A plugin for validating some selected cryptocurrency wallet address using regular expressions (regex). Note: TDD approach used

get_bitcoin_address.rs

#[macro_use]
extern crate lazy_static;

use regex::{Captures, Regex};

// starts with "1" or "3" or "bc1"
// doesn’t contain ambiguous characters
// consists of uppercase or lowercase alphabetic and numeric characters
// except the uppercase letter "O", uppercase letter "I", lowercase letter "l", and the number "0"
// check that the string is 26-35 characters long
const BITCOIN_REG_EX: &str = r"([13]|bc1)[A-HJ-NP-Za-km-z1-9]{27,34}";

fn main() {}

fn get_bitcoin_address(address: &str) -> Option<Captures> {
    // use lazy-static crate for memoization since re-compiling RegEx are expensive
    // https://crates.io/crates/lazy_static
    lazy_static! {
        static ref REGEX: Regex = Regex::new(BITCOIN_REG_EX).unwrap();
    }

    if REGEX.is_match(address) == false {
        return None;
    }

    // return regex match groups
    Some(REGEX.captures(address).unwrap())
}

#[cfg(test)]
mod test {
    use super::*;

    #[test]
    fn it_should_be_valid_bitcoin_wallet_address() {
        let addresses = vec![
            get_bitcoin_address("3J78t1WpEZ73CNmQviecrnyiWrnqRhWKXc"),
            get_bitcoin_address("1dice8EMZmqKvrGE4Qc9bUFf9PX3xaYDp"),
        ];

        assert!(!addresses[0].is_none());
        assert!(!addresses[1].is_none());
    }

    #[test]
    fn it_should_be_invalid_bitcoin_wallet_address() {
        let address = get_bitcoin_address("bc1nxr1srrr0xfkvy5r643hydnw9re59gtzzwf5pzr");

        assert!(address.is_none());
    }
}