Cape Town | 26-ITP-Sep | Quentin Gwele | Sprint 2 | coursework/practice-TDD

practice-tdd/count.js

@@ -1,3 +1,9 @@
 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

@@ -22,3 +22,37 @@ 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 does not occur in the string", () => {
+  const str = "hello";
+  const char = "z";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});
+
+test("should count correctly when the character appears in only part of the string", () => {
+  const str = "hello";
+  const char = "l";
+  const count = countChar(str, char);
+  expect(count).toEqual(2);
+});
+
+test("should count a character that appears once in the middle of the string", () => {
+  const str = "abc";
+  const char = "b";
+  const count = countChar(str, char);
+  expect(count).toEqual(1);
+});
+
+test("should count a character that appears in separate parts of the string", () => {
+  const str = "banana";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(3);
+});
+
+test("should return 0 when the string is empty", () => {
+  const str = "";
+  const char = "a";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});

practice-tdd/get-ordinal-number.js

@@ -1,3 +1,12 @@
 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 +18,33 @@ 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)
+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)
+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");
+});
+
+// Case 5: All other numbers
+test("should append 'th' for all other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(10)).toEqual("10th");
+  expect(getOrdinalNumber(25)).toEqual("25th");
+  expect(getOrdinalNumber(100)).toEqual("100th");
+});

practice-tdd/repeat-str.js

@@ -1,5 +1,11 @@
-export function repeatStr() {
-  // 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";
-}
+export function repeatStr(str, count) {
+  if (count < 0) {
+    throw new Error("Invalid count: count must not be negative");
+  }
+
+  let result = "";
+  for (let i = 0; i < count; i++) {
+    result += str;
+  }
+  return result;
+}

practice-tdd/repeat-str.test.js

@@ -20,13 +20,55 @@ 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 = -1;
+  expect(() => repeatStr(str, count)).toThrow();
+});
+
+test("should return an empty string when repeating an empty string several times", () => {
+  const str = "";
+  const count = 3;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
+
+test("should return an empty string when repeating an empty string once", () => {
+  const str = "";
+  const count = 1;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
+
+test("should return an empty string when repeating an empty string zero times", () => {
+  const str = "";
+  const count = 0;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
+
+test("should throw an error when count is negative, even for an empty string", () => {
+  const str = "";
+  const count = -1;
+  expect(() => repeatStr(str, count)).toThrow();
+});