1 files changed, 21 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/stdx/src/rand.rs b/src/tools/rust-analyzer/crates/stdx/src/rand.rs
new file mode 100644
index 000000000..64aa57eae
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/stdx/src/rand.rs
@@ -0,0 +1,21 @@
+//! We don't use `rand`, as that's too many things for us.
+//!
+//! We currently use oorandom instead, but it's missing these two utilities.
+//! Perhaps we should switch to `fastrand`, or our own small PRNG, it's not like
+//! we need anything more complicated than xor-shift.
+
+pub fn shuffle<T>(slice: &mut [T], mut rand_index: impl FnMut(usize) -> usize) {
+    let mut remaining = slice.len() - 1;
+    while remaining > 0 {
+        let index = rand_index(remaining);
+        slice.swap(remaining, index);
+        remaining -= 1;
+    }
+}
+
+pub fn seed() -> u64 {
+    use std::collections::hash_map::RandomState;
+    use std::hash::{BuildHasher, Hasher};
+
+    RandomState::new().build_hasher().finish()
+}