Implement repeat-str and add Jest tests

Author: SandzSoft

Sprint-3/2-practice-tdd/repeat-str.js

@@ -1,7 +1,13 @@
-function repeatStr() {
+function repeatStr(str, count) {
   // 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";
+  let combinedStr = "";
+  if (count < 0) throw new Error("Invalid Count");
+
+  for (let i = 0; i < count; i++) {
+    combinedStr += str;
+  }
+  return combinedStr;
 }
 
 module.exports = repeatStr;

Sprint-3/2-practice-tdd/repeat-str.test.js

@@ -9,11 +9,26 @@ const repeatStr = require("./repeat-str");
 // When the repeatStr function is called with these inputs,
 // Then it should return a string that contains the original `str` repeated `count` times.
 
-test("should repeat the string count times", () => {
-  const str = "hello";
-  const count = 3;
-  const repeatedStr = repeatStr(str, count);
-  expect(repeatedStr).toEqual("hellohellohello");
+describe("repeatStr", () => {
+  test("repeats string count times when count is greater than 1", () => {
+    expect(repeatStr("hello", 3)).toEqual("hellohellohello");
+  });
+
+  test("returns original string when count is 1", () => {
+    expect(repeatStr("hello", 1)).toEqual("hello");
+  });
+
+  test("returns empty string when count is 0", () => {
+    expect(repeatStr("hello", 0)).toEqual("");
+  });
+
+  test("throws an error when count is negative", () => {
+    expect(() => repeatStr("hello", -3)).toThrow("Invalid Count");
+  });
+
+  test("returns empty string when the input string is empty", () => {
+    expect(repeatStr("", 3)).toEqual("");
+  });
 });
 
 // Case: handle count of 1: