Add category-based tests for ordinal number suffixes (st, nd, rd, th) including edge cases

Author: Pretty Taruvinga

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

@@ -1,9 +1,31 @@
 const getOrdinalNumber = require("./get-ordinal-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 (but not 12)
+// When the number ends with 2, except those ending with 12,
+// Then the function should return a string by appending "nd" to the number.
+test("should append 'nd' for numbers ending with 2, except those ending with 12", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+  expect(getOrdinalNumber(22)).toEqual("22nd");
+  expect(getOrdinalNumber(132)).toEqual("132nd");
+});
+
 // In this week's prep, we started implementing getOrdinalNumber.
+// This function takes a number as input and returns a string with the appropriate ordinal suffix ("st", "nd", "rd", "th").
+// For example:
+// - getOrdinalNumber(1) should return "1st"
 
 // Continue testing and implementing getOrdinalNumber for additional cases.
 // Write your tests using Jest — remember to run your tests often for continual feedback.
-
+test("should append 'rd' for numbers ending with 3, except those ending with 13", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(23)).toEqual("23rd");
+  expect(getOrdinalNumber(133)).toEqual("133rd");
+});
 // To ensure thorough testing, we need broad scenarios that cover all possible cases.
 // Listing individual values, however, can quickly lead to an unmanageable number of test cases.
 // Instead of writing tests for individual numbers, consider grouping all possible input values
@@ -13,8 +35,18 @@ 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");
+test("should append 'th' for numbers ending with 11, 12, or 13", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(12)).toEqual("12th");
+  expect(getOrdinalNumber(13)).toEqual("13th");
+});
+
+// Case 4: All other numbers
+// When the number does not end with 1, 2, or 3 (or ends with 11, 12, or 13),
+// Then the function should return a string by appending "th" to the number.
+test("should append 'th' for all other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+  expect(getOrdinalNumber(14)).toEqual("14th");
+  expect(getOrdinalNumber(100)).toEqual("100th");
 });