Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

2 files changed, 910 insertions, 0 deletions

diff --git a/vendor/fastrand/src/global_rng.rs b/vendor/fastrand/src/global_rng.rs
new file mode 100644
index 0000000..f994902
--- /dev/null
+++ b/vendor/fastrand/src/global_rng.rs
@@ -0,0 +1,218 @@
+//! A global, thread-local random number generator.
+
+use crate::Rng;
+
+use std::cell::Cell;
+use std::ops::RangeBounds;
+
+// Chosen by fair roll of the dice.
+const DEFAULT_RNG_SEED: u64 = 0xef6f79ed30ba75a;
+
+impl Default for Rng {
+    /// Initialize the `Rng` from the system's random number generator.
+    ///
+    /// This is equivalent to [`Rng::new()`].
+    #[inline]
+    fn default() -> Rng {
+        Rng::new()
+    }
+}
+
+impl Rng {
+    /// Creates a new random number generator.
+    #[inline]
+    pub fn new() -> Rng {
+        try_with_rng(Rng::fork).unwrap_or_else(|_| Rng::with_seed(0x4d595df4d0f33173))
+    }
+}
+
+thread_local! {
+    static RNG: Cell<Rng> = Cell::new(Rng(random_seed().unwrap_or(DEFAULT_RNG_SEED)));
+}
+
+/// Run an operation with the current thread-local generator.
+#[inline]
+fn with_rng<R>(f: impl FnOnce(&mut Rng) -> R) -> R {
+    RNG.with(|rng| {
+        let current = rng.replace(Rng(0));
+
+        let mut restore = RestoreOnDrop { rng, current };
+
+        f(&mut restore.current)
+    })
+}
+
+/// Try to run an operation with the current thread-local generator.
+#[inline]
+fn try_with_rng<R>(f: impl FnOnce(&mut Rng) -> R) -> Result<R, std::thread::AccessError> {
+    RNG.try_with(|rng| {
+        let current = rng.replace(Rng(0));
+
+        let mut restore = RestoreOnDrop { rng, current };
+
+        f(&mut restore.current)
+    })
+}
+
+/// Make sure the original RNG is restored even on panic.
+struct RestoreOnDrop<'a> {
+    rng: &'a Cell<Rng>,
+    current: Rng,
+}
+
+impl Drop for RestoreOnDrop<'_> {
+    fn drop(&mut self) {
+        self.rng.set(Rng(self.current.0));
+    }
+}
+
+/// Initializes the thread-local generator with the given seed.
+#[inline]
+pub fn seed(seed: u64) {
+    with_rng(|r| r.seed(seed));
+}
+
+/// Gives back **current** seed that is being held by the thread-local generator.
+#[inline]
+pub fn get_seed() -> u64 {
+    with_rng(|r| r.get_seed())
+}
+
+/// Generates a random `bool`.
+#[inline]
+pub fn bool() -> bool {
+    with_rng(|r| r.bool())
+}
+
+/// Generates a random `char` in ranges a-z and A-Z.
+#[inline]
+pub fn alphabetic() -> char {
+    with_rng(|r| r.alphabetic())
+}
+
+/// Generates a random `char` in ranges a-z, A-Z and 0-9.
+#[inline]
+pub fn alphanumeric() -> char {
+    with_rng(|r| r.alphanumeric())
+}
+
+/// Generates a random `char` in range a-z.
+#[inline]
+pub fn lowercase() -> char {
+    with_rng(|r| r.lowercase())
+}
+
+/// Generates a random `char` in range A-Z.
+#[inline]
+pub fn uppercase() -> char {
+    with_rng(|r| r.uppercase())
+}
+
+/// Choose an item from an iterator at random.
+///
+/// This function may have an unexpected result if the `len()` property of the
+/// iterator does not match the actual number of items in the iterator. If
+/// the iterator is empty, this returns `None`.
+#[inline]
+pub fn choice<I>(iter: I) -> Option<I::Item>
+where
+    I: IntoIterator,
+    I::IntoIter: ExactSizeIterator,
+{
+    with_rng(|r| r.choice(iter))
+}
+
+/// Generates a random digit in the given `base`.
+///
+/// Digits are represented by `char`s in ranges 0-9 and a-z.
+///
+/// Panics if the base is zero or greater than 36.
+#[inline]
+pub fn digit(base: u32) -> char {
+    with_rng(|r| r.digit(base))
+}
+
+/// Shuffles a slice randomly.
+#[inline]
+pub fn shuffle<T>(slice: &mut [T]) {
+    with_rng(|r| r.shuffle(slice))
+}
+
+macro_rules! integer {
+    ($t:tt, $doc:tt) => {
+        #[doc = $doc]
+        ///
+        /// Panics if the range is empty.
+        #[inline]
+        pub fn $t(range: impl RangeBounds<$t>) -> $t {
+            with_rng(|r| r.$t(range))
+        }
+    };
+}
+
+integer!(u8, "Generates a random `u8` in the given range.");
+integer!(i8, "Generates a random `i8` in the given range.");
+integer!(u16, "Generates a random `u16` in the given range.");
+integer!(i16, "Generates a random `i16` in the given range.");
+integer!(u32, "Generates a random `u32` in the given range.");
+integer!(i32, "Generates a random `i32` in the given range.");
+integer!(u64, "Generates a random `u64` in the given range.");
+integer!(i64, "Generates a random `i64` in the given range.");
+integer!(u128, "Generates a random `u128` in the given range.");
+integer!(i128, "Generates a random `i128` in the given range.");
+integer!(usize, "Generates a random `usize` in the given range.");
+integer!(isize, "Generates a random `isize` in the given range.");
+integer!(char, "Generates a random `char` in the given range.");
+
+/// Generates a random `f32` in range `0..1`.
+pub fn f32() -> f32 {
+    with_rng(|r| r.f32())
+}
+
+/// Generates a random `f64` in range `0..1`.
+pub fn f64() -> f64 {
+    with_rng(|r| r.f64())
+}
+
+/// Collects `amount` values at random from the iterator into a vector.
+pub fn choose_multiple<T: Iterator>(source: T, amount: usize) -> Vec<T::Item> {
+    with_rng(|rng| rng.choose_multiple(source, amount))
+}
+
+#[cfg(not(all(
+    any(target_arch = "wasm32", target_arch = "wasm64"),
+    target_os = "unknown"
+)))]
+fn random_seed() -> Option<u64> {
+    use std::collections::hash_map::DefaultHasher;
+    use std::hash::{Hash, Hasher};
+    use std::thread;
+    use std::time::Instant;
+
+    let mut hasher = DefaultHasher::new();
+    Instant::now().hash(&mut hasher);
+    thread::current().id().hash(&mut hasher);
+    let hash = hasher.finish();
+    Some((hash << 1) | 1)
+}
+
+#[cfg(all(
+    any(target_arch = "wasm32", target_arch = "wasm64"),
+    target_os = "unknown",
+    feature = "js"
+))]
+fn random_seed() -> Option<u64> {
+    // TODO(notgull): Failures should be logged somewhere.
+    let mut seed = [0u8; 8];
+    getrandom::getrandom(&mut seed).ok()?;
+    Some(u64::from_ne_bytes(seed))
+}
+
+#[cfg(all(
+    any(target_arch = "wasm32", target_arch = "wasm64"),
+    target_os = "unknown",
+    not(feature = "js")
+))]
+fn random_seed() -> Option<u64> {
+    None
+}
diff --git a/vendor/fastrand/src/lib.rs b/vendor/fastrand/src/lib.rs
new file mode 100644
index 0000000..24de8dd
--- /dev/null
+++ b/vendor/fastrand/src/lib.rs
@@ -0,0 +1,692 @@
+//! A simple and fast random number generator.
+//!
+//! The implementation uses [Wyrand](https://github.com/wangyi-fudan/wyhash), a simple and fast
+//! generator but **not** cryptographically secure.
+//!
+//! # Examples
+//!
+//! Flip a coin:
+//!
+//! ```
+//! if fastrand::bool() {
+//!     println!("heads");
+//! } else {
+//!     println!("tails");
+//! }
+//! ```
+//!
+//! Generate a random `i32`:
+//!
+//! ```
+//! let num = fastrand::i32(..);
+//! ```
+//!
+//! Choose a random element in an array:
+//!
+//! ```
+//! let v = vec![1, 2, 3, 4, 5];
+//! let i = fastrand::usize(..v.len());
+//! let elem = v[i];
+//! ```
+//!
+//! Sample values from an array with `O(n)` complexity (`n` is the length of array):
+//!
+//! ```
+//! fastrand::choose_multiple(vec![1, 4, 5].iter(), 2);
+//! fastrand::choose_multiple(0..20, 12);
+//! ```
+//!
+//!
+//! Shuffle an array:
+//!
+//! ```
+//! let mut v = vec![1, 2, 3, 4, 5];
+//! fastrand::shuffle(&mut v);
+//! ```
+//!
+//! Generate a random [`Vec`] or [`String`]:
+//!
+//! ```
+//! use std::iter::repeat_with;
+//!
+//! let v: Vec<i32> = repeat_with(|| fastrand::i32(..)).take(10).collect();
+//! let s: String = repeat_with(fastrand::alphanumeric).take(10).collect();
+//! ```
+//!
+//! To get reproducible results on every run, initialize the generator with a seed:
+//!
+//! ```
+//! // Pick an arbitrary number as seed.
+//! fastrand::seed(7);
+//!
+//! // Now this prints the same number on every run:
+//! println!("{}", fastrand::u32(..));
+//! ```
+//!
+//! To be more efficient, create a new [`Rng`] instance instead of using the thread-local
+//! generator:
+//!
+//! ```
+//! use std::iter::repeat_with;
+//!
+//! let mut rng = fastrand::Rng::new();
+//! let mut bytes: Vec<u8> = repeat_with(|| rng.u8(..)).take(10_000).collect();
+//! ```
+//!
+//! This crate aims to expose a core set of useful randomness primitives. For more niche algorithms,
+//! consider using the [`fastrand-contrib`] crate alongside this one.
+//!
+//! # Features
+//!
+//! - `std` (enabled by default): Enables the `std` library. This is required for the global
+//!   generator and global entropy. Without this feature, [`Rng`] can only be instantiated using
+//!   the [`with_seed`](Rng::with_seed) method.
+//! - `js`: Assumes that WebAssembly targets are being run in a JavaScript environment. See the
+//!   [WebAssembly Notes](#webassembly-notes) section for more information.
+//!
+//! # WebAssembly Notes
+//!
+//! For non-WASI WASM targets, there is additional sublety to consider when utilizing the global RNG.
+//! By default, `std` targets will use entropy sources in the standard library to seed the global RNG.
+//! However, these sources are not available by default on WASM targets outside of WASI.
+//!
+//! If the `js` feature is enabled, this crate will assume that it is running in a JavaScript
+//! environment. At this point, the [`getrandom`] crate will be used in order to access the available
+//! entropy sources and seed the global RNG. If the `js` feature is not enabled, the global RNG will
+//! use a predefined seed.
+//!
+//! [`fastrand-contrib`]: https://crates.io/crates/fastrand-contrib
+//! [`getrandom`]: https://crates.io/crates/getrandom
+
+#![cfg_attr(not(feature = "std"), no_std)]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![forbid(unsafe_code)]
+#![warn(missing_docs, missing_debug_implementations, rust_2018_idioms)]
+#![doc(
+    html_favicon_url = "https://raw.githubusercontent.com/smol-rs/smol/master/assets/images/logo_fullsize_transparent.png"
+)]
+#![doc(
+    html_logo_url = "https://raw.githubusercontent.com/smol-rs/smol/master/assets/images/logo_fullsize_transparent.png"
+)]
+
+#[cfg(feature = "alloc")]
+extern crate alloc;
+
+use core::convert::{TryFrom, TryInto};
+use core::ops::{Bound, RangeBounds};
+
+#[cfg(feature = "alloc")]
+use alloc::vec::Vec;
+
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
+mod global_rng;
+
+#[cfg(feature = "std")]
+pub use global_rng::*;
+
+/// A random number generator.
+#[derive(Debug, PartialEq, Eq)]
+pub struct Rng(u64);
+
+impl Clone for Rng {
+    /// Clones the generator by creating a new generator with the same seed.
+    fn clone(&self) -> Rng {
+        Rng::with_seed(self.0)
+    }
+}
+
+impl Rng {
+    /// Generates a random `u32`.
+    #[inline]
+    fn gen_u32(&mut self) -> u32 {
+        self.gen_u64() as u32
+    }
+
+    /// Generates a random `u64`.
+    #[inline]
+    fn gen_u64(&mut self) -> u64 {
+        let s = self.0.wrapping_add(0xA0761D6478BD642F);
+        self.0 = s;
+        let t = u128::from(s) * u128::from(s ^ 0xE7037ED1A0B428DB);
+        (t as u64) ^ (t >> 64) as u64
+    }
+
+    /// Generates a random `u128`.
+    #[inline]
+    fn gen_u128(&mut self) -> u128 {
+        (u128::from(self.gen_u64()) << 64) | u128::from(self.gen_u64())
+    }
+
+    /// Generates a random `u32` in `0..n`.
+    #[inline]
+    fn gen_mod_u32(&mut self, n: u32) -> u32 {
+        // Adapted from: https://lemire.me/blog/2016/06/30/fast-random-shuffling/
+        let mut r = self.gen_u32();
+        let mut hi = mul_high_u32(r, n);
+        let mut lo = r.wrapping_mul(n);
+        if lo < n {
+            let t = n.wrapping_neg() % n;
+            while lo < t {
+                r = self.gen_u32();
+                hi = mul_high_u32(r, n);
+                lo = r.wrapping_mul(n);
+            }
+        }
+        hi
+    }
+
+    /// Generates a random `u64` in `0..n`.
+    #[inline]
+    fn gen_mod_u64(&mut self, n: u64) -> u64 {
+        // Adapted from: https://lemire.me/blog/2016/06/30/fast-random-shuffling/
+        let mut r = self.gen_u64();
+        let mut hi = mul_high_u64(r, n);
+        let mut lo = r.wrapping_mul(n);
+        if lo < n {
+            let t = n.wrapping_neg() % n;
+            while lo < t {
+                r = self.gen_u64();
+                hi = mul_high_u64(r, n);
+                lo = r.wrapping_mul(n);
+            }
+        }
+        hi
+    }
+
+    /// Generates a random `u128` in `0..n`.
+    #[inline]
+    fn gen_mod_u128(&mut self, n: u128) -> u128 {
+        // Adapted from: https://lemire.me/blog/2016/06/30/fast-random-shuffling/
+        let mut r = self.gen_u128();
+        let mut hi = mul_high_u128(r, n);
+        let mut lo = r.wrapping_mul(n);
+        if lo < n {
+            let t = n.wrapping_neg() % n;
+            while lo < t {
+                r = self.gen_u128();
+                hi = mul_high_u128(r, n);
+                lo = r.wrapping_mul(n);
+            }
+        }
+        hi
+    }
+}
+
+/// Computes `(a * b) >> 32`.
+#[inline]
+fn mul_high_u32(a: u32, b: u32) -> u32 {
+    (((a as u64) * (b as u64)) >> 32) as u32
+}
+
+/// Computes `(a * b) >> 64`.
+#[inline]
+fn mul_high_u64(a: u64, b: u64) -> u64 {
+    (((a as u128) * (b as u128)) >> 64) as u64
+}
+
+/// Computes `(a * b) >> 128`.
+#[inline]
+fn mul_high_u128(a: u128, b: u128) -> u128 {
+    // Adapted from: https://stackoverflow.com/a/28904636
+    let a_lo = a as u64 as u128;
+    let a_hi = (a >> 64) as u64 as u128;
+    let b_lo = b as u64 as u128;
+    let b_hi = (b >> 64) as u64 as u128;
+    let carry = (a_lo * b_lo) >> 64;
+    let carry = ((a_hi * b_lo) as u64 as u128 + (a_lo * b_hi) as u64 as u128 + carry) >> 64;
+    a_hi * b_hi + ((a_hi * b_lo) >> 64) + ((a_lo * b_hi) >> 64) + carry
+}
+
+macro_rules! rng_integer {
+    ($t:tt, $unsigned_t:tt, $gen:tt, $mod:tt, $doc:tt) => {
+        #[doc = $doc]
+        ///
+        /// Panics if the range is empty.
+        #[inline]
+        pub fn $t(&mut self, range: impl RangeBounds<$t>) -> $t {
+            let panic_empty_range = || {
+                panic!(
+                    "empty range: {:?}..{:?}",
+                    range.start_bound(),
+                    range.end_bound()
+                )
+            };
+
+            let low = match range.start_bound() {
+                Bound::Unbounded => core::$t::MIN,
+                Bound::Included(&x) => x,
+                Bound::Excluded(&x) => x.checked_add(1).unwrap_or_else(panic_empty_range),
+            };
+
+            let high = match range.end_bound() {
+                Bound::Unbounded => core::$t::MAX,
+                Bound::Included(&x) => x,
+                Bound::Excluded(&x) => x.checked_sub(1).unwrap_or_else(panic_empty_range),
+            };
+
+            if low > high {
+                panic_empty_range();
+            }
+
+            if low == core::$t::MIN && high == core::$t::MAX {
+                self.$gen() as $t
+            } else {
+                let len = high.wrapping_sub(low).wrapping_add(1);
+                low.wrapping_add(self.$mod(len as $unsigned_t as _) as $t)
+            }
+        }
+    };
+}
+
+impl Rng {
+    /// Creates a new random number generator with the initial seed.
+    #[inline]
+    #[must_use = "this creates a new instance of `Rng`; if you want to initialize the thread-local generator, use `fastrand::seed()` instead"]
+    pub fn with_seed(seed: u64) -> Self {
+        let mut rng = Rng(0);
+
+        rng.seed(seed);
+        rng
+    }
+
+    /// Clones the generator by deterministically deriving a new generator based on the initial
+    /// seed.
+    ///
+    /// This function can be used to create a new generator that is a "spinoff" of the old
+    /// generator. The new generator will not produce the same sequence of values as the
+    /// old generator.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// // Seed two generators equally, and clone both of them.
+    /// let mut base1 = fastrand::Rng::with_seed(0x4d595df4d0f33173);
+    /// base1.bool(); // Use the generator once.
+    ///
+    /// let mut base2 = fastrand::Rng::with_seed(0x4d595df4d0f33173);
+    /// base2.bool(); // Use the generator once.
+    ///
+    /// let mut rng1 = base1.fork();
+    /// let mut rng2 = base2.fork();
+    ///
+    /// println!("rng1 returns {}", rng1.u32(..));
+    /// println!("rng2 returns {}", rng2.u32(..));
+    /// ```
+    #[inline]
+    #[must_use = "this creates a new instance of `Rng`"]
+    pub fn fork(&mut self) -> Self {
+        Rng::with_seed(self.gen_u64())
+    }
+
+    /// Generates a random `char` in ranges a-z and A-Z.
+    #[inline]
+    pub fn alphabetic(&mut self) -> char {
+        const CHARS: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+        *self.choice(CHARS).unwrap() as char
+    }
+
+    /// Generates a random `char` in ranges a-z, A-Z and 0-9.
+    #[inline]
+    pub fn alphanumeric(&mut self) -> char {
+        const CHARS: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+        *self.choice(CHARS).unwrap() as char
+    }
+
+    /// Generates a random `bool`.
+    #[inline]
+    pub fn bool(&mut self) -> bool {
+        self.u8(..) % 2 == 0
+    }
+
+    /// Generates a random digit in the given `base`.
+    ///
+    /// Digits are represented by `char`s in ranges 0-9 and a-z.
+    ///
+    /// Panics if the base is zero or greater than 36.
+    #[inline]
+    pub fn digit(&mut self, base: u32) -> char {
+        if base == 0 {
+            panic!("base cannot be zero");
+        }
+        if base > 36 {
+            panic!("base cannot be larger than 36");
+        }
+        let num = self.u8(..base as u8);
+        if num < 10 {
+            (b'0' + num) as char
+        } else {
+            (b'a' + num - 10) as char
+        }
+    }
+
+    /// Generates a random `f32` in range `0..1`.
+    pub fn f32(&mut self) -> f32 {
+        let b = 32;
+        let f = core::f32::MANTISSA_DIGITS - 1;
+        f32::from_bits((1 << (b - 2)) - (1 << f) + (self.u32(..) >> (b - f))) - 1.0
+    }
+
+    /// Generates a random `f64` in range `0..1`.
+    pub fn f64(&mut self) -> f64 {
+        let b = 64;
+        let f = core::f64::MANTISSA_DIGITS - 1;
+        f64::from_bits((1 << (b - 2)) - (1 << f) + (self.u64(..) >> (b - f))) - 1.0
+    }
+
+    /// Collects `amount` values at random from the iterator into a vector.
+    ///
+    /// The length of the returned vector equals `amount` unless the iterator
+    /// contains insufficient elements, in which case it equals the number of
+    /// elements available.
+    ///
+    /// Complexity is `O(n)` where `n` is the length of the iterator.
+    #[cfg(feature = "alloc")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
+    pub fn choose_multiple<T: Iterator>(&mut self, mut source: T, amount: usize) -> Vec<T::Item> {
+        // Adapted from: https://docs.rs/rand/latest/rand/seq/trait.IteratorRandom.html#method.choose_multiple
+        let mut reservoir = Vec::with_capacity(amount);
+
+        reservoir.extend(source.by_ref().take(amount));
+
+        // Continue unless the iterator was exhausted
+        //
+        // note: this prevents iterators that "restart" from causing problems.
+        // If the iterator stops once, then so do we.
+        if reservoir.len() == amount {
+            for (i, elem) in source.enumerate() {
+                let end = i + 1 + amount;
+                let k = self.usize(0..end);
+                if let Some(slot) = reservoir.get_mut(k) {
+                    *slot = elem;
+                }
+            }
+        } else {
+            // If less than one third of the `Vec` was used, reallocate
+            // so that the unused space is not wasted. There is a corner
+            // case where `amount` was much less than `self.len()`.
+            if reservoir.capacity() > 3 * reservoir.len() {
+                reservoir.shrink_to_fit();
+            }
+        }
+        reservoir
+    }
+
+    rng_integer!(
+        i8,
+        u8,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `i8` in the given range."
+    );
+
+    rng_integer!(
+        i16,
+        u16,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `i16` in the given range."
+    );
+
+    rng_integer!(
+        i32,
+        u32,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `i32` in the given range."
+    );
+
+    rng_integer!(
+        i64,
+        u64,
+        gen_u64,
+        gen_mod_u64,
+        "Generates a random `i64` in the given range."
+    );
+
+    rng_integer!(
+        i128,
+        u128,
+        gen_u128,
+        gen_mod_u128,
+        "Generates a random `i128` in the given range."
+    );
+
+    #[cfg(target_pointer_width = "16")]
+    rng_integer!(
+        isize,
+        usize,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `isize` in the given range."
+    );
+    #[cfg(target_pointer_width = "32")]
+    rng_integer!(
+        isize,
+        usize,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `isize` in the given range."
+    );
+    #[cfg(target_pointer_width = "64")]
+    rng_integer!(
+        isize,
+        usize,
+        gen_u64,
+        gen_mod_u64,
+        "Generates a random `isize` in the given range."
+    );
+
+    /// Generates a random `char` in range a-z.
+    #[inline]
+    pub fn lowercase(&mut self) -> char {
+        const CHARS: &[u8] = b"abcdefghijklmnopqrstuvwxyz";
+        *self.choice(CHARS).unwrap() as char
+    }
+
+    /// Initializes this generator with the given seed.
+    #[inline]
+    pub fn seed(&mut self, seed: u64) {
+        self.0 = seed;
+    }
+
+    /// Gives back **current** seed that is being held by this generator.
+    #[inline]
+    pub fn get_seed(&self) -> u64 {
+        self.0
+    }
+
+    /// Choose an item from an iterator at random.
+    ///
+    /// This function may have an unexpected result if the `len()` property of the
+    /// iterator does not match the actual number of items in the iterator. If
+    /// the iterator is empty, this returns `None`.
+    #[inline]
+    pub fn choice<I>(&mut self, iter: I) -> Option<I::Item>
+    where
+        I: IntoIterator,
+        I::IntoIter: ExactSizeIterator,
+    {
+        let mut iter = iter.into_iter();
+
+        // Get the item at a random index.
+        let len = iter.len();
+        if len == 0 {
+            return None;
+        }
+        let index = self.usize(0..len);
+
+        iter.nth(index)
+    }
+
+    /// Shuffles a slice randomly.
+    #[inline]
+    pub fn shuffle<T>(&mut self, slice: &mut [T]) {
+        for i in 1..slice.len() {
+            slice.swap(i, self.usize(..=i));
+        }
+    }
+
+    /// Fill a byte slice with random data.
+    #[inline]
+    pub fn fill(&mut self, slice: &mut [u8]) {
+        // We fill the slice by chunks of 8 bytes, or one block of
+        // WyRand output per new state.
+        let mut chunks = slice.chunks_exact_mut(core::mem::size_of::<u64>());
+        for chunk in chunks.by_ref() {
+            let n = self.gen_u64().to_ne_bytes();
+            // Safe because the chunks are always 8 bytes exactly.
+            chunk.copy_from_slice(&n);
+        }
+
+        let remainder = chunks.into_remainder();
+
+        // Any remainder will always be less than 8 bytes.
+        if !remainder.is_empty() {
+            // Generate one last block of 8 bytes of entropy
+            let n = self.gen_u64().to_ne_bytes();
+
+            // Use the remaining length to copy from block
+            remainder.copy_from_slice(&n[..remainder.len()]);
+        }
+    }
+
+    rng_integer!(
+        u8,
+        u8,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `u8` in the given range."
+    );
+
+    rng_integer!(
+        u16,
+        u16,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `u16` in the given range."
+    );
+
+    rng_integer!(
+        u32,
+        u32,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `u32` in the given range."
+    );
+
+    rng_integer!(
+        u64,
+        u64,
+        gen_u64,
+        gen_mod_u64,
+        "Generates a random `u64` in the given range."
+    );
+
+    rng_integer!(
+        u128,
+        u128,
+        gen_u128,
+        gen_mod_u128,
+        "Generates a random `u128` in the given range."
+    );
+
+    #[cfg(target_pointer_width = "16")]
+    rng_integer!(
+        usize,
+        usize,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `usize` in the given range."
+    );
+    #[cfg(target_pointer_width = "32")]
+    rng_integer!(
+        usize,
+        usize,
+        gen_u32,
+        gen_mod_u32,
+        "Generates a random `usize` in the given range."
+    );
+    #[cfg(target_pointer_width = "64")]
+    rng_integer!(
+        usize,
+        usize,
+        gen_u64,
+        gen_mod_u64,
+        "Generates a random `usize` in the given range."
+    );
+    #[cfg(target_pointer_width = "128")]
+    rng_integer!(
+        usize,
+        usize,
+        gen_u128,
+        gen_mod_u128,
+        "Generates a random `usize` in the given range."
+    );
+
+    /// Generates a random `char` in range A-Z.
+    #[inline]
+    pub fn uppercase(&mut self) -> char {
+        const CHARS: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+        *self.choice(CHARS).unwrap() as char
+    }
+
+    /// Generates a random `char` in the given range.
+    ///
+    /// Panics if the range is empty.
+    #[inline]
+    pub fn char(&mut self, range: impl RangeBounds<char>) -> char {
+        let panic_empty_range = || {
+            panic!(
+                "empty range: {:?}..{:?}",
+                range.start_bound(),
+                range.end_bound()
+            )
+        };
+
+        let surrogate_start = 0xd800u32;
+        let surrogate_len = 0x800u32;
+
+        let low = match range.start_bound() {
+            Bound::Unbounded => 0u8 as char,
+            Bound::Included(&x) => x,
+            Bound::Excluded(&x) => {
+                let scalar = if x as u32 == surrogate_start - 1 {
+                    surrogate_start + surrogate_len
+                } else {
+                    x as u32 + 1
+                };
+                char::try_from(scalar).unwrap_or_else(|_| panic_empty_range())
+            }
+        };
+
+        let high = match range.end_bound() {
+            Bound::Unbounded => core::char::MAX,
+            Bound::Included(&x) => x,
+            Bound::Excluded(&x) => {
+                let scalar = if x as u32 == surrogate_start + surrogate_len {
+                    surrogate_start - 1
+                } else {
+                    (x as u32).wrapping_sub(1)
+                };
+                char::try_from(scalar).unwrap_or_else(|_| panic_empty_range())
+            }
+        };
+
+        if low > high {
+            panic_empty_range();
+        }
+
+        let gap = if (low as u32) < surrogate_start && (high as u32) >= surrogate_start {
+            surrogate_len
+        } else {
+            0
+        };
+        let range = high as u32 - low as u32 - gap;
+        let mut val = self.u32(0..=range) + low as u32;
+        if val >= surrogate_start {
+            val += gap;
+        }
+        val.try_into().unwrap()
+    }
+}