use clap::{error::ErrorKind, Arg, ArgAction, Command}; static HELP: &str = "\ Usage: prog [OPTIONS] Options: -a -b -c -h, --help Print help "; fn cmd() -> Command { Command::new("prog") .arg( Arg::new("a") .short('a') .action(ArgAction::SetTrue) .required_unless_present_any(["b", "c"]) .conflicts_with_all(["b", "c"]), ) .arg( Arg::new("b") .short('b') .action(ArgAction::SetTrue) .required_unless_present("a") .requires("c"), ) .arg( Arg::new("c") .short('c') .action(ArgAction::SetTrue) .required_unless_present("a") .requires("b"), ) } #[test] fn valid_cases() { let res = cmd().try_get_matches_from(vec!["", "-a"]); assert!(res.is_ok(), "{}", res.unwrap_err()); let res = cmd().clone().try_get_matches_from(vec!["", "-b", "-c"]); assert!(res.is_ok(), "{}", res.unwrap_err()); let res = cmd().try_get_matches_from(vec!["", "-c", "-b"]); assert!(res.is_ok(), "{}", res.unwrap_err()); } #[test] fn help_text() { let res = cmd().try_get_matches_from(vec!["prog", "--help"]); assert!(res.is_err()); let err = res.unwrap_err(); assert_eq!(err.kind(), ErrorKind::DisplayHelp); println!("{err}"); assert_eq!(err.to_string(), HELP); } #[test] #[cfg(feature = "error-context")] fn no_duplicate_error() { static ONLY_B_ERROR: &str = "\ error: the following required arguments were not provided: -c Usage: prog -b -c For more information, try '--help'. "; let res = cmd().try_get_matches_from(vec!["", "-b"]); assert!(res.is_err()); let err = res.unwrap_err(); assert_eq!(err.kind(), ErrorKind::MissingRequiredArgument); assert_eq!(err.to_string(), ONLY_B_ERROR); static ONLY_C_ERROR: &str = "\ error: the following required arguments were not provided: -b Usage: prog -c -b For more information, try '--help'. "; let res = cmd().try_get_matches_from(vec!["", "-c"]); assert!(res.is_err()); let err = res.unwrap_err(); assert_eq!(err.kind(), ErrorKind::MissingRequiredArgument); assert_eq!(err.to_string(), ONLY_C_ERROR); }