updated tally for edge case toString

Author: Alex Jamshidi

Sprint-2/implement/tally.js

@@ -2,13 +2,13 @@ function tally(array) {
   if (!Array.isArray(array)) {
     throw new Error("Invalid array");
   }
-  tally = {};
+  const count = Object.create(null);
   array.forEach((item) => {
-    if (item in tally) {
-      tally[item] += 1;
-    } else tally[item] = 1;
+    if (item in count) {
+      count[item] += 1;
+    } else count[item] = 1;
   });
-  return tally;
+  return count;
 }
 
 module.exports = tally;

Sprint-2/implement/tally.test.js

@@ -33,8 +33,8 @@ describe("tally", () => {
   // When passed to tally
   // Then it should return counts for each unique item
   it("tally returns counts for each unique item", () => {
-    const array = ["a", "a", "b", "c"];
-    expect(tally(array)).toEqual({ a: 2, b: 1, c: 1 });
+    expect(tally(["a", "a", "b", "c"])).toEqual({ a: 2, b: 1, c: 1 });
+    expect(tally(["toString", "toString"])).toEqual({ toString: 2 });
   });
 
   // Given an invalid input like a string