day(01): convert sample tests to unit tests

Signed-off-by: Matej Focko <mfocko@redhat.com>

src/bin/day01.rs

@@ -78,12 +78,25 @@ fn main() {
         .compact()
         .init();
 
-    let sample = parse_input("samples/day01.txt");
     let input = parse_input("inputs/day01.txt");
 
-    assert_eq!(part_1(&sample), 24000);
     info!("Part 1: {}", part_1(&input));
-
-    assert_eq!(part_2(&sample), 45000);
     info!("Part 2: {}", part_2(&input));
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_part_1() {
+        let sample = parse_input("samples/day01.txt");
+        assert_eq!(part_1(&sample), 24000);
+    }
+
+    #[test]
+    fn test_part_2() {
+        let sample = parse_input("samples/day01.txt");
+        assert_eq!(part_2(&sample), 45000);
+    }
+}