Implement repeatStr function to repeat a string a specified number of times with error handling for negative counts

Author: ashaahmed7

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

@@ -1,5 +1,6 @@
-function repeatStr() {
-  return "hellohellohello";
+function repeatStr(str, count) {
+  if (count < 0) throw new Error("Count cannot be negative");
+  return str.repeat(count);
 }
 
 module.exports = repeatStr;