Complete Sprint 3 practice TDD tasks

Author: mahmoudshaabo1984

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

@@ -1,5 +1,26 @@
+/**
+ * TDD Practice: Count Characters
+ * -----------------------------
+ * Goal: Implement a function that counts how many times a character appears in a string.
+ * This version uses a classic 'for...of' loop for maximum clarity.
+ */
+
 function countChar(stringOfCharacters, findCharacter) {
-  return 5
+  // 1. Initialize a counter starting from 0
+  let totalCount = 0;
+
+  // 2. Loop through every character in the input string
+  for (let currentCharacter of stringOfCharacters) {
+    // 3. Check if the current character matches the character we are looking for
+    if (currentCharacter === findCharacter) {
+      // 4. If they match, increment the counter by 1
+      totalCount++;
+    }
+  }
+
+  // 5. Return the final count after finishing the loop
+  return totalCount;
 }
 
+// Exporting the function so the test file can access it
 module.exports = countChar;

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

@@ -1,5 +1,32 @@
+/**
+ * getOrdinalNumber - Final Implementation
+ * --------------------------------------
+ * Converts a number to its English ordinal string (1st, 2nd, 3rd, etc.)
+ */
+
 function getOrdinalNumber(num) {
-  return "1st";
+  // 1. التعامل مع الاستثناءات (11, 12, 13)
+  // نستخدم % 100 للحصول على آخر رقمين
+  const lastTwoDigits = num % 100;
+  if (lastTwoDigits >= 11 && lastTwoDigits <= 13) {
+    return num + "th";
+  }
+
+  // 2. الحصول على آخر رقم في العدد
+  const lastDigit = num % 10;
+
+  // 3. تحديد النهاية بناءً على آخر رقم
+  switch (lastDigit) {
+    case 1:
+      return num + "st";
+    case 2:
+      return num + "nd";
+    case 3:
+      return num + "rd";
+    default:
+      return num + "th";
+  }
 }
 
+// تصدير الدالة للاختبار
 module.exports = getOrdinalNumber;

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

@@ -1,20 +1,37 @@
-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.
+/**
+ * getOrdinalNumber - Full Test Suite
+ */
 
-// 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
-// into meaningful categories. Then, select representative samples from each category to test.
-// This approach improves coverage and makes our tests easier to maintain.
+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", () => {
+test("should append 'st' for numbers ending with 1", () => {
   expect(getOrdinalNumber(1)).toEqual("1st");
   expect(getOrdinalNumber(21)).toEqual("21st");
-  expect(getOrdinalNumber(131)).toEqual("131st");
+  expect(getOrdinalNumber(101)).toEqual("101st");
+});
+
+// Case 2: Numbers ending with 2 (but not 12)
+test("should append 'nd' for numbers ending with 2", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+  expect(getOrdinalNumber(42)).toEqual("42nd");
+});
+
+// Case 3: Numbers ending with 3 (but not 13)
+test("should append 'rd' for numbers ending with 3", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(33)).toEqual("33rd");
+});
+
+// Case 4: The 'Teens' exceptions (11, 12, 13)
+test("should append 'th' for 11, 12, and 13", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(12)).toEqual("12th");
+  expect(getOrdinalNumber(13)).toEqual("13th");
+});
+
+// Case 5: General 'th' cases
+test("should append 'th' for other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
 });

Sprint-3/2-practice-tdd/repeat-str.js

@@ -1,5 +1,28 @@
-function repeatStr() {
-  return "hellohellohello";
+/**
+ * repeatStr - Final Logic Implementation
+ * -------------------------------------
+ * This function handles all TDD cases:
+ * 1. Multiple repetitions.
+ * 2. Count of 1 (Returns original string).
+ * 3. Count of 0 (Returns empty string).
+ * 4. Negative count (Throws an Error).
+ */
+
+function repeatStr(str, count) {
+  // 1. شرط الحماية (Guard Clause):
+  // نتحقق أولاً إذا كان الرقم سالباً قبل البدء بأي عملية.
+  if (count < 0) {
+    // إلقاء خطأ برمجي لإعلام نظام الاختبار أن المدخلات غير صحيحة
+    throw new Error("Count must be a non-negative integer");
+  }
+
+  // 2. استخدام دالة التكرار الجاهزة (repeat):
+  // هذه الدالة ذكية جداً؛ فهي تكرر النص (str) بعدد مرات (count).
+  // - إذا كان count يساوي 0، ستعيد نصاً فارغاً "" تلقائياً.
+  // - إذا كان count يساوي 1، ستعيد النص كما هو.
+  // - إذا كان count أكبر من 1، ستكرر النص.
+  return str.repeat(count);
 }
 
+// تصدير الدالة لكي يتمكن ملف الأختبار من الوصول إليها
 module.exports = repeatStr;

Sprint-3/2-practice-tdd/repeat-str.test.js

@@ -1,32 +1,46 @@
-// Implement a function repeatStr
-const repeatStr = require("./repeat-str");
-// Given a target string `str` and a positive integer `count`,
-// When the repeatStr function is called with these inputs,
-// Then it should:
+/**
+ * repeatStr - Full Test Suite
+ * --------------------------
+ * These tests cover all the cases required by the assignment:
+ * 1. Multiple repetitions.
+ * 2. Count of 1.
+ * 3. Count of 0.
+ * 4. Negative count (Error handling).
+ */
 
-// Case: handle multiple repetitions:
-// Given a target string `str` and a positive integer `count` greater than 1,
-// When the repeatStr function is called with these inputs,
-// Then it should return a string that contains the original `str` repeated `count` times.
+const repeatStr = require("./repeat-str");
 
-test("should repeat the string count times", () => {
+// Case 1: Handle multiple repetitions
+test("should repeat the string count times (e.g., 3 times)", () => {
   const str = "hello";
   const count = 3;
-  const repeatedStr = repeatStr(str, count);
-  expect(repeatedStr).toEqual("hellohellohello");
+  const result = repeatStr(str, count);
+  expect(result).toEqual("hellohellohello");
 });
 
-// Case: handle count of 1:
-// 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.
+// Case 2: Handle count of 1
+test("should return the original string without repetition when count is 1", () => {
+  const str = "hello";
+  const count = 1;
+  const result = repeatStr(str, count);
+  expect(result).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.
+// Case 3: Handle count of 0
+test("should return an empty string when count is 0", () => {
+  const str = "hello";
+  const count = 0;
+  const result = repeatStr(str, count);
+  expect(result).toEqual("");
+});
+
+// Case 4: Handle negative count
+test("should throw an error when count is a negative integer", () => {
+  const str = "hello";
+  const count = -1;
 
-// 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.
+  // Note: To test for errors in Jest, we wrap the function call in an anonymous function
+  expect(() => {
+    repeatStr(str, count);
+  }).toThrow();
+});