2 files changed, 164 insertions, 0 deletions
diff --git a/third_party/rust/fastrand/tests/char.rs b/third_party/rust/fastrand/tests/char.rs
new file mode 100644
index 0000000000..0f48c57708
--- /dev/null
+++ b/third_party/rust/fastrand/tests/char.rs
@@ -0,0 +1,44 @@
+use std::convert::TryFrom;
+use std::ops::RangeBounds;
+
+fn test_char_coverage<R>(n: usize, range: R)
+where
+    R: Iterator<Item = char> + RangeBounds<char> + Clone,
+{
+    use std::collections::HashSet;
+
+    let all: HashSet<char> = range.clone().collect();
+    let mut covered = HashSet::new();
+    for _ in 0..n {
+        let c = fastrand::char(range.clone());
+        assert!(all.contains(&c));
+        covered.insert(c);
+    }
+    assert_eq!(covered, all);
+}
+
+#[test]
+fn test_char() {
+    // ASCII control chars.
+    let nul = 0u8 as char;
+    let soh = 1u8 as char;
+    let stx = 2u8 as char;
+    // Some undefined Hangul Jamo codepoints just before
+    // the surrogate area.
+    let last_jamo = char::try_from(0xd7ffu32).unwrap();
+    let penultimate_jamo = char::try_from(last_jamo as u32 - 1).unwrap();
+    // Private-use codepoints just after the surrogate area.
+    let first_private = char::try_from(0xe000u32).unwrap();
+    let second_private = char::try_from(first_private as u32 + 1).unwrap();
+    // Private-use codepoints at the end of Unicode space.
+    let last_private = std::char::MAX;
+    let penultimate_private = char::try_from(last_private as u32 - 1).unwrap();
+
+    test_char_coverage(100, nul..stx);
+    test_char_coverage(100, nul..=soh);
+
+    test_char_coverage(400, penultimate_jamo..second_private);
+    test_char_coverage(400, penultimate_jamo..=second_private);
+
+    test_char_coverage(100, penultimate_private..=last_private);
+}
diff --git a/third_party/rust/fastrand/tests/smoke.rs b/third_party/rust/fastrand/tests/smoke.rs
new file mode 100644
index 0000000000..ff3cea66db
--- /dev/null
+++ b/third_party/rust/fastrand/tests/smoke.rs
@@ -0,0 +1,120 @@
+#[cfg(all(target_family = "wasm", not(target_os = "wasi")))]
+use wasm_bindgen_test::wasm_bindgen_test as test;
+
+#[cfg(all(target_family = "wasm", not(target_os = "wasi")))]
+wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
+
+#[test]
+fn bool() {
+    for x in &[false, true] {
+        while fastrand::bool() != *x {}
+    }
+}
+
+#[test]
+fn u8() {
+    for x in 0..10 {
+        while fastrand::u8(..10) != x {}
+    }
+
+    for x in 200..=u8::MAX {
+        while fastrand::u8(200..) != x {}
+    }
+}
+
+#[test]
+fn i8() {
+    for x in -128..-120 {
+        while fastrand::i8(..-120) != x {}
+    }
+
+    for x in 120..=127 {
+        while fastrand::i8(120..) != x {}
+    }
+}
+
+#[test]
+fn u32() {
+    for n in 1u32..10_000 {
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        if n != 0 {
+            for _ in 0..1000 {
+                assert!(fastrand::u32(..n) < n);
+            }
+        }
+    }
+}
+
+#[test]
+fn u64() {
+    for n in 1u64..10_000 {
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        if n != 0 {
+            for _ in 0..1000 {
+                assert!(fastrand::u64(..n) < n);
+            }
+        }
+    }
+}
+
+#[test]
+fn u128() {
+    for n in 1u128..10_000 {
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        let n = n.wrapping_mul(n);
+        if n != 0 {
+            for _ in 0..1000 {
+                assert!(fastrand::u128(..n) < n);
+            }
+        }
+    }
+}
+
+#[test]
+fn fill() {
+    let r = fastrand::Rng::new();
+    let mut a = [0u8; 64];
+    let mut b = [0u8; 64];
+
+    r.fill(&mut a);
+    r.fill(&mut b);
+
+    assert_ne!(a, b);
+}
+
+#[test]
+fn rng() {
+    let r = fastrand::Rng::new();
+
+    assert_ne!(r.u64(..), r.u64(..));
+
+    r.seed(7);
+    let a = r.u64(..);
+    r.seed(7);
+    let b = r.u64(..);
+    assert_eq!(a, b);
+}
+
+#[test]
+fn rng_init() {
+    let a = fastrand::Rng::new();
+    let b = fastrand::Rng::new();
+    assert_ne!(a.u64(..), b.u64(..));
+
+    a.seed(7);
+    b.seed(7);
+    assert_eq!(a.u64(..), b.u64(..));
+}
+
+#[test]
+fn with_seed() {
+    let a = fastrand::Rng::with_seed(7);
+    let b = fastrand::Rng::new();
+    b.seed(7);
+    assert_eq!(a.u64(..), b.u64(..));
+}