Use a macro for benchmarking.

With this macro the code needed for a new benchmark is minimal, but not
small enough IMO. Unfortunately, a better version would require
concat_ident, which is not going to happen soon.

2018/benches/days.rs

@@ -2,48 +2,75 @@ extern crate aoc_2018;
 #[macro_use]
 extern crate bencher;
 
+use std::fs::File;
+use std::io::Read;
+
 use bencher::Bencher;
 
 use aoc_2018::get_impl;
 
-const INPUTS: &[&[u8]] = &[
-    include_bytes!("../inputs/01.txt"),
-    include_bytes!("../inputs/02.txt"),
-];
+fn get_input(day: u32) -> Vec<u8> {
+    let filename = format!("inputs/{:02}.txt", day);
+
+    let mut buf = Vec::new();
+    let mut file = File::open(&filename).unwrap();
+
+    file.read_to_end(&mut buf).unwrap();
+
+    buf
+}
 
 fn test_part1(day: u32, bench: &mut Bencher) {
+    let input = get_input(day);
     bench.iter(|| {
-        let input = INPUTS[day as usize - 1];
         let mut instance = get_impl(day);
-        instance.part1(&mut input.as_ref())
+        instance.part1(&mut input.as_slice())
     })
 }
 
 fn test_part2(day: u32, bench: &mut Bencher) {
+    let input = get_input(day);
     bench.iter(|| {
-        let input = INPUTS[day as usize - 1];
         let mut instance = get_impl(day);
-        instance.part2(&mut input.as_ref())
+        instance.part2(&mut input.as_slice())
     })
 }
 
-fn day1_part1(bench: &mut Bencher) {
-    test_part1(1, bench)
+macro_rules! day_bench {
+
+    ( $name:ident, $day:expr ) => {
+            pub mod $name {
+                use super::*;
+                pub fn part1(bench: & mut Bencher) {
+                test_part1( $day, bench);
+                }
+                pub fn part2(bench: & mut Bencher) {
+                test_part2( $day, bench);
+                }
+            }
+            benchmark_group!( $name, $name::part1, $name::part2);
+    };
 }
 
-fn day1_part2(bench: &mut Bencher) {
-    test_part2(1, bench)
-}
+day_bench!(day01, 1);
+day_bench!(day02, 2);
+day_bench!(day03, 3);
+day_bench!(day04, 4);
+day_bench!(day05, 5);
+day_bench!(day06, 6);
+day_bench!(day07, 7);
+day_bench!(day08, 8);
+day_bench!(day09, 9);
+day_bench!(day10, 10);
+day_bench!(day11, 11);
+day_bench!(day12, 12);
+day_bench!(day13, 13);
+day_bench!(day14, 14);
+day_bench!(day15, 15);
+day_bench!(day16, 16);
+day_bench!(day17, 17);
 
-fn day2_part1(bench: &mut Bencher) {
-    test_part1(2, bench)
-}
-
-fn day2_part2(bench: &mut Bencher) {
-    test_part2(2, bench)
-}
-
-benchmark_group!(day1, day1_part1, day1_part2);
-benchmark_group!(day2, day2_part1, day2_part2);
-
-benchmark_main!(day1, day2);
+benchmark_main!(day01, day02, day03, day04, day05,
+                day06, day07, day08, day09, day10,
+                day11, day12, day13, day14, day15,
+                day16, day17);