Scotland | ITP JAN-2026 | Tuan Nguyen | Sprint 3 | 2- Practice-tdd

Sprint-3/2-practice-tdd/count.js

@@ -1,5 +1,33 @@
-function countChar(stringOfCharacters, findCharacter) {
-  return 5
+function countChar(fullString,findCharacters) {
+  let count = 0;
+  // both of these if statement is for input validation if the input not a string.
+  if( typeof findCharacters !== "string" || typeof fullString !== "string"){
+    throw new Error("Invalid input");
+  };
+
+  if (findCharacters.length !== 1) {
+    throw new Error("findCharacters must be a single character");
+  }
+
+  for (let i = 0; i < fullString.length; i++){
+    if(fullString[i] === findCharacters){
+      count++;
+    }
+  }
+  return count;
 }
 
 module.exports = countChar;
+
+
+function assertTest(testInput,testCheck){
+ console.assert(
+  testInput === testCheck,
+  `Expect ${testInput} equal to ${testCheck}`
+ );
+};
+
+assertTest(countChar("whale fat hat cat","a"),4)
+assertTest(countChar("I need to lean more and know more","e"),5)
+assertTest(countChar("the city centre currently have a carnival","c"),4)
+assertTest(countChar("the cruise ship in in transit to south America","s"),4)

Sprint-3/2-practice-tdd/count.test.js

@@ -22,3 +22,24 @@ test("should count multiple occurrences of a character", () => {
 // And a character `char` that does not exist within `str`.
 // When the function is called with these inputs,
 // Then it should return 0, indicating that no occurrences of `char` were found.
+test( "should return count of zero occurrences of a character", () =>{
+   expect(countChar("go home and study","c")).toEqual(0);
+});
+
+// Scenario: Case-sensitive matching
+// Given a string containing both uppercase and lowercase versions of a letter,
+// When the function is called with a lowercase character,
+// Then it should only count the lowercase occurrences.
+
+test("should treat character matching as case-sensitive", () => {
+ expect(countChar("AaAa","A")).toEqual(2);
+});
+
+// Scenario: Non-alphabet characters
+// Given a string containing digits and symbols,
+// When the function is called with a non-alphabet character,
+// Then it should correctly count occurrences of that character.
+
+test("should count occurrences of non-alphabet characters", () => {
+  expect(countChar("1-2-3-1-1","1")).toEqual(3);
+});

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

@@ -1,5 +1,51 @@
 function getOrdinalNumber(num) {
-  return "1st";
+  // This is for num argument validation that go inside the function.
+  if ( !Number.isInteger(num)) {
+    throw new Error("Invalid input: the value must be a number");
+  }
+
+  // This allow float number to be round into it nearest integer.
+  const mainReminder = num % 100;
+  const secondReminder = num % 10;
+
+  if (mainReminder === 11 || mainReminder === 12 || mainReminder === 13) {
+    return `${num}th`;
+  }
+  switch (true) {
+    case secondReminder === 1:
+      return `${num}st`;
+    case secondReminder === 2:
+      return `${num}nd`;
+    case secondReminder === 3:
+      return `${num}rd`;
+    default:
+      return `${num}th`;
+  }
 }
 
 module.exports = getOrdinalNumber;
+
+function testAssert(inputNumber, outputNUmber) {
+  console.assert(
+    inputNumber === outputNUmber,
+    `Test failed: expected ${outputNUmber}, but got ${inputNumber}`
+  );
+}
+//Basic test of first digit integer
+testAssert(getOrdinalNumber(1), "1st");
+testAssert(getOrdinalNumber(2), "2nd");
+testAssert(getOrdinalNumber(3), "3rd");
+testAssert(getOrdinalNumber(4), "4th");
+//Test for 11, 12 and 13
+testAssert(getOrdinalNumber(11), "11th");
+testAssert(getOrdinalNumber(12), "12th");
+testAssert(getOrdinalNumber(13), "13th");
+//Test for double digit number
+testAssert(getOrdinalNumber(21), "21st");
+testAssert(getOrdinalNumber(32), "32nd");
+testAssert(getOrdinalNumber(43), "43rd");
+//Normal number and float number test.
+testAssert(getOrdinalNumber(101), "101st");
+testAssert(getOrdinalNumber(202), "202nd");
+testAssert(() => getOrdinalNumber(1.2), "Invalid input");
+testAssert(() => getOrdinalNumber(10.51), "Invalid input");

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

@@ -18,3 +18,64 @@ test("should append 'st' for numbers ending with 1, except those ending with 11"
   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".
+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(142)).toEqual("142nd");
+});
+
+// Case 3: Numbers ending with 3 (but not 13)
+// When the number ends with 3, except those ending with 13,
+// Then the function should return a string by appending 'rd'.
+test("should append 'rd' for numbers ending with 3, except those ending with 13", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(33)).toEqual("33rd");
+  expect(getOrdinalNumber(153)).toEqual("153rd");
+});
+
+// Case 4: Special cases 11, 12, 13
+// When the number ends with 11, 12, or 13,
+// Then the function should always append "th".
+test("should append 'th' for special cases 11, 12, 13", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(12)).toEqual("12th");
+  expect(getOrdinalNumber(13)).toEqual("13th");
+  expect(getOrdinalNumber(111)).toEqual("111th");
+  expect(getOrdinalNumber(212)).toEqual("212th");
+});
+
+// Case 5: All other numbers that is not end in 1,2 or 3.
+// When the number does not end with 1, 2, or 3,
+// Then the function should append "th".
+test("should append 'th' for all number that don't end in 1,2 or 3", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+  expect(getOrdinalNumber(100)).toEqual("100th");
+  expect(getOrdinalNumber(204)).toEqual("204th");
+});
+
+// Case 6: Float numbers should be giving a error since the function do nut accept float number input
+// When the input is a float,
+// Then the function should round it and return the correct ordinal.
+test("should return error for invalid input", () => {
+  expect(() => getOrdinalNumber(1.2)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(1.8)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(2.5)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(10.51)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(12.49)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(12.5)).toThrow("Invalid input");
+});
+
+// Case 7: Invalid inputs should throw an error
+// When the input is not a number,
+// Then the function should throw an error.
+test("should throw an error for invalid inputs", () => {
+  expect(() => getOrdinalNumber("10")).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(null)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(undefined)).toThrow("Invalid input");
+  expect(() => getOrdinalNumber(NaN)).toThrow("Invalid input");
+});