Implement repeatStr function and add comprehensive tests for various cases

Author: chefmatthaus-hub

practice-tdd/repeat-str.js

@@ -1,5 +1,12 @@
-export function repeatStr() {
-  // Your implementation of this function must *not* call String.prototype.repeat (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat).
-  // The goal is to re-implement that function, not to use it.
-  return "hellohellohello";
+export function repeatStr(str, count) {
+  let result = "";
+
+  for (let i = 0; i < count; i++) {
+    result = result + str;
+  }
+
+  if (count < 0) {
+    throw new Error("Count cannot be negative");
+  }
+    return result;  
 }

practice-tdd/repeat-str.test.js

@@ -16,10 +16,36 @@ test("should repeat the string count times", () => {
   expect(repeatedStr).toEqual("hellohellohello");
 });
 
+test("should return the original string when count is 1", () => {
+  const str = "hello";
+  const count = 1;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("hello");
+});
+
+test("should return an empty string", () => {
+  const str = "hello";
+  const count = 0;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
+
+test("should throw an error when count is negative", () => {
+  const str = "hello";
+  const count = -2;
+  expect(() => repeatStr(str, count)).toThrow();
+});
+
+test("should return Backstreet Boys lyrics", () => {
+  const str = "bye";
+  const count = 5;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("byebyebyebyebye");
+});
+
 // Case: handle count of 1:
 // Given a target string `str` and a `count` equal to 1,
 // When the repeatStr function is called with these inputs,
-// Then it should return the original `str` without repetition.
 
 // Case: Handle count of 0:
 // Given a target string `str` and a `count` equal to 0,