chore: checkpoint before Python removal

vendor/itoa/benches/bench.rs

@@ -0,0 +1,41 @@
+use criterion::{criterion_group, criterion_main, Criterion};
+use std::fmt::Display;
+use std::hint;
+use std::io::Write;
+
+fn do_bench(c: &mut Criterion, group_name: &str, int: impl itoa::Integer + Display) {
+    let mut group = c.benchmark_group(group_name);
+    group.bench_function("itoa", |b| {
+        let mut buf = itoa::Buffer::new();
+        b.iter(move || {
+            let int = hint::black_box(int);
+            let formatted = buf.format(int);
+            hint::black_box(formatted);
+        });
+    });
+    group.bench_function("std::fmt", |b| {
+        let mut buf = Vec::with_capacity(20);
+        b.iter(|| {
+            buf.clear();
+            let int = hint::black_box(int);
+            write!(&mut buf, "{int}").unwrap();
+            hint::black_box(buf.as_slice());
+        });
+    });
+    group.finish();
+}
+
+fn bench(c: &mut Criterion) {
+    do_bench(c, "u64[0]", 0u64);
+    do_bench(c, "u64[half]", u64::from(u32::MAX));
+    do_bench(c, "u64[max]", u64::MAX);
+
+    do_bench(c, "i16[0]", 0i16);
+    do_bench(c, "i16[min]", i16::MIN);
+
+    do_bench(c, "u128[0]", 0u128);
+    do_bench(c, "u128[max]", u128::MAX);
+}
+
+criterion_group!(benches, bench);
+criterion_main!(benches);