1 files changed, 130 insertions, 0 deletions
diff --git a/tests/octillion.rs b/tests/octillion.rs
new file mode 100644
index 0000000..cff2b11
--- /dev/null
+++ b/tests/octillion.rs
@@ -0,0 +1,130 @@
+use rayon::prelude::*;
+
+const OCTILLION: u128 = 1_000_000_000_000_000_000_000_000_000;
+
+/// Produce a parallel iterator for 0u128..10²⁷
+fn octillion() -> rayon::range::Iter<u128> {
+    (0..OCTILLION).into_par_iter()
+}
+
+/// Produce a parallel iterator for 0u128..=10²⁷
+fn octillion_inclusive() -> rayon::range_inclusive::Iter<u128> {
+    (0..=OCTILLION).into_par_iter()
+}
+
+/// Produce a parallel iterator for 0u128..10²⁷ using `flat_map`
+fn octillion_flat() -> impl ParallelIterator<Item = u128> {
+    (0u32..1_000_000_000)
+        .into_par_iter()
+        .with_max_len(1_000)
+        .map(|i| u64::from(i) * 1_000_000_000)
+        .flat_map(|i| {
+            (0u32..1_000_000_000)
+                .into_par_iter()
+                .with_max_len(1_000)
+                .map(move |j| i + u64::from(j))
+        })
+        .map(|i| u128::from(i) * 1_000_000_000)
+        .flat_map(|i| {
+            (0u32..1_000_000_000)
+                .into_par_iter()
+                .with_max_len(1_000)
+                .map(move |j| i + u128::from(j))
+        })
+}
+
+// NOTE: `find_first` and `find_last` currently take too long on 32-bit targets,
+// because the `AtomicUsize` match position has much too limited resolution.
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_first_octillion() {
+    let x = octillion().find_first(|_| true);
+    assert_eq!(x, Some(0));
+}
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_first_octillion_inclusive() {
+    let x = octillion_inclusive().find_first(|_| true);
+    assert_eq!(x, Some(0));
+}
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_first_octillion_flat() {
+    let x = octillion_flat().find_first(|_| true);
+    assert_eq!(x, Some(0));
+}
+
+fn two_threads<F: Send + FnOnce() -> R, R: Send>(f: F) -> R {
+    // FIXME: If we don't use at least two threads, then we end up walking
+    // through the entire iterator sequentially, without the benefit of any
+    // short-circuiting.  We probably don't want testing to wait that long. ;)
+    let builder = rayon::ThreadPoolBuilder::new().num_threads(2);
+    let pool = builder.build().unwrap();
+
+    pool.install(f)
+}
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_last_octillion() {
+    // It would be nice if `find_last` could prioritize the later splits,
+    // basically flipping the `join` args, without needing indexed `rev`.
+    // (or could we have an unindexed `rev`?)
+    let x = two_threads(|| octillion().find_last(|_| true));
+    assert_eq!(x, Some(OCTILLION - 1));
+}
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_last_octillion_inclusive() {
+    let x = two_threads(|| octillion_inclusive().find_last(|_| true));
+    assert_eq!(x, Some(OCTILLION));
+}
+
+#[test]
+#[cfg_attr(not(target_pointer_width = "64"), ignore)]
+fn find_last_octillion_flat() {
+    let x = two_threads(|| octillion_flat().find_last(|_| true));
+    assert_eq!(x, Some(OCTILLION - 1));
+}
+
+#[test]
+fn find_any_octillion() {
+    let x = two_threads(|| octillion().find_any(|x| *x > OCTILLION / 2));
+    assert!(x.is_some());
+}
+
+#[test]
+fn find_any_octillion_flat() {
+    let x = two_threads(|| octillion_flat().find_any(|x| *x > OCTILLION / 2));
+    assert!(x.is_some());
+}
+
+#[test]
+fn filter_find_any_octillion() {
+    let x = two_threads(|| {
+        octillion()
+            .filter(|x| *x > OCTILLION / 2)
+            .find_any(|_| true)
+    });
+    assert!(x.is_some());
+}
+
+#[test]
+fn filter_find_any_octillion_flat() {
+    let x = two_threads(|| {
+        octillion_flat()
+            .filter(|x| *x > OCTILLION / 2)
+            .find_any(|_| true)
+    });
+    assert!(x.is_some());
+}
+
+#[test]
+fn fold_find_any_octillion_flat() {
+    let x = two_threads(|| octillion_flat().fold(|| (), |_, _| ()).find_any(|_| true));
+    assert!(x.is_some());
+}