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#[cfg(feature = "yaml")]
use std::collections::BTreeMap;
use std::fmt::{Debug, Formatter, Result};
#[cfg(feature = "yaml")]
use yaml_rust::Yaml;
/// `ArgGroup`s are a family of related [arguments] and way for you to express, "Any of these
/// arguments". By placing arguments in a logical group, you can create easier requirement and
/// exclusion rules instead of having to list each argument individually, or when you want a rule
/// to apply "any but not all" arguments.
///
/// For instance, you can make an entire `ArgGroup` required. If [`ArgGroup::multiple(true)`] is
/// set, this means that at least one argument from that group must be present. If
/// [`ArgGroup::multiple(false)`] is set (the default), one and *only* one must be present.
///
/// You can also do things such as name an entire `ArgGroup` as a [conflict] or [requirement] for
/// another argument, meaning any of the arguments that belong to that group will cause a failure
/// if present, or must present respectively.
///
/// Perhaps the most common use of `ArgGroup`s is to require one and *only* one argument to be
/// present out of a given set. Imagine that you had multiple arguments, and you want one of them
/// to be required, but making all of them required isn't feasible because perhaps they conflict
/// with each other. For example, lets say that you were building an application where one could
/// set a given version number by supplying a string with an option argument, i.e.
/// `--set-ver v1.2.3`, you also wanted to support automatically using a previous version number
/// and simply incrementing one of the three numbers. So you create three flags `--major`,
/// `--minor`, and `--patch`. All of these arguments shouldn't be used at one time but you want to
/// specify that *at least one* of them is used. For this, you can create a group.
///
/// Finally, you may use `ArgGroup`s to pull a value from a group of arguments when you don't care
/// exactly which argument was actually used at runtime.
///
/// # Examples
///
/// The following example demonstrates using an `ArgGroup` to ensure that one, and only one, of
/// the arguments from the specified group is present at runtime.
///
/// ```rust
/// # use clap::{App, ArgGroup, ErrorKind};
/// let result = App::new("app")
/// .args_from_usage(
/// "--set-ver [ver] 'set the version manually'
/// --major 'auto increase major'
/// --minor 'auto increase minor'
/// --patch 'auto increase patch'")
/// .group(ArgGroup::with_name("vers")
/// .args(&["set-ver", "major", "minor", "patch"])
/// .required(true))
/// .get_matches_from_safe(vec!["app", "--major", "--patch"]);
/// // Because we used two args in the group it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::ArgumentConflict);
/// ```
/// This next example shows a passing parse of the same scenario
///
/// ```rust
/// # use clap::{App, ArgGroup};
/// let result = App::new("app")
/// .args_from_usage(
/// "--set-ver [ver] 'set the version manually'
/// --major 'auto increase major'
/// --minor 'auto increase minor'
/// --patch 'auto increase patch'")
/// .group(ArgGroup::with_name("vers")
/// .args(&["set-ver", "major", "minor","patch"])
/// .required(true))
/// .get_matches_from_safe(vec!["app", "--major"]);
/// assert!(result.is_ok());
/// let matches = result.unwrap();
/// // We may not know which of the args was used, so we can test for the group...
/// assert!(matches.is_present("vers"));
/// // we could also alternatively check each arg individually (not shown here)
/// ```
/// [`ArgGroup::multiple(true)`]: ./struct.ArgGroup.html#method.multiple
/// [arguments]: ./struct.Arg.html
/// [conflict]: ./struct.Arg.html#method.conflicts_with
/// [requirement]: ./struct.Arg.html#method.requires
#[derive(Default)]
pub struct ArgGroup<'a> {
#[doc(hidden)]
pub name: &'a str,
#[doc(hidden)]
pub args: Vec<&'a str>,
#[doc(hidden)]
pub required: bool,
#[doc(hidden)]
pub requires: Option<Vec<&'a str>>,
#[doc(hidden)]
pub conflicts: Option<Vec<&'a str>>,
#[doc(hidden)]
pub multiple: bool,
}
impl<'a> ArgGroup<'a> {
/// Creates a new instance of `ArgGroup` using a unique string name. The name will be used to
/// get values from the group or refer to the group inside of conflict and requirement rules.
///
/// # Examples
///
/// ```rust
/// # use clap::{App, ArgGroup};
/// ArgGroup::with_name("config")
/// # ;
/// ```
pub fn with_name(n: &'a str) -> Self {
ArgGroup {
name: n,
required: false,
args: vec![],
requires: None,
conflicts: None,
multiple: false,
}
}
/// Creates a new instance of `ArgGroup` from a .yml (YAML) file.
///
/// # Examples
///
/// ```ignore
/// # #[macro_use]
/// # extern crate clap;
/// # use clap::ArgGroup;
/// # fn main() {
/// let yml = load_yaml!("group.yml");
/// let ag = ArgGroup::from_yaml(yml);
/// # }
/// ```
#[cfg(feature = "yaml")]
pub fn from_yaml(y: &'a Yaml) -> ArgGroup<'a> {
ArgGroup::from(y.as_hash().unwrap())
}
/// Adds an [argument] to this group by name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .group(ArgGroup::with_name("req_flags")
/// .arg("flag")
/// .arg("color"))
/// .get_matches_from(vec!["myprog", "-f"]);
/// // maybe we don't know which of the two flags was used...
/// assert!(m.is_present("req_flags"));
/// // but we can also check individually if needed
/// assert!(m.is_present("flag"));
/// ```
/// [argument]: ./struct.Arg.html
pub fn arg(mut self, n: &'a str) -> Self {
assert!(
self.name != n,
"ArgGroup '{}' can not have same name as arg inside it",
&*self.name
);
self.args.push(n);
self
}
/// Adds multiple [arguments] to this group by name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"]))
/// .get_matches_from(vec!["myprog", "-f"]);
/// // maybe we don't know which of the two flags was used...
/// assert!(m.is_present("req_flags"));
/// // but we can also check individually if needed
/// assert!(m.is_present("flag"));
/// ```
/// [arguments]: ./struct.Arg.html
pub fn args(mut self, ns: &[&'a str]) -> Self {
for n in ns {
self = self.arg(n);
}
self
}
/// Allows more than one of the ['Arg']s in this group to be used. (Default: `false`)
///
/// # Examples
///
/// Notice in this example we use *both* the `-f` and `-c` flags which are both part of the
/// group
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup};
/// let m = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .multiple(true))
/// .get_matches_from(vec!["myprog", "-f", "-c"]);
/// // maybe we don't know which of the two flags was used...
/// assert!(m.is_present("req_flags"));
/// ```
/// In this next example, we show the default behavior (i.e. `multiple(false)) which will throw
/// an error if more than one of the args in the group was used.
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"]))
/// .get_matches_from_safe(vec!["myprog", "-f", "-c"]);
/// // Because we used both args in the group it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::ArgumentConflict);
/// ```
/// ['Arg']: ./struct.Arg.html
pub fn multiple(mut self, m: bool) -> Self {
self.multiple = m;
self
}
/// Sets the group as required or not. A required group will be displayed in the usage string
/// of the application in the format `<arg|arg2|arg3>`. A required `ArgGroup` simply states
/// that one argument from this group *must* be present at runtime (unless
/// conflicting with another argument).
///
/// **NOTE:** This setting only applies to the current [`App`] / [`SubCommand`], and not
/// globally.
///
/// **NOTE:** By default, [`ArgGroup::multiple`] is set to `false` which when combined with
/// `ArgGroup::required(true)` states, "One and *only one* arg must be used from this group.
/// Use of more than one arg is an error." Vice setting `ArgGroup::multiple(true)` which
/// states, '*At least* one arg from this group must be used. Using multiple is OK."
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .required(true))
/// .get_matches_from_safe(vec!["myprog"]);
/// // Because we didn't use any of the args in the group, it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [`App`]: ./struct.App.html
/// [`SubCommand`]: ./struct.SubCommand.html
/// [`ArgGroup::multiple`]: ./struct.ArgGroup.html#method.multiple
pub fn required(mut self, r: bool) -> Self {
self.required = r;
self
}
/// Sets the requirement rules of this group. This is not to be confused with a
/// [required group]. Requirement rules function just like [argument requirement rules], you
/// can name other arguments or groups that must be present when any one of the arguments from
/// this group is used.
///
/// **NOTE:** The name provided may be an argument, or group name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .requires("debug"))
/// .get_matches_from_safe(vec!["myprog", "-c"]);
/// // because we used an arg from the group, and the group requires "-d" to be used, it's an
/// // error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [required group]: ./struct.ArgGroup.html#method.required
/// [argument requirement rules]: ./struct.Arg.html#method.requires
pub fn requires(mut self, n: &'a str) -> Self {
if let Some(ref mut reqs) = self.requires {
reqs.push(n);
} else {
self.requires = Some(vec![n]);
}
self
}
/// Sets the requirement rules of this group. This is not to be confused with a
/// [required group]. Requirement rules function just like [argument requirement rules], you
/// can name other arguments or groups that must be present when one of the arguments from this
/// group is used.
///
/// **NOTE:** The names provided may be an argument, or group name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .arg(Arg::with_name("verb")
/// .short("v"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .requires_all(&["debug", "verb"]))
/// .get_matches_from_safe(vec!["myprog", "-c", "-d"]);
/// // because we used an arg from the group, and the group requires "-d" and "-v" to be used,
/// // yet we only used "-d" it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::MissingRequiredArgument);
/// ```
/// [required group]: ./struct.ArgGroup.html#method.required
/// [argument requirement rules]: ./struct.Arg.html#method.requires_all
pub fn requires_all(mut self, ns: &[&'a str]) -> Self {
for n in ns {
self = self.requires(n);
}
self
}
/// Sets the exclusion rules of this group. Exclusion (aka conflict) rules function just like
/// [argument exclusion rules], you can name other arguments or groups that must *not* be
/// present when one of the arguments from this group are used.
///
/// **NOTE:** The name provided may be an argument, or group name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .conflicts_with("debug"))
/// .get_matches_from_safe(vec!["myprog", "-c", "-d"]);
/// // because we used an arg from the group, and the group conflicts with "-d", it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::ArgumentConflict);
/// ```
/// [argument exclusion rules]: ./struct.Arg.html#method.conflicts_with
pub fn conflicts_with(mut self, n: &'a str) -> Self {
if let Some(ref mut confs) = self.conflicts {
confs.push(n);
} else {
self.conflicts = Some(vec![n]);
}
self
}
/// Sets the exclusion rules of this group. Exclusion rules function just like
/// [argument exclusion rules], you can name other arguments or groups that must *not* be
/// present when one of the arguments from this group are used.
///
/// **NOTE:** The names provided may be an argument, or group name
///
/// # Examples
///
/// ```rust
/// # use clap::{App, Arg, ArgGroup, ErrorKind};
/// let result = App::new("myprog")
/// .arg(Arg::with_name("flag")
/// .short("f"))
/// .arg(Arg::with_name("color")
/// .short("c"))
/// .arg(Arg::with_name("debug")
/// .short("d"))
/// .arg(Arg::with_name("verb")
/// .short("v"))
/// .group(ArgGroup::with_name("req_flags")
/// .args(&["flag", "color"])
/// .conflicts_with_all(&["debug", "verb"]))
/// .get_matches_from_safe(vec!["myprog", "-c", "-v"]);
/// // because we used an arg from the group, and the group conflicts with either "-v" or "-d"
/// // it's an error
/// assert!(result.is_err());
/// let err = result.unwrap_err();
/// assert_eq!(err.kind, ErrorKind::ArgumentConflict);
/// ```
/// [argument exclusion rules]: ./struct.Arg.html#method.conflicts_with_all
pub fn conflicts_with_all(mut self, ns: &[&'a str]) -> Self {
for n in ns {
self = self.conflicts_with(n);
}
self
}
}
impl<'a> Debug for ArgGroup<'a> {
fn fmt(&self, f: &mut Formatter) -> Result {
write!(
f,
"{{\n\
\tname: {:?},\n\
\targs: {:?},\n\
\trequired: {:?},\n\
\trequires: {:?},\n\
\tconflicts: {:?},\n\
}}",
self.name, self.args, self.required, self.requires, self.conflicts
)
}
}
impl<'a, 'z> From<&'z ArgGroup<'a>> for ArgGroup<'a> {
fn from(g: &'z ArgGroup<'a>) -> Self {
ArgGroup {
name: g.name,
required: g.required,
args: g.args.clone(),
requires: g.requires.clone(),
conflicts: g.conflicts.clone(),
multiple: g.multiple,
}
}
}
#[cfg(feature = "yaml")]
impl<'a> From<&'a BTreeMap<Yaml, Yaml>> for ArgGroup<'a> {
fn from(b: &'a BTreeMap<Yaml, Yaml>) -> Self {
// We WANT this to panic on error...so expect() is good.
let mut a = ArgGroup::default();
let group_settings = if b.len() == 1 {
let name_yml = b.keys().nth(0).expect("failed to get name");
let name_str = name_yml
.as_str()
.expect("failed to convert arg YAML name to str");
a.name = name_str;
b.get(name_yml)
.expect("failed to get name_str")
.as_hash()
.expect("failed to convert to a hash")
} else {
b
};
for (k, v) in group_settings {
a = match k.as_str().unwrap() {
"required" => a.required(v.as_bool().unwrap()),
"multiple" => a.multiple(v.as_bool().unwrap()),
"args" => yaml_vec_or_str!(v, a, arg),
"arg" => {
if let Some(ys) = v.as_str() {
a = a.arg(ys);
}
a
}
"requires" => yaml_vec_or_str!(v, a, requires),
"conflicts_with" => yaml_vec_or_str!(v, a, conflicts_with),
"name" => {
if let Some(ys) = v.as_str() {
a.name = ys;
}
a
}
s => panic!(
"Unknown ArgGroup setting '{}' in YAML file for \
ArgGroup '{}'",
s, a.name
),
}
}
a
}
}
#[cfg(test)]
mod test {
use super::ArgGroup;
#[cfg(feature = "yaml")]
use yaml_rust::YamlLoader;
#[test]
fn groups() {
let g = ArgGroup::with_name("test")
.arg("a1")
.arg("a4")
.args(&["a2", "a3"])
.required(true)
.conflicts_with("c1")
.conflicts_with_all(&["c2", "c3"])
.conflicts_with("c4")
.requires("r1")
.requires_all(&["r2", "r3"])
.requires("r4");
let args = vec!["a1", "a4", "a2", "a3"];
let reqs = vec!["r1", "r2", "r3", "r4"];
let confs = vec!["c1", "c2", "c3", "c4"];
assert_eq!(g.args, args);
assert_eq!(g.requires, Some(reqs));
assert_eq!(g.conflicts, Some(confs));
}
#[test]
fn test_debug() {
let g = ArgGroup::with_name("test")
.arg("a1")
.arg("a4")
.args(&["a2", "a3"])
.required(true)
.conflicts_with("c1")
.conflicts_with_all(&["c2", "c3"])
.conflicts_with("c4")
.requires("r1")
.requires_all(&["r2", "r3"])
.requires("r4");
let args = vec!["a1", "a4", "a2", "a3"];
let reqs = vec!["r1", "r2", "r3", "r4"];
let confs = vec!["c1", "c2", "c3", "c4"];
let debug_str = format!(
"{{\n\
\tname: \"test\",\n\
\targs: {:?},\n\
\trequired: {:?},\n\
\trequires: {:?},\n\
\tconflicts: {:?},\n\
}}",
args,
true,
Some(reqs),
Some(confs)
);
assert_eq!(&*format!("{:?}", g), &*debug_str);
}
#[test]
fn test_from() {
let g = ArgGroup::with_name("test")
.arg("a1")
.arg("a4")
.args(&["a2", "a3"])
.required(true)
.conflicts_with("c1")
.conflicts_with_all(&["c2", "c3"])
.conflicts_with("c4")
.requires("r1")
.requires_all(&["r2", "r3"])
.requires("r4");
let args = vec!["a1", "a4", "a2", "a3"];
let reqs = vec!["r1", "r2", "r3", "r4"];
let confs = vec!["c1", "c2", "c3", "c4"];
let g2 = ArgGroup::from(&g);
assert_eq!(g2.args, args);
assert_eq!(g2.requires, Some(reqs));
assert_eq!(g2.conflicts, Some(confs));
}
#[cfg(feature = "yaml")]
#[cfg_attr(feature = "yaml", test)]
fn test_yaml() {
let g_yaml = "name: test
args:
- a1
- a4
- a2
- a3
conflicts_with:
- c1
- c2
- c3
- c4
requires:
- r1
- r2
- r3
- r4";
let yml = &YamlLoader::load_from_str(g_yaml).expect("failed to load YAML file")[0];
let g = ArgGroup::from_yaml(yml);
let args = vec!["a1", "a4", "a2", "a3"];
let reqs = vec!["r1", "r2", "r3", "r4"];
let confs = vec!["c1", "c2", "c3", "c4"];
assert_eq!(g.args, args);
assert_eq!(g.requires, Some(reqs));
assert_eq!(g.conflicts, Some(confs));
}
}
impl<'a> Clone for ArgGroup<'a> {
fn clone(&self) -> Self {
ArgGroup {
name: self.name,
required: self.required,
args: self.args.clone(),
requires: self.requires.clone(),
conflicts: self.conflicts.clone(),
multiple: self.multiple,
}
}
}