#[macro_use] extern crate clap; #[macro_use] extern crate clap_derive; use clap::{App, Arg}; #[derive(ArgEnum, Debug, PartialEq)] #[case_sensitive] enum ArgChoice { Foo, Bar, Baz, } #[test] fn when_lowercase() { let matches = App::new(env!("CARGO_PKG_NAME")) .arg(Arg::with_name("arg") .required(true) .takes_value(true) .possible_values(&ArgChoice::variants()) ).get_matches_from_safe(vec![ "", "foo", ]); // We expect this to fail. assert!(matches.is_err()); assert_eq!(matches.unwrap_err().kind, clap::ErrorKind::InvalidValue); } #[test] fn when_capitalized() { let matches = App::new(env!("CARGO_PKG_NAME")) .arg(Arg::with_name("arg") .required(true) .takes_value(true) .possible_values(&ArgChoice::variants()) ).get_matches_from_safe(vec![ "", "Foo", ]).unwrap(); let t = value_t!(matches.value_of("arg"), ArgChoice); assert!(t.is_ok()); assert_eq!(t.unwrap(), ArgChoice::Foo); }