Factor out an abstract class providing a scaffolding for all AoC days

Author: rhaendel

.gitignore

@@ -4,5 +4,6 @@
 build
 src/input/**/*.txt
 !src/input/2024/ForTests.txt
+!src/input/2024/Day99.txt
 local.properties
 /.kotlintest/

src/input/2024/Day99.txt

@@ -0,0 +1,5 @@
+This file is just for testing
+line two
+line three
+
+line five

src/main/kotlin/de/ronny_h/aoc/AdventOfCode.kt

@@ -0,0 +1,33 @@
+package de.ronny_h.aoc
+
+import kotlin.io.path.Path
+import kotlin.io.path.readText
+import kotlin.time.TimedValue
+import kotlin.time.measureTimedValue
+
+abstract class AdventOfCode<T>(val year: Int, val day: Int) {
+    abstract fun part1(input: List<String>): T
+    abstract fun part2(input: List<String>): T
+
+    private val input = readInput()
+
+    fun run(expectedPart1: T, expectedPart2: T) {
+        println("Day $day $year, part 1")
+        printAndCheck(::part1, expectedPart1)
+        println("Day $day $year, part 2")
+        printAndCheck(::part2, expectedPart2)
+    }
+
+    private fun readInput() = Path("src/input/$year/Day${paddedDay()}.txt").readText().trim().lines()
+
+    private fun paddedDay(): String = day.toString().padStart(2, '0')
+
+    private fun printAndCheck(block: (List<String>) -> T, expected: T) {
+        printAndCheck(measureTimedValue { block(input) }, expected)
+    }
+
+    private fun printAndCheck(result: TimedValue<T>, expected: T) {
+        println("result: ${result.value}, expected: $expected, took: ${result.duration}")
+        check(result.value == expected)
+    }
+}

src/main/kotlin/de/ronny_h/aoc/year24/day01/HistorianHysteria.kt

@@ -1,23 +1,12 @@
 package de.ronny_h.aoc.year24.day01
 
-import de.ronny_h.aoc.extensions.printAndCheck
-import de.ronny_h.aoc.extensions.readInput
+import de.ronny_h.aoc.AdventOfCode
 import kotlin.math.abs
 
-fun main() {
-    val day = "Day01"
-    val input = readInput(day)
-    val historianHysteria = HistorianHysteria()
+fun main() = HistorianHysteria().run(3714264, 18805872)
 
-    println("$day part 1")
-    printAndCheck(input, historianHysteria::part1, 3714264)
-
-    println("$day part 2")
-    printAndCheck(input, historianHysteria::part2, 18805872)
-}
-
-class HistorianHysteria {
-    fun part1(input: List<String>): Int {
+class HistorianHysteria() : AdventOfCode<Int>(2024, 1) {
+    override fun part1(input: List<String>): Int {
         val teamOne = input
             .filter { it.isNotBlank() }
             .map { it.split("   ").first().toInt() }
@@ -30,7 +19,7 @@ class HistorianHysteria {
         return distances.sum()
     }
 
-    fun part2(input: List<String>): Int {
+    override fun part2(input: List<String>): Int {
         val (teamOne, teamTwo) = input
             .filter { it.isNotBlank() }
             .map {

src/test/kotlin/de/ronny_h/aoc/AdventOfCodeTest.kt

@@ -0,0 +1,30 @@
+package de.ronny_h.aoc
+
+import io.kotest.core.spec.style.StringSpec
+import io.kotest.assertions.throwables.shouldThrow
+import io.kotest.matchers.shouldBe
+
+class AdventOfCodeTest : StringSpec({
+    val adventOfCode = object : AdventOfCode<Int>(2024, 99) {
+        override fun part1(input: List<String>) = input.size
+        override fun part2(input: List<String>) = input.size
+    }
+
+    "The day's file can be read and has the right number of lines" {
+        adventOfCode.run(5, 5)
+    }
+
+    "Failure of part one is detected" {
+        val exception = shouldThrow<IllegalStateException> {
+            adventOfCode.run(4, 5)
+        }
+        exception.message shouldBe "Check failed."
+    }
+
+    "Failure of part two is detected" {
+        val exception = shouldThrow<IllegalStateException> {
+            adventOfCode.run(5, 4)
+        }
+        exception.message shouldBe "Check failed."
+    }
+})