London| 26-ITP-Sep | Alan Mak | Sprint 2 | practice-tdd

practice-tdd/count.js

@@ -1,3 +1,5 @@
 export function countChar(stringOfCharacters, findCharacter) {
-  return 5
+  // Given a string `stringOfCharacters` and a single character `findCharacter` to search for,
+  const count = stringOfCharacters.split(findCharacter).length - 1;
+  return count
 }

practice-tdd/count.test.js

@@ -10,15 +10,71 @@ import { countChar } from "./count.js";
 // When the function is called with these inputs,
 // Then it should correctly count occurrences of `char`.
 
+// Case1: Multiple Occurrences in a string
 test("should count multiple occurrences of a character", () => {
   const str = "aaaaa";
   const char = "a";
   const count = countChar(str, char);
   expect(count).toEqual(5);
 });
 
+// Case2: Multiple Occurrences in a string with different characters
+test("should count multiple occurrences of a character in a string with different characters", () => {
+  const str = "abacadaeaf";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(5);
+});
+
+// Case3: Multiple Occurrences in different cases, case sensitive
+test("should count multiple occurrences of a character in different cases", () => {
+  const str = "AaAaAa";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(3);
+});
+
+// Scenario: Single Occurrence
+// Given the input string `str`,
+// And a character `char` that occurs exactly once in `str` (e.g., 'a' in 'abc'),
+// When the function is called with these inputs,
+// Then it should return 1, indicating a single occurrence of `char`.
+
+// Case4: Single Occurrence in a string with different characters
+test("should count a single occurrence of a character", () => {
+  const str = "abc";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(1);
+}); 
+
 // Scenario: No Occurrences
 // Given the input string `str`,
 // 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.
+
+//Case5: No Occurrences in a string with different characters
+test("should return 0 when character does not occur in the string", () => {
+  const str = "abc";
+  const char = "d";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});
+
+// Scenario: Edge Cases
+// Case6: Empty String
+test("should return 0 when the input string is empty", () => {
+  const str = "";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});
+
+// Case7: String contains spaces 
+test("should count occurrences of a character in a string with spaces", () => {
+  const str = "a b c a b c";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(2);
+});

practice-tdd/get-ordinal-number.js

@@ -1,3 +1,16 @@
 export function getOrdinalNumber(num) {
-  return "1st";
+  //Given a number `num`, the function should return a string representing the ordinal form of that number.
+  //When the number ends with 1, except those ending with 11,
+  //Then the function should return a string by appending "st" to the number.
+  if (num % 10 === 1 && num % 100 !== 11) return `${num}st`;
+
+  //When the number ends with 2, except those ending with 12,
+  //Then the function should return a string by appending "nd" to the number.
+  if (num % 10 === 2 && num % 100 !== 12) return `${num}nd`;
+
+  //When the number ends with 3, except those ending with 13,
+  //Then the function should return a string by appending "rd" to the number.
+  if (num % 10 === 3 && num % 100 !== 13) return `${num}rd`;
+
+  return `${num}th`;
 }

practice-tdd/get-ordinal-number.test.js

@@ -18,3 +18,49 @@ 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" 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");
+});
+
+// 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" to the number.
+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");
+});
+
+// Case 4: Numbers ending with 11, 12, or 13
+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");
+  expect(getOrdinalNumber(111)).toEqual("111th");
+  expect(getOrdinalNumber(112)).toEqual("112th");
+  expect(getOrdinalNumber(113)).toEqual("113th");
+});
+
+// Case 5: All other numbers
+test("should append 'th' for all other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(5)).toEqual("5th");
+  expect(getOrdinalNumber(6)).toEqual("6th");
+  expect(getOrdinalNumber(7)).toEqual("7th");
+  expect(getOrdinalNumber(8)).toEqual("8th");
+  expect(getOrdinalNumber(9)).toEqual("9th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+  expect(getOrdinalNumber(14)).toEqual("14th");
+  expect(getOrdinalNumber(15)).toEqual("15th");
+  expect(getOrdinalNumber(16)).toEqual("16th");
+  expect(getOrdinalNumber(17)).toEqual("17th");
+  expect(getOrdinalNumber(18)).toEqual("18th");
+  expect(getOrdinalNumber(19)).toEqual("19th");
+  expect(getOrdinalNumber(20)).toEqual("20th");
+});

practice-tdd/repeat-str.js

@@ -1,5 +1,20 @@
-export function repeatStr() {
+export function repeatStr(str, count) {
+  if (count < 0) {
+    throw new Error("Count must be a positive integer");
+  }
+  if (count === 0) {
+    return "";
+  }
+
   // Your implementation of this function must *not* call String.prototype.repeat (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat).
   // The goal is to re-implement that function, not to use it.
-  return "hellohellohello";
+  let result = "";
+  for (let i = 0; i < count; i++) { // i++ is i=i+1, i+=1, i=i+1, all are valid
+    result = result + str; //result += str; is also valid
+  }
+  return result;
+
+
 }
+
+

practice-tdd/repeat-str.test.js

@@ -20,13 +20,37 @@ test("should repeat the string count times", () => {
 // Given a target string `str` and a `count` equal to 1,
 // When the repeatStr function is called with these inputs,
 // Then it should return the original `str` without repetition.
+test("should return the original string when count is 1", () => {
+  const str = "hello";
+  const count = 1;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("hello");
+});
 
 // Case: Handle count of 0:
 // Given a target string `str` and a `count` equal to 0,
 // When the repeatStr function is called with these inputs,
 // Then it should return an empty string.
+test("should return an empty string when count is 0", () => {
+  const str = "hello";
+  const count = 0;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
 
 // Case: Handle negative count:
 // Given a target string `str` and a negative integer `count`,
 // When the repeatStr function is called with these inputs,
 // Then it should throw an error, as negative counts are not valid.
+test("should throw an error when count is negative", () => {
+  const str = "hello";
+  const count = -2;
+  expect(() => repeatStr(str, count)).toThrow(Error);
+});
+
+test ("should repeat the string count times", () => {
+  const str = "abc";
+  const count = 4;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("abcabcabcabc");
+});