feat(sprint-3): implement getOrdinalNumber function with TDD

Author: Tarawally

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

@@ -1,5 +1,14 @@
 function getOrdinalNumber(num) {
-  return "1st";
+  const lastDigit = num % 10;
+  const lastTwoDigits = num % 100;
+
+  if (lastTwoDigits === 11 || lastTwoDigits === 12 || lastTwoDigits === 13) {
+    return `${num}th`;
+  }
+  if (lastDigit === 1) return `${num}st`;
+  if (lastDigit === 2) return `${num}nd`;
+  if (lastDigit === 3) return `${num}rd`;
+  return `${num}th`;
 }
 
 module.exports = getOrdinalNumber;

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

@@ -1,13 +1,61 @@
 const getOrdinalNumber = require("./get-ordinal-number");
-// In this week's prep, we started implementing getOrdinalNumber
-
-// continue testing and implementing getOrdinalNumber for additional cases
-// Write your tests using Jest - remember to run your tests often for continual feedback
-
-// Case 1: Identify the ordinal number for 1
-// When the number is 1,
-// Then the function should return "1st"
 
 test("should return '1st' for 1", () => {
   expect(getOrdinalNumber(1)).toEqual("1st");
 });
+
+test("should return '2nd' for 2", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+});
+
+test("should return '3rd' for 3", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+});
+
+test("should handle numbers ending in 1 (except 11)", () => {
+  expect(getOrdinalNumber(21)).toEqual("21st");
+  expect(getOrdinalNumber(31)).toEqual("31st");
+  expect(getOrdinalNumber(101)).toEqual("101st");
+});
+
+test("should handle numbers ending in 2 (except 12)", () => {
+  expect(getOrdinalNumber(22)).toEqual("22nd");
+  expect(getOrdinalNumber(42)).toEqual("42nd");
+});
+
+test("should handle numbers ending in 3 (except 13)", () => {
+  expect(getOrdinalNumber(23)).toEqual("23rd");
+  expect(getOrdinalNumber(33)).toEqual("33rd");
+});
+
+test("should handle special cases 11, 12, 13", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(12)).toEqual("12th");
+  expect(getOrdinalNumber(13)).toEqual("13th");
+});
+
+test("should handle numbers ending in 4-9, 0", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(5)).toEqual("5th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+});
+
+test("should return '100th' for 100", () => {
+  expect(getOrdinalNumber(100)).toEqual("100th");
+});
+
+test("should return '24th' for 24", () => {
+  expect(getOrdinalNumber(24)).toEqual("24th");
+});
+
+test("should return '111th' for 111", () => {
+  expect(getOrdinalNumber(111)).toEqual("111th");
+});
+
+test("should return '112th' for 112", () => {
+  expect(getOrdinalNumber(112)).toEqual("112th");
+});
+
+test("should return '113th' for 113", () => {
+  expect(getOrdinalNumber(113)).toEqual("113th");
+});