Check valid card ranks

Author: russom-g

implement-and-rewrite-tests/implement-tests-with-node-test/3-get-card-value.test.js

@@ -8,9 +8,7 @@ import { getCardValue } from "../implement/3-get-card-value.js";
 test("Valid single-digit card", () => {
   assert.equal(getCardValue("9♠"), 9);
 });
-
 test("Arbitrary non-card string", () => {
   assert.throws(() => getCardValue("invalid"), /Expected a number followed by a suit, but got "invalid"/, "Expected clear error");
 });
-
 // TODO: What other invalid card cases can you think of?

implement-and-rewrite-tests/implement/3-get-card-value.js

@@ -25,11 +25,20 @@
 
 export function getCardValue(card) {
   // TODO: Implement this function
-  if (card === "A") {
+  if (typeof card !== "string") {
+    throw new Error("Invalid");
+  }
+  const rank = card.slice(0, -1);
+
+  if (rank === "A") {
     return 11;
-  } else if (card === "J" || card === "Q" || card === "K") {
+  }
+  if (rank === "J" || rank === "Q" || rank === "K") {
     return 10;
-  } else {
-    return Number(card);
   }
+  const value = Number(rank);
+  if (Number.isInteger(value) && value >= 2 && value <= 10) {
+    return value;
+  }
+  throw new Error(`Expected a number followed by a suit, but got "${card}"`);
 }