clap/examples/14_groups.rs
Ed Page bfa02fd418 test: More thoroughly test examples
This ports our example testing over to [trycmd](https://docs.rs/) so
we can:
- More thoroughly test our examples
- Provide always-up-to-date example usage

The old way of testing automatically picked up examples.  This new way
requires we have a `.md` file that uses the example in some way.

Notes:
- Moved overall example description to the `.md` file
- I added cross-linking between related examples
- `14_groups` had a redundant paragraph (twice talked about "one and
  only one"
2021-11-23 13:13:41 -06:00

72 lines
2.4 KiB
Rust

use clap::{arg, App, Arg, ArgGroup};
fn main() {
// Create application like normal
let matches = App::new("myapp")
// Add the version arguments
.arg(arg!(--"set-ver" <ver> "set version manually").required(false))
.arg(arg!(--major "auto inc major"))
.arg(arg!(--minor "auto inc minor"))
.arg(arg!(--patch "auto inc patch"))
// Create a group, make it required, and add the above arguments
.group(
ArgGroup::new("vers")
.required(true)
.args(&["set-ver", "major", "minor", "patch"]),
)
// Arguments can also be added to a group individually, these two arguments
// are part of the "input" group which is not required
.arg(arg!([INPUT_FILE] "some regular input").group("input"))
.arg(
arg!(--"spec-in" <SPEC_IN> "some special input argument")
.required(false)
.group("input"),
)
// Now let's assume we have a -c [config] argument which requires one of
// (but **not** both) the "input" arguments
.arg(
Arg::new("config")
.short('c')
.takes_value(true)
.requires("input"),
)
.get_matches();
// Let's assume the old version 1.2.3
let mut major = 1;
let mut minor = 2;
let mut patch = 3;
// See if --set-ver was used to set the version manually
let version = if let Some(ver) = matches.value_of("set-ver") {
ver.to_string()
} else {
// Increment the one requested (in a real program, we'd reset the lower numbers)
let (maj, min, pat) = (
matches.is_present("major"),
matches.is_present("minor"),
matches.is_present("patch"),
);
match (maj, min, pat) {
(true, _, _) => major += 1,
(_, true, _) => minor += 1,
(_, _, true) => patch += 1,
_ => unreachable!(),
};
format!("{}.{}.{}", major, minor, patch)
};
println!("Version: {}", version);
// Check for usage of -c
if matches.is_present("config") {
let input = matches
.value_of("INPUT_FILE")
.unwrap_or_else(|| matches.value_of("spec-in").unwrap());
println!(
"Doing work using input {} and config {}",
input,
matches.value_of("config").unwrap()
);
}
}