add random shuffle util

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/utils/mod.rs

@@ -30,7 +30,7 @@ pub use self::{
 	json::{deserialize_from_str, to_canonical_object},
 	math::clamp,
 	mutex_map::{Guard as MutexMapGuard, MutexMap},
-	rand::string as random_string,
+	rand::{shuffle, string as random_string},
 	stream::{IterStream, ReadyExt, Tools as StreamTools, TryReadyExt},
 	string::{str_from_bytes, string_from_bytes},
 	sys::available_parallelism,

src/core/utils/rand.rs

@@ -4,7 +4,12 @@ use std::{
 };
 
 use arrayvec::ArrayString;
-use rand::{thread_rng, Rng};
+use rand::{seq::SliceRandom, thread_rng, Rng};
+
+pub fn shuffle<T>(vec: &mut [T]) {
+	let mut rng = thread_rng();
+	vec.shuffle(&mut rng);
+}
 
 pub fn string(length: usize) -> String {
 	thread_rng()