Clean a bit + tests

days/src/main/kotlin/Day03.kt

@@ -18,13 +18,11 @@ class Day03(@Lines val input: Input<List<String>>) {
 
         val width = grid.first().length
 
-        while (true) {
+        while (y < grid.size - 1) {
             x += slope.x
             y += slope.y
 
-            if (x >= width) x -= width
-            if (y >= grid.size) break
-            if (grid[y][x] == '#') trees++
+            if (grid[y][x % width] == '#') trees++
         }
 
         return trees
@@ -37,15 +35,11 @@ class Day03(@Lines val input: Input<List<String>>) {
         Slope(x = 7, y = 1),
         Slope(x = 1, y = 2),
     )
-        .map { it to part1(it) }
-        .onEach { println("$it") }
-        .map { it.second.toLong() }
+        .map { part1(it).toLong() }
         .reduce { acc, trees -> acc * trees }
 }
 
-fun main() {
-    with(createDay<Day03>()) {
-        println(part1().also { check(it == 294) })
-        println(part2().also { check(it == 5774564250) })
-    }
+fun main() = with(createDay<Day03>()) {
+    println(part1())
+    println(part2())
 }

days/src/test/kotlin/Day03Test.kt

@@ -0,0 +1,56 @@
+package be.vandewalleh.aoc.days
+
+import be.vandewalleh.aoc.utils.input.Input
+import be.vandewalleh.aoc.utils.input.createDay
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+
+class Day03Test {
+
+    @Nested
+    inner class Example {
+        private val example = listOf(
+            "..##.......",
+            "#...#...#..",
+            ".#....#..#.",
+            "..#.#...#.#",
+            ".#...##..#.",
+            "..#.##.....",
+            ".#.#.#....#",
+            ".#........#",
+            "#.##...#...",
+            "#...##....#",
+            ".#..#...#.#",
+        ).let { Input(it) }
+
+        private val day03 = Day03(example)
+
+        @Test
+        fun `part1 result`() {
+            assertThat(day03.part1()).isEqualTo(7)
+        }
+
+        @Test
+        fun `part2 result`() {
+            assertThat(day03.part2()).isEqualTo(336)
+        }
+    }
+
+
+    @Nested
+    inner class RealInput {
+        private val day03 = createDay<Day03>()
+
+        @Test
+        fun `part1 result`() {
+            assertThat(day03.part1()).isEqualTo(294)
+        }
+
+        @Test
+        fun `part2 result`() {
+            assertThat(day03.part2()).isEqualTo(5774564250)
+        }
+    }
+
+}