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use crate::Uuid;
impl Uuid {
/// Creates a random UUID.
///
/// This uses the [`getrandom`] crate to utilise the operating system's RNG
/// as the source of random numbers. If you'd like to use a custom
/// generator, don't use this method: generate random bytes using your
/// custom generator and pass them to the
/// [`uuid::Builder::from_random_bytes`][from_random_bytes] function
/// instead.
///
/// Note that usage of this method requires the `v4` feature of this crate
/// to be enabled.
///
/// # Examples
///
/// Basic usage:
///
/// ```
/// # use uuid::{Uuid, Version};
/// let uuid = Uuid::new_v4();
///
/// assert_eq!(Some(Version::Random), uuid.get_version());
/// ```
///
/// # References
///
/// * [UUID Version 4 in RFC 9562](https://www.ietf.org/rfc/rfc9562.html#section-5.4)
///
/// [`getrandom`]: https://crates.io/crates/getrandom
/// [from_random_bytes]: struct.Builder.html#method.from_random_bytes
pub fn new_v4() -> Uuid {
// This is an optimized method for generating random UUIDs that just masks
// out the bits for the version and variant and sets them both together
Uuid::from_u128(
crate::rng::u128() & 0xFFFFFFFFFFFF4FFFBFFFFFFFFFFFFFFF | 0x40008000000000000000,
)
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::{Variant, Version};
#[cfg(all(
target_arch = "wasm32",
target_vendor = "unknown",
target_os = "unknown"
))]
use wasm_bindgen_test::*;
#[test]
#[cfg_attr(
all(
target_arch = "wasm32",
target_vendor = "unknown",
target_os = "unknown"
),
wasm_bindgen_test
)]
fn test_new() {
let uuid = Uuid::new_v4();
assert_eq!(uuid.get_version(), Some(Version::Random));
assert_eq!(uuid.get_variant(), Variant::RFC4122);
}
#[test]
#[cfg_attr(
all(
target_arch = "wasm32",
target_vendor = "unknown",
target_os = "unknown"
),
wasm_bindgen_test
)]
fn test_get_version() {
let uuid = Uuid::new_v4();
assert_eq!(uuid.get_version(), Some(Version::Random));
assert_eq!(uuid.get_version_num(), 4)
}
}