1 files changed, 125 insertions, 0 deletions
diff --git a/third_party/rust/itertools/benches/combinations.rs b/third_party/rust/itertools/benches/combinations.rs
new file mode 100644
index 0000000000..e7433a4cb0
--- /dev/null
+++ b/third_party/rust/itertools/benches/combinations.rs
@@ -0,0 +1,125 @@
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+use itertools::Itertools;
+
+// approximate 100_000 iterations for each combination
+const N1: usize = 100_000;
+const N2: usize = 448;
+const N3: usize = 86;
+const N4: usize = 41;
+const N14: usize = 21;
+
+fn comb_for1(c: &mut Criterion) {
+    c.bench_function("comb for1", move |b| {
+        b.iter(|| {
+            for i in 0..N1 {
+                black_box(vec![i]);
+            }
+        })
+    });
+}
+
+fn comb_for2(c: &mut Criterion) {
+    c.bench_function("comb for2", move |b| {
+        b.iter(|| {
+            for i in 0..N2 {
+                for j in (i + 1)..N2 {
+                    black_box(vec![i, j]);
+                }
+            }
+        })
+    });
+}
+
+fn comb_for3(c: &mut Criterion) {
+    c.bench_function("comb for3", move |b| {
+        b.iter(|| {
+            for i in 0..N3 {
+                for j in (i + 1)..N3 {
+                    for k in (j + 1)..N3 {
+                        black_box(vec![i, j, k]);
+                    }
+                }
+            }
+        })
+    });
+}
+
+fn comb_for4(c: &mut Criterion) {
+    c.bench_function("comb for4", move |b| {
+        b.iter(|| {
+            for i in 0..N4 {
+                for j in (i + 1)..N4 {
+                    for k in (j + 1)..N4 {
+                        for l in (k + 1)..N4 {
+                            black_box(vec![i, j, k, l]);
+                        }
+                    }
+                }
+            }
+        })
+    });
+}
+
+fn comb_c1(c: &mut Criterion) {
+    c.bench_function("comb c1", move |b| {
+        b.iter(|| {
+            for combo in (0..N1).combinations(1) {
+                black_box(combo);
+            }
+        })
+    });
+}
+
+fn comb_c2(c: &mut Criterion) {
+    c.bench_function("comb c2", move |b| {
+        b.iter(|| {
+            for combo in (0..N2).combinations(2) {
+                black_box(combo);
+            }
+        })
+    });
+}
+
+fn comb_c3(c: &mut Criterion) {
+    c.bench_function("comb c3", move |b| {
+        b.iter(|| {
+            for combo in (0..N3).combinations(3) {
+                black_box(combo);
+            }
+        })
+    });
+}
+
+fn comb_c4(c: &mut Criterion) {
+    c.bench_function("comb c4", move |b| {
+        b.iter(|| {
+            for combo in (0..N4).combinations(4) {
+                black_box(combo);
+            }
+        })
+    });
+}
+
+fn comb_c14(c: &mut Criterion) {
+    c.bench_function("comb c14", move |b| {
+        b.iter(|| {
+            for combo in (0..N14).combinations(14) {
+                black_box(combo);
+            }
+        })
+    });
+}
+
+criterion_group!(
+    benches,
+    comb_for1,
+    comb_for2,
+    comb_for3,
+    comb_for4,
+    comb_c1,
+    comb_c2,
+    comb_c3,
+    comb_c4,
+    comb_c14,
+);
+criterion_main!(benches);