Add criterion benchmarks

2020/Cargo.toml

@@ -11,5 +11,12 @@ itertools = "0.9"
 num-integer = "0.1"
 regex = "1"
 
+[dev-dependencies]
+criterion = "0.3"
+
 [profile.release]
 debug = true
+
+[[bench]]
+name = "days"
+harness = false

2020/benches/days.rs

@@ -0,0 +1,47 @@
+use std::fs::File;
+use std::io::Read;
+
+use aoc_2020::get_implementation;
+use criterion::criterion_group;
+use criterion::criterion_main;
+use criterion::BenchmarkId;
+use criterion::Criterion;
+
+const DAYS_IMPLEMENTED: usize = 19;
+
+fn read_input(day: usize) -> Vec<u8> {
+    let input_path = format!("inputs/{:02}.txt", day);
+
+    let mut buffer = Vec::new();
+    File::open(input_path)
+        .expect("Failed to open input file")
+        .read_to_end(&mut buffer)
+        .expect("Failed to read input file");
+
+    buffer
+}
+
+pub fn benchmark_days(c: &mut Criterion) {
+    for day in 1..=DAYS_IMPLEMENTED {
+        let input = read_input(day);
+
+        c.bench_with_input(BenchmarkId::new("part1", day), &input, |b, i| {
+            b.iter(|| {
+                let mut implementation = get_implementation(day);
+                let mut i: &[u8] = &i;
+                implementation.part1(&mut i)
+            });
+        });
+
+        c.bench_with_input(BenchmarkId::new("part2", day), &input, |b, i| {
+            b.iter(|| {
+                let mut implementation = get_implementation(day);
+                let mut i: &[u8] = &i;
+                implementation.part2(&mut i)
+            });
+        });
+    }
+}
+
+criterion_group!(benches, benchmark_days);
+criterion_main!(benches);