wrote function and tests for ordinal numbers

Author: mshayriyesaricicek

Sprint-3/2-practice-tdd/get-ordinal-number.js

@@ -1,5 +1,20 @@
 function getOrdinalNumber(num) {
-  return "1st";
+  // Check if input is a number
+  if (typeof num !== "number" || isNaN(num)) {
+    throw new Error("Input must be a valid number");
+  }
+
+  const j = num % 10; // checks what last number is
+  const k = num % 100; // checks what last two numbers are, needed to check for 11
+
+  if (k === 11 || k === 12 || k === 13) {
+    return num + "th";
+  }
+  if (j === 1) return num + "st";
+  if (j === 2) return num + "nd";
+  if (j === 3) return num + "rd";
+
+  return num + "th";
 }
 
 module.exports = getOrdinalNumber;

Sprint-3/2-practice-tdd/get-ordinal-number.test.js

@@ -13,8 +13,40 @@ const getOrdinalNumber = require("./get-ordinal-number");
 // Case 1: Numbers ending with 1 (but not 11)
 // When the number ends with 1, except those ending with 11,
 // Then the function should return a string by appending "st" to the number.
+
 test("should append 'st' for numbers ending with 1, except those ending with 11", () => {
   expect(getOrdinalNumber(1)).toEqual("1st");
   expect(getOrdinalNumber(21)).toEqual("21st");
   expect(getOrdinalNumber(131)).toEqual("131st");
 });
+
+// Case 2: Numbers ending with 2
+// When the number ends with 2,
+// Then the function should return a string by appending "nd" to the number.
+
+test("should append 'nd' for numbers ending with 2", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+  expect(getOrdinalNumber(32)).toEqual("32nd");
+  expect(getOrdinalNumber(252)).toEqual("252nd");
+});
+
+// Case 3: Numbers ending with 3
+// When the number ends with 3,
+// Then the function should return a string by appending "rd" to the number.
+
+test("should append 'rd' for numbers ending with 3", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(33)).toEqual("33rd");
+  expect(getOrdinalNumber(133)).toEqual("133rd");
+});
+
+// Case 4: The remaining numbers
+// When the number ends with 1, except those ending with 11
+// For all other numbers
+// Then the function should return a string by appending "th" to the number.
+
+test("should append 'th' for remaining numbers", () => {
+  expect(getOrdinalNumber(20)).toEqual("20th");
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(99)).toEqual("99th");
+});