Add draft te st and fix spanByRarity

src/mlpccg/draft/booster.ts

@@ -192,7 +192,7 @@ export class PackBuilder {
 }
 
 // Yields random cards from a chosen pool
-function* randomProvider(pool: Card[]) {
+export function* randomProvider(pool: Card[]) {
   while (true) {
     const idx = Math.floor(Math.random() * pool.length);
     yield pool[idx];
@@ -201,12 +201,12 @@ function* randomProvider(pool: Card[]) {
 
 // Divides a list of card to a map of rarities
 // ie. [ff14, ff16, ff17] => { "C" : ["ff14"], "U": ["ff17"], "R": ["ff16"] }
-function spanByRarity(pool: Card[]): Record<string, Card[]> {
+export function spanByRarity(pool: Card[]): Record<string, Card[]> {
   return pool.reduce((map, current) => {
     if (!(current.Rarity in map)) {
       map[current.Rarity] = [];
     }
-    map[current.Rarity] = current;
+    map[current.Rarity].push(current);
     return map;
   }, Object.create(null));
 }

src/mlpccg/draft/index.ts

@@ -0,0 +1,3 @@
+export * from "./cube";
+export * from "./booster";
+export * from "./types";

src/tests/unit/draft.spec.ts

@@ -0,0 +1,25 @@
+import { setupIDBShim } from "@/testing/IDBShim";
+import { initDB, loadSets, Database } from "@/mlpccg";
+import { PackBuilder, spanByRarity } from "@/mlpccg/draft";
+
+setupIDBShim();
+
+describe("mlpccg/draft", () => {
+  beforeAll(async () => {
+    jest.setTimeout(15000);
+    initDB();
+    await loadSets();
+  });
+
+  test("Set booster packs are generated correctly", async () => {
+    expect(Database).toBeTruthy();
+    const builder = await PackBuilder.fromSet("FF");
+    const pack = builder.buildPack();
+    // Check pack size
+    expect(pack).toHaveLength(12);
+    const rarities = spanByRarity(pack);
+    // Check pack distribution
+    expect(rarities["R"]).toHaveLength(1);
+    expect(rarities["U"]).toHaveLength(3);
+  });
+});