start rand utils suite

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

src/core/utils/rand.rs

@@ -0,0 +1,24 @@
+use std::{
+	ops::Range,
+	time::{Duration, SystemTime},
+};
+
+use rand::{thread_rng, Rng};
+
+pub fn string(length: usize) -> String {
+	thread_rng()
+		.sample_iter(&rand::distributions::Alphanumeric)
+		.take(length)
+		.map(char::from)
+		.collect()
+}
+
+#[inline]
+#[must_use]
+pub fn timepoint_secs(range: Range<u64>) -> SystemTime { SystemTime::now() + secs(range) }
+
+#[must_use]
+pub fn secs(range: Range<u64>) -> Duration {
+	let mut rng = thread_rng();
+	Duration::from_secs(rng.gen_range(range))
+}