Manchester | 26-ITP-Sept | Rahana Suleiman | Sprint 2 | Practice TDD

practice-tdd/count.js

@@ -1,3 +1,8 @@
 export function countChar(stringOfCharacters, findCharacter) {
-  return 5
+  let count = 0;
+  for (const char of stringOfCharacters) {
+  if (char === findCharacter) 
+    count ++
+  }
+  return count;
 }

practice-tdd/count.test.js

@@ -1,5 +1,5 @@
-// 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:
@@ -9,7 +9,6 @@ import { countChar } from "./count.js";
 // And a character `char` that occurs one or more times in `str` (e.g., 'a' in 'aaaaa'),
 // When the function is called with these inputs,
 // Then it should correctly count occurrences of `char`.
-
 test("should count multiple occurrences of a character", () => {
   const str = "aaaaa";
   const char = "a";
@@ -22,3 +21,9 @@ 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 0 when the character is not found in the string", () => {
+  const str = "hello";
+  const char = "z";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});

practice-tdd/get-ordinal-number.js

@@ -1,3 +1,18 @@
 export function getOrdinalNumber(num) {
-  return "1st";
+  const lastTwoDigits = num % 100;
+  const lastDigit = num % 10;
+  if (lastTwoDigits >= 11 && lastTwoDigits <= 13) {
+    return `${num}th`;
+  }
+  if (lastDigit === 1) {
+    return `${num}st`;
+  }
+  if (lastDigit === 2) {
+    return `${num}nd`;
+  }
+  if (lastDigit === 3) {
+    return `${num}rd`;
+  }
+
+  return `${num}th`;
 }

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

@@ -1,20 +1,39 @@
 import { getOrdinalNumber } from "./get-ordinal-number.js";
-// 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.
-
-// 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.
-
-// 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.
+// Case 1: Numbers ending with 1 (except 11)
 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 (except 12)
+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(102)).toEqual("102nd");
+});
+
+// Case 3: Numbers ending with 3 (except 13)
+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(103)).toEqual("103rd");
+});
+
+// Case 4: Teen numbers (11, 12, 13) and numbers ending in them
+test("should append 'th' for teen numbers 11, 12, 13 and their multiples", () => {
+  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 digits (0, 4, 5, 6, 7, 8, 9)
+test("should append 'th' for all other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+  expect(getOrdinalNumber(105)).toEqual("105th");
+});

practice-tdd/repeat-str.js

@@ -1,5 +1,13 @@
-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 RangeError("Count must be a non-negative integer");
+  }
+  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 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 = -1;
+  expect(() => repeatStr(str, count)).toThrow();
+});