set with the "name" attribute. This allows use
of an "id" attribute to match the underlying struct.
A side effect of this is that the "id" attribute may also be used on
Commands. This isn't desired, but given the current architecture of the
attribute parser, it's hard to avoid.
Fixes: #3785
