hand#split

src/hand.js

@@ -0,0 +1,37 @@
+export default class Hand {
+  constructor({ type }) {
+    this.type = type;
+    this.cards = [];
+  }
+
+  isDealer() {
+    return this.type === "dealer";
+  }
+
+  isPlayer() {
+    return this.type === "player";
+  }
+
+  take(card) {
+    this.cards.push(card);
+  }
+
+  split() {
+    if (
+      !(
+        this.type === "player" &&
+        this.cards.length === 2 &&
+        this.cards[0].name === this.cards[1].name
+      )
+    ) {
+      throw new Error("failed to split");
+    }
+
+    const popped = this.cards.pop();
+
+    const splitted = new Hand({ type: "player" });
+    splitted.take(popped);
+
+    return splitted;
+  }
+}

test/src/hand.test.js

@@ -0,0 +1,32 @@
+import { expect } from "chai";
+import Hand from "./../../src/hand";
+import Card from "./../../src/card";
+
+describe("Hand", () => {
+  describe("#split", () => {
+    const hand = new Hand({ type: "player" });
+
+    it("success with a pair", () => {
+      const card1 = new Card({ suite: "hearts", name: "10" });
+      const card2 = new Card({ suite: "diamonds", name: "10" });
+
+      hand.take(card1);
+      hand.take(card2);
+
+      const splitted = hand.split();
+
+      expect(hand.cards.length).to.eql(1);
+      expect(splitted.cards.length).to.eql(1);
+    });
+
+    it("fail with a non-pair", () => {
+      const card1 = new Card({ suite: "hearts", name: "10" });
+      const card2 = new Card({ suite: "diamonds", name: "9" });
+
+      hand.take(card1);
+      hand.take(card2);
+
+      expect(() => hand.split()).to.throw("failed to split");
+    });
+  });
+});