Simple command line parser with clap

main.rs

use clap::Parser;
use regex::Regex;
use std::{
    fmt::{self, Debug, Display},
    str::FromStr,
};
use thiserror::Error;

#[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
enum Browser {
    #[default]
    Chrome,
    Firefox,
    Edge,
}

#[derive(Debug, Error)]
#[error("Unknown browser")]
struct UnknownBrowser;

impl FromStr for Browser {
    type Err = UnknownBrowser;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        match s.to_lowercase().as_str() {
            "chrome" => Ok(Browser::Chrome),
            "firefox" => Ok(Browser::Firefox),
            "edge" => Ok(Browser::Edge),
            _ => Err(UnknownBrowser),
        }
    }
}

impl Display for Browser {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Chrome => write!(f, "Chrome"),
            Self::Firefox => write!(f, "Firefox"),
            Self::Edge => write!(f, "Edge"),
        }
    }
}

/// Simple command-line argument parser
#[derive(Parser, Debug)]
#[command(version, about, long_about = None)]
struct Args {
    /// Name of the environment (and associated properties)
    #[arg(short, long, default_value = "v2.0")]
    env: String,

    /// Test suite to execute in src/test/resources/testsuites
    #[arg(short, long)]
    xml: Option<String>,

    /// Browser to use for testing
    #[arg(short, long, default_value_t)]
    browser: Browser,

    /// Selenium WebDriverWait value in seconds
    #[arg(short, long, default_value_t = 10)]
    wait: u8,

    /// Regex pattern for test cases to execute with maven failsafe plugin
    #[arg(short, long, default_value = ".*")]
    tests: Regex,
}

// cargo run -- --browser=Firefox --env=v1.0 --wait=30 --xml=smoke.xml
fn main() {
    let args = Args::parse();

    println!("Environment: {}", args.env);
    println!("Test suite: {:?}", args.xml);
    println!("Browser: {:?}", args.browser);
    println!("Selenium WebDriverWait: {} seconds", args.wait);
    println!("Regex pattern for test cases: {:?}", args.tests);
}