use cfg_if::cfg_if;
use rand::{Rng, SeedableRng, distr::Alphanumeric, rngs::SmallRng};
use std::iter;
#[cfg(test)]
const TEST_RANDOM_SEED: [u8; 32] = [
0x53, 0x43, 0x50, 0x2d, 0x31, 0x37, 0x33, 0x3a, 0x20, 0x4d, 0x6f, 0x76, 0x65, 0x64,
0x20, 0x74, 0x6f, 0x20, 0x53, 0x69, 0x74, 0x65, 0x2d, 0x31, 0x39, 0x20, 0x31, 0x39,
0x39, 0x33, 0x2e, 0x0a,
];
#[derive(Debug)]
pub struct Random {
rng: SmallRng,
}
impl Default for Random {
#[inline]
fn default() -> Self {
cfg_if! {
if #[cfg(test)] {
let rng = SmallRng::from_seed(TEST_RANDOM_SEED);
} else {
let rng = SmallRng::from_rng(&mut rand::rng());
}
}
Random { rng }
}
}
impl Random {
pub fn generate_html_id_into(&mut self, buffer: &mut String) {
buffer.push_str("wj-id-");
let char_stream = iter::repeat(())
.map(|_| self.rng.sample(Alphanumeric))
.map(char::from)
.take(16);
buffer.extend(char_stream);
}
pub fn generate_html_id(&mut self) -> String {
let mut buffer = String::new();
self.generate_html_id_into(&mut buffer);
buffer
}
}
#[test]
fn html_id() {
let mut rand = Random::default();
let mut buffer = String::new();
rand.generate_html_id_into(&mut buffer);
assert_eq!(
buffer, "wj-id-bW5Ql2DLZtnd9s18",
"Generated HTML ID doesn't match expected",
);
let html_id = rand.generate_html_id();
assert_eq!(
html_id, "wj-id-ePZbhugrfP89c4Fk",
"Generated HTML ID doesn't match expected",
);
}