helper

helper/src/lib.rs

@@ -1,5 +1,60 @@
+use std::borrow::Cow;
+
 use nom::{character::complete::digit1, combinator::map, IResult};
 
+pub type Solution = fn(&str) -> u64;
+
+pub trait Day {
+    fn part1() -> Variants;
+
+    fn part2() -> Variants;
+
+    /// Pad or manipulate the input in ways that don't necessarily
+    /// change it but do things that may be sound or unsound.
+    fn pad_input(input: &str) -> Cow<str> {
+        Cow::Borrowed(input)
+    }
+}
+
+pub struct Variants {
+    pub variants: Vec<Variant>,
+}
+
+pub struct Variant {
+    pub name: &'static str,
+    pub f: Solution,
+}
+
+impl Variants {
+    pub fn basic(f: Solution) -> Self {
+        Variants {
+            variants: vec![Variant { name: "basic", f }],
+        }
+    }
+}
+
+pub fn test_part1<D: Day>(inputs: &[(&str, u64)]) {
+    for variant in D::part1().variants {
+        for input in inputs {
+            let actual = (variant.f)(input.0);
+            if actual != input.1 {
+                panic!("failed: {}: {actual} != {}", variant.name, input.1);
+            }
+        }
+    }
+}
+
+pub fn test_part2<D: Day>(inputs: &[(&str, u64)]) {
+    for variant in D::part2().variants {
+        for input in inputs {
+            let actual = (variant.f)(input.0);
+            if actual != input.1 {
+                panic!("failed: {}: {actual} != {}", variant.name, input.1);
+            }
+        }
+    }
+}
+
 pub fn integer(input: &str) -> IResult<&str, u64> {
     map(digit1, |d: &str| d.parse::<u64>().unwrap())(input)
 }