refactor: make API independent of array

Author: coderbyheart

day22/cardshuffle.ts

@@ -47,3 +47,9 @@ export const parseActions = (actions: string): CardAction[] =>
 
 export const cardShuffle = (actions: CardAction[]) => (deck: Deck): Deck =>
 	actions.reduce((deck, action) => action(deck), deck)
+
+export const deckOf = (length: number): number[] =>
+	[...Array(length)].map((_, i) => i)
+
+export const positionInDeck = (deck: Deck) => (card: number) =>
+	deck.indexOf(card)

day22/day21.solution.spec.ts

@@ -0,0 +1,21 @@
+import {
+	cardShuffle,
+	parseActions,
+	deckOf,
+	positionInDeck,
+} from './cardshuffle'
+import * as fs from 'fs'
+import * as path from 'path'
+
+const actions = fs.readFileSync(
+	path.resolve(process.cwd(), 'day22/input.txt'),
+	'utf-8',
+)
+
+describe('Day 22: Part 1', () => {
+	it('should solve the puzzle', () => {
+		const deck = deckOf(10007)
+		const shuffled = cardShuffle(parseActions(actions))(deck)
+		expect(positionInDeck(shuffled)(2019)).toEqual(3749)
+	})
+})