Make Day20's implementation a class, express the small examples as tests

Coverage:
- class: 78%
- method: 83%
- line: 83%
- branch: 85%

Author: rhaendel

…lin/de/ronny_h/aoc/year24/day20/Day20.kt …onny_h/aoc/year24/day20/RaceCondition.ktsrc/main/kotlin/de/ronny_h/aoc/year24/day20/Day20.kt renamed to src/main/kotlin/de/ronny_h/aoc/year24/day20/RaceCondition.kt src/main/kotlin/de/ronny_h/aoc/year24/day20/Day20.kt renamed to src/main/kotlin/de/ronny_h/aoc/year24/day20/RaceCondition.kt

@@ -10,7 +10,17 @@ import readInput
 
 fun main() {
     val day = "Day20"
+    val input = readInput(day)
+    val raceCondition = RaceCondition()
+
+    println("$day part 1")
+    printAndCheck(input, raceCondition::part1Large, 1438)
 
+    println("$day part 2")
+    printAndCheck(input, raceCondition::part2Large, 1026446)
+}
+
+class RaceCondition {
     fun part1(input: List<String>, minPicosecondsSaved: Int, shortcutMaxLength: Int): Int {
         val track = RaceTrack(input)
         track.printGrid()
@@ -23,35 +33,6 @@ fun main() {
     fun part2Small(input: List<String>) = part1(input, 76, 20)
     fun part2Large(input: List<String>) = part1(input, 100, 20)
 
-    println("$day part 1")
-
-    val testInput = """
-        ###############
-        #...#...#.....#
-        #.#.#.#.#.###.#
-        #S#...#.#.#...#
-        #######.#.#.###
-        #######.#.#...#
-        #######.#.###.#
-        ###..E#...#...#
-        ###.#######.###
-        #...###...#...#
-        #.#####.#.###.#
-        #.#...#.#.#...#
-        #.#.#.#.#.#.###
-        #...#...#...###
-        ###############
-    """.trimIndent().split('\n')
-    printAndCheck(testInput, ::part1Small, 10)
-
-    val input = readInput(day)
-    printAndCheck(input, ::part1Large, 1438)
-
-
-    println("$day part 2")
-
-    printAndCheck(testInput, ::part2Small, 3)
-    printAndCheck(input, ::part2Large, 1026446)
 }
 
 private class RaceTrack(input: List<String>) : Grid<Char>(input, '#') {

src/test/kotlin/de/ronny_h/aoc/year24/day20/RaceConditionTest.kt

@@ -0,0 +1,33 @@
+package de.ronny_h.aoc.year24.day20
+
+import de.ronny_h.aoc.extensions.asList
+import io.kotest.core.spec.style.StringSpec
+import io.kotest.matchers.shouldBe
+
+class RaceConditionTest : StringSpec({
+    val input = """
+        ###############
+        #...#...#.....#
+        #.#.#.#.#.###.#
+        #S#...#.#.#...#
+        #######.#.#.###
+        #######.#.#...#
+        #######.#.###.#
+        ###..E#...#...#
+        ###.#######.###
+        #...###...#...#
+        #.#####.#.###.#
+        #.#...#.#.#...#
+        #.#.#.#.#.#.###
+        #...#...#...###
+        ###############
+    """.asList()
+
+    "part 1: Number of 2ps cheats saving at least 10 picoseconds" {
+        RaceCondition().part1Small(input) shouldBe 10
+    }
+
+    "part 2: Number of 20ps cheats saving at least 76 picoseconds" {
+        RaceCondition().part2Small(input) shouldBe 3
+    }
+})