London | 26-ITP-SEPT | Carol Nassuna | Sprint 2 | Practice TDD

practice-tdd/count.js

@@ -1,3 +1,11 @@
 export function countChar(stringOfCharacters, findCharacter) {
-  return 5
+  let count = 0;
+
+  for (let i = 0; i < stringOfCharacters.length; i++) {
+    if (stringOfCharacters[i] === findCharacter) {
+      count++;
+    }
+  }
+
+  return count;
 }

practice-tdd/count.test.js

@@ -1,5 +1,6 @@
 // implement a function countChar that counts the number of times a character occurs in a string
 import { countChar } from "./count.js";
+
 // Given a string `str` and a single character `char` to search for,
 // When the countChar function is called with these inputs,
 // Then it should:
@@ -22,3 +23,17 @@ 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 count multiple occurrences of a character", () => {
+  const str = "aaaaa";
+  const char = "z";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});
+
+test("should count multiple occurrences of a character", () => {
+  const str = "aaaaa";
+  const char = "7";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});

practice-tdd/get-ordinal-number.js

@@ -1,3 +1,14 @@
 export function getOrdinalNumber(num) {
-  return "1st";
+  const lastTwoDigits = num % 100;
+
+  if (lastTwoDigits >= 11 && lastTwoDigits <= 13) {
+    return `${num}th`;
+  }
+
+  const lastDigit = num % 10;
+  if (lastDigit === 1) return `${num}st`;
+  if (lastDigit === 2) return `${num}nd`;
+  if (lastDigit === 3) return `${num}rd`;
+
+  return `${num}th`;
 }

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

@@ -18,3 +18,21 @@ test("should append 'st' for numbers ending with 1, except those ending with 11"
   expect(getOrdinalNumber(21)).toEqual("21st");
   expect(getOrdinalNumber(131)).toEqual("131st");
 });
+
+test("should append 'nd' for numbers ending with 2", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+  expect(getOrdinalNumber(22)).toEqual("22nd");
+  expect(getOrdinalNumber(122)).toEqual("122nd");
+});
+
+test("should append 'rd' for numbers ending with 3", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(23)).toEqual("23rd");
+  expect(getOrdinalNumber(123)).toEqual("123rd");
+});
+
+test("should append 'th' for numbers ending with 4, except those ending with 0", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(144)).toEqual("144th");
+  expect(getOrdinalNumber(40)).toEqual("40th");
+});

practice-tdd/repeat-str.js

@@ -1,5 +1,14 @@
-export function repeatStr() {
+export function repeatStr(str, count) {
   // 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";
+
+  if (count < 0) {
+    throw new Error("negative counts are not valid");
+  }
+  let result = "";
+
+  for (let i = 0; i < count; i++) {
+    result += str;
+  }
+  return result;
 }

practice-tdd/repeat-str.test.js

@@ -21,12 +21,32 @@ test("should repeat the string count times", () => {
 // When the repeatStr function is called with these inputs,
 // Then it should return the original `str` without repetition.
 
+test("should repeat the string count times", () => {
+  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 repeat the string count times", () => {
+  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, as negative counts are not valid", () => {
+  const str = "hello";
+  const count = -1;
+  expect(() => repeatStr(str, count)).toThrow("negative counts are not valid");
+});